• TABLE OF CONTENTS
HIDE
 Title Page
 The authors
 Table of Contents
 Construction of a still air...
 Parts of an egg
 Incubating and hatching eggs
 Care of chicks after hatching
 Displaying living chicken...
 The preparation and preservation...
 Landmarks of embryonic develop...
 Preparations/demonstration of various...
 Reference






Group Title: Florida Cooperative Extension Service circular 813
Title: Incubation, embryonic development, embryo and organ display, and baby chick care
CITATION PAGE IMAGE ZOOMABLE PAGE TEXT
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00014502/00001
 Material Information
Title: Incubation, embryonic development, embryo and organ display, and baby chick care
Series Title: Circular
Physical Description: 16 p. : ill. ; 28 cm.
Language: English
Creator: Wilson, Henry R ( Henry Russell )
Florida Cooperative Extension Service
Publisher: University of Florida, Cooperative Extension Service, Institute of Food and Agricultural Sciences
Place of Publication: Gainesville Fla.
Publication Date: [1996]
 Subjects
Subject: Chickens -- Embryos   ( lcsh )
Eggs -- Incubation   ( lcsh )
Chicks   ( lcsh )
Poultry -- Hatcheries   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
bibliography   ( marcgt )
non-fiction   ( marcgt )
 Notes
Bibliography: Includes bibliographical references.
Statement of Responsibility: H. R. Wilson ... et al.
General Note: Cover title.
General Note: "Revised September 1996"--P. 4 of cover.
Funding: Circular (Florida Cooperative Extension Service) ;
 Record Information
Bibliographic ID: UF00014502
Volume ID: VID00001
Source Institution: Marston Science Library, George A. Smathers Libraries, University of Florida
Holding Location: Florida Agricultural Experiment Station, Florida Cooperative Extension Service, Florida Department of Agriculture and Consumer Services, and the Engineering and Industrial Experiment Station; Institute for Food and Agricultural Services (IFAS), University of Florida
Rights Management: All rights reserved, Board of Trustees of the University of Florida
Resource Identifier: aleph - 002120100
oclc - 35757606
notis - AKV9849

Table of Contents
    Title Page
        Title Page
    The authors
        Unnumbered ( 2 )
    Table of Contents
        Table of Contents
    Construction of a still air incubator
        Page 1
        Materials and supplies
            Page 1
        Construction
            Page 2
            Page 3
    Parts of an egg
        Page 4
    Incubating and hatching eggs
        Page 5
        Fertile eggs
            Page 5
        Temperature
            Page 5
        Humidity
            Page 5
        Positions of eggs
            Page 6
        Ventilation
            Page 7
        Candling incubated eggs
            Page 7
    Care of chicks after hatching
        Page 8
        Brooder house
            Page 8
        Litter
            Page 8
        Brooder
            Page 8
        Chick guard
            Page 8
        Feeding
            Page 9
        Watering
            Page 9
        Some helpful hints
            Page 9
        Layer house
            Page 10
    Displaying living chicken embryos
        Page 10
        Materials ans supplies
            Page 10
        Procedures
            Page 10
    The preparation and preservation of embryos
        Page 11
        Materials and supplies
            Page 11
        Procedures
            Page 11
    Landmarks of embryonic development
        Page 12
        Before the egg is laid (pre-oviposition)
            Page 12
        During incubation
            Page 12
            Page 13
            Page 14
    Preparations/demonstration of various anatomical systems of the fowl
        Page 15
        Preparation of a skeleton for exhibition
            Page 15
        Staining tissue of intact embryonic specimens
            Page 15
        Preparation of soft organs for exhibition
            Page 15
            Page 16
    Reference
        Page 17
Full Text

Circular 813


(3~
'Rc~ .Y)67


INCUBATION,
EMBRYONIC DEVELOPMENT,
EMBRYO AND ORGAN DISPLAY,
AND BABY CHICK CARE


H.R. WILSON, F.B. MATHER, R.A. BUCKLIN, AND J.P. JACOB


i UNIVERSITY OF
FLORIDA
Cooperative Extension Service
Institute of Food and Agricultural Sciences









1o1


<13

\9VW

,. Dairy and Poultry Sciences Department
iaw P.O. Box 110920
University of Florida
Gainesville, Florida 32611-0920
(352) 392-5594
FAX (352) 392-5595

and

Agricultural and Biological Engineering
P.O. Box 110570
University of Florida
Gainesville, Florida 32611-0570
(352) 392-7728
FAX (352) 392-4092
















AUTHORS

Dr. H.R. Wilson is a professor, Dr. F.B. Mather is an associate professor, and Dr. J.P. Jacob is Extension
Coordinator in the Dairy and Poultry Sciences Department;
Dr. R.A. Bucklin is a professor in the Agricultural and Biological Engineering Department, IFAS, University
of Florida, Gainesville, Florida.

ACKNOWLEDGEMENT
The authors wish to thank Dr. Ray Bucklin, Department of Agricultural Engineering, for technical assistance
in providing diagrams of incubator and chandler.








TABLE OF CONTENTS


Introduction

Construction of a Still-Air Incubator ..... . . .......... ........... 1.
M materials and Supplies ....................... ............... ... 1.
C construction . . . . . . . .. . . . .2.

Parts of an Egg ..... ................. ........ .......... ...... 4.

Incubating and Hatching Eggs ...................... ................ 5.
Fertile Eggs . . . . .. . . . . . ... 5.
Temperature ...... ...... .. ........ ............... ...5.
Humidity... . . ...... ........... ... .......... .... 5.
Position of Eggs. . . . ........... . **................. 6.
Ventilation . . . . . . . . 7.
Candling Incubated Eggs . . . . . . . * * 7.

Incubation Time, Temperature, and Humidity Required for Various Species (Table 1). 6.

Care of Chicks after Hatching . . .. . .... ......... 8.
Brooder House . .. . . . ..... ............ ....... 8.
Litter ........ . . . .. ........... . .......... ..... 8.
Brooder ... . . . . . . . . . . . 8.
Chick Guard . . .. . . . . . . . 8.
Feeding . . . . . . . . . . . 9.
W watering ..... ... ....... ..... .... ....... ... ....... ...... 9.
Som e Helpful H ints ..... . . . . . . . . 9.
Layer House ........ .. ...... ........ .. ............... .... 10.

Displaying Living Chicken Embryos .......... ............... ... .......10.
Materials and Supplies . . ... ..........................1 0.
Procedures . . . . . . . . . . . 10.

The Preparation and Preservation of Embryos . . .. ... . . 11.
M materials and Supplies . . . . . . . . . .... 11.
Procedures ...... ,. ............... ... ..... ................ 11.

Landmarks of Embryonic Development. ... . . . . .... .1 12.
Before the Egg is Laid iPre-Ovipositioni ................. ............. 12.
During Incubation ..... ............. .... .. ..... .......... 12.

Preparation/Demonstration of Various Anatomical Systems of the Fowl .. . ..15.
Preparation of a Skeleton for Exhibition . . . . . . ; 15.
Staining Tissue of Intact Embryonic Specimens . . ... . . . 15.
Preparation of Soft Organs for Exhibition . . . . .............15.

References and Suggested Readings . . . . . . . back cover






UNIVERSITY OF FLO)RiA LIBRARIES






C.1w3ar13


INTRODUCTION

The avian embryo is an excellent model for
teaching students about nature. The bird supplies a
conveniently packaged embryo which requires only
the addition of heat, moisture, air, and movement to
stimulate normal development and growth.
Nevertheless, the process ofincubation is complicated
because it involves the changing of raw chemical
materials found in the yolk, albumen, and shell into
a complete living chick. Amazingly, the process is
successful a high percentage of the time.

Artificial methods of incubation are utilized
naturally by several species of birds, including the
Megapodiidae family of Indonesia, New Guinea and
other nearby areas, the Mallee Fowl and Brush Turkey
ofAustralia, and several other species. Many ofthese
species use the heat of decomposing humus to warm
the eggs. Some of the early attempts by humans to
incubate chicken eggs also used decomposing humus,
in the form of dung heaps, to produce the heat of
incubation. This type of system was used in Egypt
and was mentioned in the writings of Aristotle (384-
322 BCi. A much more sophisticated system was
developed later in Egypt in which incubation chambers
were built of mud bricks with each chamber having a
capacity for hundreds of eggs. Straw, charcoal, and
dung were common heating fuels. Small mud or brick
ovens were reported to be in use in China by the Ch'in
Period (246-207 BC i.

In Europe, artificial incubation was mostly a
hobby or toy for royalty and the rich. An Egyptian
incubation system was introduced into Italy about
1200 AD. One of the first mechanically controlled
incubators was invented by Drebbel, a Dutch
mechanic, about 1633 AD. It was heated indirectly by
hot water and was controlled by a mercury-alcohol
thermostat. Unfortunately, the principle was not
applied until 200 years later. A bimetal thermostat
was invented in France by Bonnemain about 1783
and subsequently was used extensively in many types
of incubators.

During the early part of the twentieth century,
incubator capacity was 40 to 400 eggs and large-
capacity hatcheries placed these incubators in rows
and tiers. However, two important developments
changed this system. One was the construction of
large incubators 136,000 eggs) by Cyphers in 1907.


Another was the invention of a forced draft incubator
by Hastings in 1911. In 1923, Petersime combined
these advances with an all-electric system, thus
beginning the modern era of incubation.

CONSTRUCTION OF A
STILL-AIR INCUBATOR

An attractive, inexpensive incubator can be
constructed by using cardboard boxes as the basic
construction material. This design uses a light bulb as
a source of heat and a commercial thermostat to
regulate the temperature. As a source of moisture, a
cake pan filled with water works fine.

Materials and Supplies

All the dimensions mentioned below must be
adjusted to the size of the boxes used and are only
suggested sizes.

* 1 box 18" long x 14" wide x 13" high (corrugated
cardboard)
1 box 16" long x 12" wide x 12" high (corrugated
cardboard) (The larger box should be 2" greaterin
both length and width and 1" higher.)
1 sheet of glass 18" x 14" (size of larger box)
0.5" hardware cloth 20" x 16"(4" wider and longer
than smaller box)
Light socket (porcelain)
Electric cord, 7' to 20' in length
Male electric plug
Water pan (cake pan should cover at least halfaf
the bottom of smaller box)
Light bulb (60 75 watt)
1" masking tape (freezer tape)
Glue
Brads or small bolts
Insulating material (newspapers, whole or
shredded)
Screwdriver
Tin snips (wire cutters)
Pencil
Knife and/or scissors
Yardstick (ruler)
Block of wood 0.75" x 4" x 4"
Round rolled oats box or fruit juice can (this acts
as chimney around light)
Aluminum foil (to line inside of box)
Newspapers for bottom- should be several layers
Thermostat (wafer or solid state types)
Thermometer


Page 1






C.1w3ar13


INTRODUCTION

The avian embryo is an excellent model for
teaching students about nature. The bird supplies a
conveniently packaged embryo which requires only
the addition of heat, moisture, air, and movement to
stimulate normal development and growth.
Nevertheless, the process ofincubation is complicated
because it involves the changing of raw chemical
materials found in the yolk, albumen, and shell into
a complete living chick. Amazingly, the process is
successful a high percentage of the time.

Artificial methods of incubation are utilized
naturally by several species of birds, including the
Megapodiidae family of Indonesia, New Guinea and
other nearby areas, the Mallee Fowl and Brush Turkey
ofAustralia, and several other species. Many ofthese
species use the heat of decomposing humus to warm
the eggs. Some of the early attempts by humans to
incubate chicken eggs also used decomposing humus,
in the form of dung heaps, to produce the heat of
incubation. This type of system was used in Egypt
and was mentioned in the writings of Aristotle (384-
322 BCi. A much more sophisticated system was
developed later in Egypt in which incubation chambers
were built of mud bricks with each chamber having a
capacity for hundreds of eggs. Straw, charcoal, and
dung were common heating fuels. Small mud or brick
ovens were reported to be in use in China by the Ch'in
Period (246-207 BC i.

In Europe, artificial incubation was mostly a
hobby or toy for royalty and the rich. An Egyptian
incubation system was introduced into Italy about
1200 AD. One of the first mechanically controlled
incubators was invented by Drebbel, a Dutch
mechanic, about 1633 AD. It was heated indirectly by
hot water and was controlled by a mercury-alcohol
thermostat. Unfortunately, the principle was not
applied until 200 years later. A bimetal thermostat
was invented in France by Bonnemain about 1783
and subsequently was used extensively in many types
of incubators.

During the early part of the twentieth century,
incubator capacity was 40 to 400 eggs and large-
capacity hatcheries placed these incubators in rows
and tiers. However, two important developments
changed this system. One was the construction of
large incubators 136,000 eggs) by Cyphers in 1907.


Another was the invention of a forced draft incubator
by Hastings in 1911. In 1923, Petersime combined
these advances with an all-electric system, thus
beginning the modern era of incubation.

CONSTRUCTION OF A
STILL-AIR INCUBATOR

An attractive, inexpensive incubator can be
constructed by using cardboard boxes as the basic
construction material. This design uses a light bulb as
a source of heat and a commercial thermostat to
regulate the temperature. As a source of moisture, a
cake pan filled with water works fine.

Materials and Supplies

All the dimensions mentioned below must be
adjusted to the size of the boxes used and are only
suggested sizes.

* 1 box 18" long x 14" wide x 13" high (corrugated
cardboard)
1 box 16" long x 12" wide x 12" high (corrugated
cardboard) (The larger box should be 2" greaterin
both length and width and 1" higher.)
1 sheet of glass 18" x 14" (size of larger box)
0.5" hardware cloth 20" x 16"(4" wider and longer
than smaller box)
Light socket (porcelain)
Electric cord, 7' to 20' in length
Male electric plug
Water pan (cake pan should cover at least halfaf
the bottom of smaller box)
Light bulb (60 75 watt)
1" masking tape (freezer tape)
Glue
Brads or small bolts
Insulating material (newspapers, whole or
shredded)
Screwdriver
Tin snips (wire cutters)
Pencil
Knife and/or scissors
Yardstick (ruler)
Block of wood 0.75" x 4" x 4"
Round rolled oats box or fruit juice can (this acts
as chimney around light)
Aluminum foil (to line inside of box)
Newspapers for bottom- should be several layers
Thermostat (wafer or solid state types)
Thermometer


Page 1







Circular 813


Construction

Cut flaps from smallerbox and attach the thermostat
to one of the longer sides making sure that the wafer
clears the upper edge by at least 0.25". A portion of
one of the flaps can be glued to the bottom of this box
to fill in the space where the inner flaps do not
come together
THERMOSTAT
(Diagram A WAFER





A.




GLUED
FLAP



Apply glue on the inside of
the bottom around the center portion of the larger
box. Now center the smaller box inside the larger box
and place a weight in the bottom to ensure bonding.
There should be at least 0.5" to 1" between the sides
of the inner and outer boxes. Make a hole through
both boxes for the rod that holds the wafer of the
thermostat ibe sure that the alignment is correct).
This may not be necessary for solid state thermostats.
Make another hole through both boxes 1" from the
bottom and centered so that the electric cord can pass
through it.

Lightly stuff the area between the boxes with
insulating material (newspapers are fine whole or
shredded in strips). Do not bulge sides (Diagram B).

LARGE BOX-- HOLES FOR
NWs- THEIR MSTAT ROD
SECOND (SMALL)
Box



SB.



HOLES
FOR ELECTRIC
CORD


Draw a line all the way around on the outside of
the larger box at the level of the upper edge of the
smaller box. With a knife or single edged razor blade,
cut along this line. Make sure the cut only goes
through the outer cardboard layer and nicks
the corrugated portion. It must not cut through
the inner layer of cardboard.

Make diagonal cuts in corners of the larger box so
the flaps will fold neatly (Diagram C).



C.




Fold the flaps inward along the cut portion.

Mark these flaps where they come in contact with
the inner edge of the smaller box and cut along these
lines (Diagram D).

Tape the flaps with 1" masking tape to the edge of
the smaller box. Cut a piece of hardware cloth
(0.5"mesh) so that it is 4" wider and 4" longer than the
inside diameter of the smaller box.

Using the tin snips, cut a 2" square from each
corner ofthe hardware cloth. Then bend the projecting
pieces of cloth so they form legs to support the screen.
It should fit snugly in the bottom ofthe box (Diagram E).

Cut 4 ventilation holes (1" in diameter) where
they will be level with the top of the eggs. Cut
ventilation hole covers that are 1.5" to 2" out of extra
cardboard to regulate air-flow and attach to the inner
box with brads or small bolts.

Wire the light socket so that electricity flows
through the thermostat (Diagram F). The light socket
should be attached to a wooden base (0.75" x 4" x 4"
block). Heating coils of various types may be
substituted for the light bulb as a heat source.

Line the box with aluminum foil, place several
layers of newspaper in the bottom, place cake pan
under screen, assemble thermostat on back wall,
insert light bulb and place rolled oats box or juice can
around light (Diagram G).


Page 2






Circar 813


F







Light Plu
Socket





G


VENTILATION
HOLES --h


Page 3






Circular 813


Regulate temperature so that it ranges between
1010 and 1030F (38.3 to 39.4C) approximately 2
inches above the screen (or top ofthe egg). Check unit
periodically for several hours to make sure it is
functioning properly before setting eggs.

Place eggs on hardware cloth around the light.
Cover the top of the box with the glass.

Small incubators may also be constructed from
styrofoam coolers. Ventilation holes, egg holding
screen, water pan, thermostats, heat source, etc. are
installed as with the cardboard structure.

To construct a more permanent type of incubator,
construct the box using 0.5-inch or 0.75-inch
waterproof or marine plywood. Protect the wood with
two or three coats of a polyurethane finish. This also
will permit easy cleaning and disinfection of the
incubator.

Small electric fans can be installed in incubators
to circulate the air and maintain a more uniform
temperature and humidity. Incubators with fans
should be operated at 99.50F (37.5C).

Small incubators also may be purchased from
several manufacturers and distributors. Automatic
egg turners also are available and can be adapted to
many small incubators.

PARTS OF AN EGG

The egg is composed of three major parts which
are the yolk, albumen, and shell with egg membranes
(Figure 1). The yolk color may vary from light to dark
Inne

Chalazit
al








./



FIGURE 1. Outer tl
alb
Structure of the fertile egg.


yellow depending upon the carotene pigment levels in
the feed. There may be alternating light and dark
rings within the yolk, indicating pigment blood levels
during yolk deposition. The yolk is enclosed in the
vitelline membrane, a non-cellular felting of protein
fibers. The embryo develops from the germinal disc,
or blastoderm, which appears as a white spot on the
yolk. It contains the genetic material from both
female and male parents. The yolk furnishes almost
half of the protein and all of the fat for embryo
nutrition. It also contains most of the vitamins and
minor minerals required by the embryo.

The albumen is composed of four layers: the
chalaziferous with chalazae which is composed of
mucin-like fibers twisted on to the yolk and anchored
in the surrounding albumen; the inner thin layer; the
thick layer; and the outer thin layer. The albumen
furnishes most of the water and slightly more than
half of the protein needed by the embryo.

The yolk and albumen are surrounded by two
membranes, the inner or egg membrane and outer or
shell membrane. The hard shell is deposited on the
outer surface of the shell membrane. The shell and
membranes are porous to allow the exchange ofoxygen,
carbon dioxide and water vapor. A space appears
between the egg and shell membranes in the large end
of the egg. This is the air cell. It functions as an air
reservoir for lung respiration by the embryo just prior
to hatching. The shell also contributes most of the
calcium needed by the embryo for bone formation.



Yolk vitelline
Germinal membrane
disc Latlbra

oen
Ought yOlk layer







membrane
Shell


Shell


Thickl
albumen


\Chalazae


Page 4


r thi
albun
Ibum
lbum






Circular 813


INCUBATING AND HATCHING EGGS

Fertile Eggs

A supply of fertile eggs may be obtained from
hatcheries or from any poultry flock where roosters
are being kept with the hens. Eggs purchased from
food stores are not fertile and therefore will not hatch.
Eggs that are cracked, abnormal, dirty or covered
with oils or other sealants should not be incubated. If
eggs are soiled, they may be dry cleaned with a clean
paper towel and fine sand paper. Do not wash eggs
that are to be incubated.

Hatching eggs should be incubated as soon as
possible after they are laid. They can, however, be
stored up to 7 days with good results when held at a
temperature of 55 to 650F (13 to 180C) and a relative
humidity (RH) of 70 to 85%. Household refrigerators
are normally too cold and dry for holding eggs prior to
incubation.

Eggs should never be allowed to warm above 75F
(24C) until a few hours prior to being placed in the
incubator. Some embryonic growth can occur at 760F
(24.4C) or above. Embryonic growth at suboptimal
temperatures will be abnormal and will result in
increased embryo mortality.

Warm the eggs to room temperature (70 to 800F;
21 to 27C) before placing in the incubator. Do not
allow moisture to condense on the egg as it is warmed
because this will promote micro-organism passage
through the shell. A small fan to blow air across the
eggs during the warming process may help prevent
condensation.

Temperature

A still-air incubator should be operated at a
temperature of 101 to 1030F (38.3 to 39.4C), with the
bulb of the thermometer at the top of the eggs, or
about 1.5 to 2 inches above the screen. (Note:
Incubators with fans for circulation and
ventilation should be operated at 99.5F, or
37.5C). When the temperature is higher than this,
the incubation period will be decreased. If lower it
will be increased, and in either case hatchability will
be reduced. Ifthe temperature of the embryo exceeds
1040F (400C) for an extended period of time (several
days), death will usually occur. A temporary decrease
in egg temperature, as occurs during candling, will


slow development but does little or no harm to the
embryo. Most embryos can survive normal room
temperatures for up to 24 hours. However, low
temperature for longer periods may result in embryonic
death.

It is necessary that the temperature be kept as
close to 1010 to 1030F (38.3 to 39.40C as possible -
thus the need for an accurate thermometer and a
reliable heating control unit.

During Days 19 to 21 the incubator temperature
should be decreased about 1F (0.60C). This
compensates for the increased heat produced by the
embryo at this time. If there are younger embryos in
the same incubator, the temperature should remain
at the higher setting.

It is important to note that each incubator is
different. Through experience, the operator will be
able to determine the best operating conditions for
that particular incubator. For example, if the first
hatch of chicks comes off at 20 days instead of the
normal 21 days, the incubator was too warm and the
operating temperature should be lowered about 1F
(0.6C) for the next hatch. If the chicks required more
than 21 days to hatch, the incubator was too cool and
the temperature should be raised about 1F (0.60C).

Normally, chicks pip the shell on the nineteenth
or twentieth day, emerge from the shell on the
twentieth or twenty-first day, and are dry and fluffed
out and ready to be removed from the incubator by the
end of the twenty-first day.

Do not place the incubator in drafts or direct
sunlight, or allow it to be subjected to other conditions
that might cause fluctuations in temperature. Most
incubators operate best when the room temperature
is maintained at 750 to 800F (24 to 270C). In case of a
power failure, it is most crucial to provide adequate
ventilation, even if it causes the temperature to
decrease more.

Humidity

To control moisture/egg weight loss, it is usually
necessary to add moisture to the air of the incubator.
This can be done by filling a small pan (pie pan or cake
pan) with water to a depth of about 0.5" and placing
it under the egg tray. Use warm water when adding
to the pan. The eggs of most domestic species should


Page 5






Circular 813


INCUBATING AND HATCHING EGGS

Fertile Eggs

A supply of fertile eggs may be obtained from
hatcheries or from any poultry flock where roosters
are being kept with the hens. Eggs purchased from
food stores are not fertile and therefore will not hatch.
Eggs that are cracked, abnormal, dirty or covered
with oils or other sealants should not be incubated. If
eggs are soiled, they may be dry cleaned with a clean
paper towel and fine sand paper. Do not wash eggs
that are to be incubated.

Hatching eggs should be incubated as soon as
possible after they are laid. They can, however, be
stored up to 7 days with good results when held at a
temperature of 55 to 650F (13 to 180C) and a relative
humidity (RH) of 70 to 85%. Household refrigerators
are normally too cold and dry for holding eggs prior to
incubation.

Eggs should never be allowed to warm above 75F
(24C) until a few hours prior to being placed in the
incubator. Some embryonic growth can occur at 760F
(24.4C) or above. Embryonic growth at suboptimal
temperatures will be abnormal and will result in
increased embryo mortality.

Warm the eggs to room temperature (70 to 800F;
21 to 27C) before placing in the incubator. Do not
allow moisture to condense on the egg as it is warmed
because this will promote micro-organism passage
through the shell. A small fan to blow air across the
eggs during the warming process may help prevent
condensation.

Temperature

A still-air incubator should be operated at a
temperature of 101 to 1030F (38.3 to 39.4C), with the
bulb of the thermometer at the top of the eggs, or
about 1.5 to 2 inches above the screen. (Note:
Incubators with fans for circulation and
ventilation should be operated at 99.5F, or
37.5C). When the temperature is higher than this,
the incubation period will be decreased. If lower it
will be increased, and in either case hatchability will
be reduced. Ifthe temperature of the embryo exceeds
1040F (400C) for an extended period of time (several
days), death will usually occur. A temporary decrease
in egg temperature, as occurs during candling, will


slow development but does little or no harm to the
embryo. Most embryos can survive normal room
temperatures for up to 24 hours. However, low
temperature for longer periods may result in embryonic
death.

It is necessary that the temperature be kept as
close to 1010 to 1030F (38.3 to 39.40C as possible -
thus the need for an accurate thermometer and a
reliable heating control unit.

During Days 19 to 21 the incubator temperature
should be decreased about 1F (0.60C). This
compensates for the increased heat produced by the
embryo at this time. If there are younger embryos in
the same incubator, the temperature should remain
at the higher setting.

It is important to note that each incubator is
different. Through experience, the operator will be
able to determine the best operating conditions for
that particular incubator. For example, if the first
hatch of chicks comes off at 20 days instead of the
normal 21 days, the incubator was too warm and the
operating temperature should be lowered about 1F
(0.6C) for the next hatch. If the chicks required more
than 21 days to hatch, the incubator was too cool and
the temperature should be raised about 1F (0.60C).

Normally, chicks pip the shell on the nineteenth
or twentieth day, emerge from the shell on the
twentieth or twenty-first day, and are dry and fluffed
out and ready to be removed from the incubator by the
end of the twenty-first day.

Do not place the incubator in drafts or direct
sunlight, or allow it to be subjected to other conditions
that might cause fluctuations in temperature. Most
incubators operate best when the room temperature
is maintained at 750 to 800F (24 to 270C). In case of a
power failure, it is most crucial to provide adequate
ventilation, even if it causes the temperature to
decrease more.

Humidity

To control moisture/egg weight loss, it is usually
necessary to add moisture to the air of the incubator.
This can be done by filling a small pan (pie pan or cake
pan) with water to a depth of about 0.5" and placing
it under the egg tray. Use warm water when adding
to the pan. The eggs of most domestic species should


Page 5






Circular 813


INCUBATING AND HATCHING EGGS

Fertile Eggs

A supply of fertile eggs may be obtained from
hatcheries or from any poultry flock where roosters
are being kept with the hens. Eggs purchased from
food stores are not fertile and therefore will not hatch.
Eggs that are cracked, abnormal, dirty or covered
with oils or other sealants should not be incubated. If
eggs are soiled, they may be dry cleaned with a clean
paper towel and fine sand paper. Do not wash eggs
that are to be incubated.

Hatching eggs should be incubated as soon as
possible after they are laid. They can, however, be
stored up to 7 days with good results when held at a
temperature of 55 to 650F (13 to 180C) and a relative
humidity (RH) of 70 to 85%. Household refrigerators
are normally too cold and dry for holding eggs prior to
incubation.

Eggs should never be allowed to warm above 75F
(24C) until a few hours prior to being placed in the
incubator. Some embryonic growth can occur at 760F
(24.4C) or above. Embryonic growth at suboptimal
temperatures will be abnormal and will result in
increased embryo mortality.

Warm the eggs to room temperature (70 to 800F;
21 to 27C) before placing in the incubator. Do not
allow moisture to condense on the egg as it is warmed
because this will promote micro-organism passage
through the shell. A small fan to blow air across the
eggs during the warming process may help prevent
condensation.

Temperature

A still-air incubator should be operated at a
temperature of 101 to 1030F (38.3 to 39.4C), with the
bulb of the thermometer at the top of the eggs, or
about 1.5 to 2 inches above the screen. (Note:
Incubators with fans for circulation and
ventilation should be operated at 99.5F, or
37.5C). When the temperature is higher than this,
the incubation period will be decreased. If lower it
will be increased, and in either case hatchability will
be reduced. Ifthe temperature of the embryo exceeds
1040F (400C) for an extended period of time (several
days), death will usually occur. A temporary decrease
in egg temperature, as occurs during candling, will


slow development but does little or no harm to the
embryo. Most embryos can survive normal room
temperatures for up to 24 hours. However, low
temperature for longer periods may result in embryonic
death.

It is necessary that the temperature be kept as
close to 1010 to 1030F (38.3 to 39.40C as possible -
thus the need for an accurate thermometer and a
reliable heating control unit.

During Days 19 to 21 the incubator temperature
should be decreased about 1F (0.60C). This
compensates for the increased heat produced by the
embryo at this time. If there are younger embryos in
the same incubator, the temperature should remain
at the higher setting.

It is important to note that each incubator is
different. Through experience, the operator will be
able to determine the best operating conditions for
that particular incubator. For example, if the first
hatch of chicks comes off at 20 days instead of the
normal 21 days, the incubator was too warm and the
operating temperature should be lowered about 1F
(0.6C) for the next hatch. If the chicks required more
than 21 days to hatch, the incubator was too cool and
the temperature should be raised about 1F (0.60C).

Normally, chicks pip the shell on the nineteenth
or twentieth day, emerge from the shell on the
twentieth or twenty-first day, and are dry and fluffed
out and ready to be removed from the incubator by the
end of the twenty-first day.

Do not place the incubator in drafts or direct
sunlight, or allow it to be subjected to other conditions
that might cause fluctuations in temperature. Most
incubators operate best when the room temperature
is maintained at 750 to 800F (24 to 270C). In case of a
power failure, it is most crucial to provide adequate
ventilation, even if it causes the temperature to
decrease more.

Humidity

To control moisture/egg weight loss, it is usually
necessary to add moisture to the air of the incubator.
This can be done by filling a small pan (pie pan or cake
pan) with water to a depth of about 0.5" and placing
it under the egg tray. Use warm water when adding
to the pan. The eggs of most domestic species should


Page 5






Circular 813


INCUBATING AND HATCHING EGGS

Fertile Eggs

A supply of fertile eggs may be obtained from
hatcheries or from any poultry flock where roosters
are being kept with the hens. Eggs purchased from
food stores are not fertile and therefore will not hatch.
Eggs that are cracked, abnormal, dirty or covered
with oils or other sealants should not be incubated. If
eggs are soiled, they may be dry cleaned with a clean
paper towel and fine sand paper. Do not wash eggs
that are to be incubated.

Hatching eggs should be incubated as soon as
possible after they are laid. They can, however, be
stored up to 7 days with good results when held at a
temperature of 55 to 650F (13 to 180C) and a relative
humidity (RH) of 70 to 85%. Household refrigerators
are normally too cold and dry for holding eggs prior to
incubation.

Eggs should never be allowed to warm above 75F
(24C) until a few hours prior to being placed in the
incubator. Some embryonic growth can occur at 760F
(24.4C) or above. Embryonic growth at suboptimal
temperatures will be abnormal and will result in
increased embryo mortality.

Warm the eggs to room temperature (70 to 800F;
21 to 27C) before placing in the incubator. Do not
allow moisture to condense on the egg as it is warmed
because this will promote micro-organism passage
through the shell. A small fan to blow air across the
eggs during the warming process may help prevent
condensation.

Temperature

A still-air incubator should be operated at a
temperature of 101 to 1030F (38.3 to 39.4C), with the
bulb of the thermometer at the top of the eggs, or
about 1.5 to 2 inches above the screen. (Note:
Incubators with fans for circulation and
ventilation should be operated at 99.5F, or
37.5C). When the temperature is higher than this,
the incubation period will be decreased. If lower it
will be increased, and in either case hatchability will
be reduced. Ifthe temperature of the embryo exceeds
1040F (400C) for an extended period of time (several
days), death will usually occur. A temporary decrease
in egg temperature, as occurs during candling, will


slow development but does little or no harm to the
embryo. Most embryos can survive normal room
temperatures for up to 24 hours. However, low
temperature for longer periods may result in embryonic
death.

It is necessary that the temperature be kept as
close to 1010 to 1030F (38.3 to 39.40C as possible -
thus the need for an accurate thermometer and a
reliable heating control unit.

During Days 19 to 21 the incubator temperature
should be decreased about 1F (0.60C). This
compensates for the increased heat produced by the
embryo at this time. If there are younger embryos in
the same incubator, the temperature should remain
at the higher setting.

It is important to note that each incubator is
different. Through experience, the operator will be
able to determine the best operating conditions for
that particular incubator. For example, if the first
hatch of chicks comes off at 20 days instead of the
normal 21 days, the incubator was too warm and the
operating temperature should be lowered about 1F
(0.6C) for the next hatch. If the chicks required more
than 21 days to hatch, the incubator was too cool and
the temperature should be raised about 1F (0.60C).

Normally, chicks pip the shell on the nineteenth
or twentieth day, emerge from the shell on the
twentieth or twenty-first day, and are dry and fluffed
out and ready to be removed from the incubator by the
end of the twenty-first day.

Do not place the incubator in drafts or direct
sunlight, or allow it to be subjected to other conditions
that might cause fluctuations in temperature. Most
incubators operate best when the room temperature
is maintained at 750 to 800F (24 to 270C). In case of a
power failure, it is most crucial to provide adequate
ventilation, even if it causes the temperature to
decrease more.

Humidity

To control moisture/egg weight loss, it is usually
necessary to add moisture to the air of the incubator.
This can be done by filling a small pan (pie pan or cake
pan) with water to a depth of about 0.5" and placing
it under the egg tray. Use warm water when adding
to the pan. The eggs of most domestic species should


Page 5






Circular 813


lose approximately 12% of their initial weight by
three days prior to expected hatching (Day 19 in the
chicken). Egg weight loss is the best indicator of
incubator humidity. Adjustments can be made in
water surface area of the evaporation pan to obtain
proper weight loss.

As eggs lose moisture and weight, the air cell (in
the large end) increases in size. Figure 2 shows the
comparative size of the air cell in an egg on the
seventh, fourteenth and eighteenth days ofincubation.
Change in air cell
size also can be 7 *........
used to estimate 14 ......**
egg weight loss
and needed 18 ....
changes in
humidity. If the
air cell is too slow
in enlarging, too
much moisture is
present. On the Figure 2.
other hand, if the
air cell is too large, more moisture is needed. Size of
the air cell ca n be determined by candling (placing the
egg before a strong light see section on candling
below).

It is advisable to add an extra pan of warm water,
or to sprinkle the eggs lightly with warm water, at the
time ofhatching to increase humidity in the incubator
and prevent the chicks from sticking to the shell. This
is done when the first egg pips. Best results are
achieved when the relative humidity is 60 to 61% RH
(1020F dry bulb and 890F wet bulb; 99.5F dry bulb
and 870F wet bulb) for the first 18 days and then
increased to 72% RH (93 or 90F wetbulb, respectively)
for the remainder of the incubation period.

Incubator conditions used for chickens are also
satisfactory for most domestically raised species such
as turkeys, ducks, geese, guineas, quail and pheasants.
However, ducks and geese need higher humidity
throughout incubation than do other species.
Incubation times vary considerably between species.

Incubation times and temperature and
humidity requirements for various species are shown
in Table 1.


Table 1. Incubation Time, Temperature, and Hu-
midity Required for Various Species (Force draft
Incubator)
Days E WB


Chicken
Turkey
Duck (Mallard)
Muscovy duck
Geese
Swan
Bobwhite quail
Coturnix quail
(Japanese)
Guinea
Pheasant
Chukar 23
Peafowl 28-30
Ostrich
Emu
Rhea
Pigeon


21
28
28
35+
30-35
42
23-24
16-17

28
23-24
99.5
99.5
42
48-56
38-42
17


99.5
99.5
99.1
99.1
99.0
99.0
100.0
99.5

99.5
99.5
86
87
97.5
98.0
98.0
--


Position of Eggs

Eggs will hatch poorly unless they are turned
several times each day from the first through the
eighteenth day of incubation. This prevents the
developing embryo from st icking to the shell, prevents
malpositions, and promotes proper development of
the embryonic membranes. Lack of turning after 13
days usually causes minimal problems.

In small incubators there are two ways that
turning may be done. The eggs may be marked on one
side and laid in a horizontal position in the incubator
with the marked side up. 'Turn the eggs an odd
number of times (3 or 5) each day. This will prevent
havingthe egg laying in the same position each night,
which is likely to be the longer period. All eggs should
have the marked side down at the same time. This
system will ensure getting all eggs turned. Alternate
the direction of turning. Turning eggs the same
direction each time may result in undue twisting of
the embryonic membranes and possible death of the
embryo.

The other method of turning eggs is to place the
eggs small end down in egg cartons which have had
the top removed. The carton may be tilted first one
direction and then the other to accomplish turning.
This is acceptable for incubators having a circulating
fan, but for still-air incubators it results in the eggs


Page 6






Cidwr 813


being at different levels and, therefore, at different
temperatures with each move.

Ventilation

At the time of laying, the fertilized egg contains
all the materials necessary for embryonic development,
except sufficient air. The embryo obtains the oxygen
necessary for growth from the air that passes through
the tiny pores of the egg shell. Eggs to be used for
hatching should be kept free of oil, grease or other
foreign materials that would seal the pores and reduce
air exchange.

In operating the incubator, be sure that the
machine is properly ventilated at all times. There
should be four vents (openings 1 inch in diameter) for
ventilation. It is desirable to adjust these openings;
halfway the first 18 days of incubation and fully open
the final 3 days. Adjustments should be made
according to the experience in previous hatches. Be
sure that the incubator is placed in a well-ventilated
room.

Candling Incubated Eggs

Incubated eggs are candled to determine whether
or not they are fertile and to check on the growth and
development of the embryo. Fertility is more easily
determined in white-shelled eggs, which may be
candled on the third or fourth day of incubation.
Brown shelled eggs can be checked on the fifth or sixth
day of incubation.

When candling fertile eggs on the fourth and fifth
day of incubation, the embryo appears as a small
reddish area with blood vessels extending out into the
egg. At this stage the embryo gives the appearance of
a large red spider.

Infertile eggs will appear "clear" with no embryo
development. These eggs show some yolk shadow but
are, in general, uniformly light in appearance.

In some eggs the embryo will die after a few days
of development, but before there is blood formation
(before 2 days of incubation). When candled from the
large end after the third day these eggs will be light in
the large end and darker on the small end, but the
embryo will not be visible. When the embryo dies
after blood is present, the blood will accumulate at the
outer ends of the blood vessels and will form a blood


ring or a streak. This will turn dark as the eggBstart
to decompose. Eggs that appear to contain bacterial
or mold contamination may explode and, therefme,
should be removed from the incubator.

When checking embryo development, the large
end of the egg should be placed to the opening of the
chandler since the embryo will be found near the air
cell. In eggs incubated horizontally, the embryo wil
tend to be farther down on one side. Care alomlbe
takennottotwistortwirltheeggbecausethiscan
damage the embryonic membranes. The candlig
of eggs should be done in a darkened room.

Egg candlers may be purchased from poultry
equipment dealers or they may be made. A bright
flashlight adapted to fit the large end of an egg is
satisfactory. A chandler may also be made by placing
a 60-watt light bulb in a small box with an opening
drilled in the side. This opening should be 1" to 1.25
in diameter with the light bulb centered directly on
the hole. A shoe box lined with aluminum fil and
with small holes cut in the top (to let heatescape)may
be used (Diagram H).


Avery bright candlercan be madebycoveringthe
lens of a slide projector with a piece ofcardboard with
a 1" hole in it. However, care should be taken tohold
the egg to the light for only a few seconds otherwise
the embryonic membranes and embryo can be
damaged bytheintenseheatproducedbytheselighla


Page 7


990 5 4
Cp 4 4
CP 0 i 4
a 0045 C






Cidwr 813


being at different levels and, therefore, at different
temperatures with each move.

Ventilation

At the time of laying, the fertilized egg contains
all the materials necessary for embryonic development,
except sufficient air. The embryo obtains the oxygen
necessary for growth from the air that passes through
the tiny pores of the egg shell. Eggs to be used for
hatching should be kept free of oil, grease or other
foreign materials that would seal the pores and reduce
air exchange.

In operating the incubator, be sure that the
machine is properly ventilated at all times. There
should be four vents (openings 1 inch in diameter) for
ventilation. It is desirable to adjust these openings;
halfway the first 18 days of incubation and fully open
the final 3 days. Adjustments should be made
according to the experience in previous hatches. Be
sure that the incubator is placed in a well-ventilated
room.

Candling Incubated Eggs

Incubated eggs are candled to determine whether
or not they are fertile and to check on the growth and
development of the embryo. Fertility is more easily
determined in white-shelled eggs, which may be
candled on the third or fourth day of incubation.
Brown shelled eggs can be checked on the fifth or sixth
day of incubation.

When candling fertile eggs on the fourth and fifth
day of incubation, the embryo appears as a small
reddish area with blood vessels extending out into the
egg. At this stage the embryo gives the appearance of
a large red spider.

Infertile eggs will appear "clear" with no embryo
development. These eggs show some yolk shadow but
are, in general, uniformly light in appearance.

In some eggs the embryo will die after a few days
of development, but before there is blood formation
(before 2 days of incubation). When candled from the
large end after the third day these eggs will be light in
the large end and darker on the small end, but the
embryo will not be visible. When the embryo dies
after blood is present, the blood will accumulate at the
outer ends of the blood vessels and will form a blood


ring or a streak. This will turn dark as the eggBstart
to decompose. Eggs that appear to contain bacterial
or mold contamination may explode and, therefme,
should be removed from the incubator.

When checking embryo development, the large
end of the egg should be placed to the opening of the
chandler since the embryo will be found near the air
cell. In eggs incubated horizontally, the embryo wil
tend to be farther down on one side. Care alomlbe
takennottotwistortwirltheeggbecausethiscan
damage the embryonic membranes. The candlig
of eggs should be done in a darkened room.

Egg candlers may be purchased from poultry
equipment dealers or they may be made. A bright
flashlight adapted to fit the large end of an egg is
satisfactory. A chandler may also be made by placing
a 60-watt light bulb in a small box with an opening
drilled in the side. This opening should be 1" to 1.25
in diameter with the light bulb centered directly on
the hole. A shoe box lined with aluminum fil and
with small holes cut in the top (to let heatescape)may
be used (Diagram H).


Avery bright candlercan be madebycoveringthe
lens of a slide projector with a piece ofcardboard with
a 1" hole in it. However, care should be taken tohold
the egg to the light for only a few seconds otherwise
the embryonic membranes and embryo can be
damaged bytheintenseheatproducedbytheselighla


Page 7


990 5 4
Cp 4 4
CP 0 i 4
a 0045 C






Circular 813


CARE OF CHICKS AFTER HATCHING


To teachers, leaders or parents: Make
arrangements for proper care of the chicks well
in advance of the expected hatching date. Have
starter feed, water fountains, brooder and a suitable
enclosure ready for the chicks when they hatch. If the
chicks are to be given to children, be sure that they
and their families are prepared to give the chicks
adequate care. It is best to make arrangements for
chick care before the eggs are placed in the incubator.

Brooder House

Before the chicks hatch, have a room or area that
can be used for brooding the chicks. An empty space
in a dwelling, garage, barn, or other building can be
remodeled for use in brooding.

The brooder house should be well ventilated, kept
dry and have access to electricity.

Allow 1 square foot of floor space per chick. Thus,
a pen or area that is 10' x 10' will house 100 baby
chicks.

If an old brooder house is used, it should be
cleaned and then disinfected. Hot lye water is one of
the best disinfecting agents available. Use one small
can of lye to 12-15 gallons of water. Another common
disinfectant that can be used is household bleach
(sodium hypochlorite) diluted 1 to 4 with water. After
cleaning and disinfecting, allow the house to dry
thoroughly. If only a small number of chicks are to be
brooded, a clean cardboard box can serve as a
temporary brooding area; however, the box should be
sufficiently large to permit the chicks to move away
'from the heat source.

Litter

After the brooder area has been cleaned,
disinfected, and is dry, cover the floor with 4 to 6
inches of dry litter. Wood shavings, sawdust, peanut
hulls, sugar cane bagasse, or chopped straw can be
used for litter material. Do not use newspapers or
other relatively smooth materials. The smooth surface
may result in spraddled legs or other leg problems,
especially in turkey, quail, pheasant or broiler chicks.


The brooder is a source of heat to keep the chicks
warm during the first 4 to 6 weeks of age. The time
will vary depending on season and breed or species of
bird. An infra-red heat lamp makes a simple, but
effective, brooder for 100 chicks.

Another inexpensive method of supplying heat is
to place a 100-watt light bulb inside a gallon metalcan
and place the can on the floor of the brooder house.
Two brooders of this type will be needed for each 100
chicks, depending on the brooder room temperature.
A 25- to 40-watt bulb inside a can is satisfactory in a
cardboard box brooder.

When hover-type brooders are used, the
temperature under the brooder should be 950F (350C)
during the first week of the chick's life, 90F (320C)
the second week, 850F (290C) the third week, and 80F
(27C) the fourth week. Chicks should be given an
opportunity to move toward or away from the heat
source and thereby find their own comfort zone.

By observing the chicks it can be determined if
they are comfortable. Chicks that are evenly
distributed over the floor and are busily eating and
drinking are comfortable and the brooder temperature
is adequate. If the chicks droop their wings, keep
their mouths open, and try to move away from the
heat source, the brooder is too hot and the heat should
be decreased. When chicks huddle together, pile up
and emit a loud chirp they are chilled and more heat
is needed. Chilling or overheating can result in
unthrifty chicks and a high mortality rate.

Chick Guard

A chick guard is a circular fence about 18 inches
high placed around the brooder to keep the chicks
confined to the source of heat and eliminate corners.
The guard can be made from cardboard, sheet metal
or other suitable material.

When using a heat lamp the guard should be 4 to
6 feet in diameter. It should be large enough to allow
the chicks to move away from the heat source as
needed to be comfortable. The guard can be removed
when the chicks are 5 to 8 days old.


Page 8


Brooder






Circular 813


CARE OF CHICKS AFTER HATCHING


To teachers, leaders or parents: Make
arrangements for proper care of the chicks well
in advance of the expected hatching date. Have
starter feed, water fountains, brooder and a suitable
enclosure ready for the chicks when they hatch. If the
chicks are to be given to children, be sure that they
and their families are prepared to give the chicks
adequate care. It is best to make arrangements for
chick care before the eggs are placed in the incubator.

Brooder House

Before the chicks hatch, have a room or area that
can be used for brooding the chicks. An empty space
in a dwelling, garage, barn, or other building can be
remodeled for use in brooding.

The brooder house should be well ventilated, kept
dry and have access to electricity.

Allow 1 square foot of floor space per chick. Thus,
a pen or area that is 10' x 10' will house 100 baby
chicks.

If an old brooder house is used, it should be
cleaned and then disinfected. Hot lye water is one of
the best disinfecting agents available. Use one small
can of lye to 12-15 gallons of water. Another common
disinfectant that can be used is household bleach
(sodium hypochlorite) diluted 1 to 4 with water. After
cleaning and disinfecting, allow the house to dry
thoroughly. If only a small number of chicks are to be
brooded, a clean cardboard box can serve as a
temporary brooding area; however, the box should be
sufficiently large to permit the chicks to move away
'from the heat source.

Litter

After the brooder area has been cleaned,
disinfected, and is dry, cover the floor with 4 to 6
inches of dry litter. Wood shavings, sawdust, peanut
hulls, sugar cane bagasse, or chopped straw can be
used for litter material. Do not use newspapers or
other relatively smooth materials. The smooth surface
may result in spraddled legs or other leg problems,
especially in turkey, quail, pheasant or broiler chicks.


The brooder is a source of heat to keep the chicks
warm during the first 4 to 6 weeks of age. The time
will vary depending on season and breed or species of
bird. An infra-red heat lamp makes a simple, but
effective, brooder for 100 chicks.

Another inexpensive method of supplying heat is
to place a 100-watt light bulb inside a gallon metalcan
and place the can on the floor of the brooder house.
Two brooders of this type will be needed for each 100
chicks, depending on the brooder room temperature.
A 25- to 40-watt bulb inside a can is satisfactory in a
cardboard box brooder.

When hover-type brooders are used, the
temperature under the brooder should be 950F (350C)
during the first week of the chick's life, 90F (320C)
the second week, 850F (290C) the third week, and 80F
(27C) the fourth week. Chicks should be given an
opportunity to move toward or away from the heat
source and thereby find their own comfort zone.

By observing the chicks it can be determined if
they are comfortable. Chicks that are evenly
distributed over the floor and are busily eating and
drinking are comfortable and the brooder temperature
is adequate. If the chicks droop their wings, keep
their mouths open, and try to move away from the
heat source, the brooder is too hot and the heat should
be decreased. When chicks huddle together, pile up
and emit a loud chirp they are chilled and more heat
is needed. Chilling or overheating can result in
unthrifty chicks and a high mortality rate.

Chick Guard

A chick guard is a circular fence about 18 inches
high placed around the brooder to keep the chicks
confined to the source of heat and eliminate corners.
The guard can be made from cardboard, sheet metal
or other suitable material.

When using a heat lamp the guard should be 4 to
6 feet in diameter. It should be large enough to allow
the chicks to move away from the heat source as
needed to be comfortable. The guard can be removed
when the chicks are 5 to 8 days old.


Page 8


Brooder






Circular 813


CARE OF CHICKS AFTER HATCHING


To teachers, leaders or parents: Make
arrangements for proper care of the chicks well
in advance of the expected hatching date. Have
starter feed, water fountains, brooder and a suitable
enclosure ready for the chicks when they hatch. If the
chicks are to be given to children, be sure that they
and their families are prepared to give the chicks
adequate care. It is best to make arrangements for
chick care before the eggs are placed in the incubator.

Brooder House

Before the chicks hatch, have a room or area that
can be used for brooding the chicks. An empty space
in a dwelling, garage, barn, or other building can be
remodeled for use in brooding.

The brooder house should be well ventilated, kept
dry and have access to electricity.

Allow 1 square foot of floor space per chick. Thus,
a pen or area that is 10' x 10' will house 100 baby
chicks.

If an old brooder house is used, it should be
cleaned and then disinfected. Hot lye water is one of
the best disinfecting agents available. Use one small
can of lye to 12-15 gallons of water. Another common
disinfectant that can be used is household bleach
(sodium hypochlorite) diluted 1 to 4 with water. After
cleaning and disinfecting, allow the house to dry
thoroughly. If only a small number of chicks are to be
brooded, a clean cardboard box can serve as a
temporary brooding area; however, the box should be
sufficiently large to permit the chicks to move away
'from the heat source.

Litter

After the brooder area has been cleaned,
disinfected, and is dry, cover the floor with 4 to 6
inches of dry litter. Wood shavings, sawdust, peanut
hulls, sugar cane bagasse, or chopped straw can be
used for litter material. Do not use newspapers or
other relatively smooth materials. The smooth surface
may result in spraddled legs or other leg problems,
especially in turkey, quail, pheasant or broiler chicks.


The brooder is a source of heat to keep the chicks
warm during the first 4 to 6 weeks of age. The time
will vary depending on season and breed or species of
bird. An infra-red heat lamp makes a simple, but
effective, brooder for 100 chicks.

Another inexpensive method of supplying heat is
to place a 100-watt light bulb inside a gallon metalcan
and place the can on the floor of the brooder house.
Two brooders of this type will be needed for each 100
chicks, depending on the brooder room temperature.
A 25- to 40-watt bulb inside a can is satisfactory in a
cardboard box brooder.

When hover-type brooders are used, the
temperature under the brooder should be 950F (350C)
during the first week of the chick's life, 90F (320C)
the second week, 850F (290C) the third week, and 80F
(27C) the fourth week. Chicks should be given an
opportunity to move toward or away from the heat
source and thereby find their own comfort zone.

By observing the chicks it can be determined if
they are comfortable. Chicks that are evenly
distributed over the floor and are busily eating and
drinking are comfortable and the brooder temperature
is adequate. If the chicks droop their wings, keep
their mouths open, and try to move away from the
heat source, the brooder is too hot and the heat should
be decreased. When chicks huddle together, pile up
and emit a loud chirp they are chilled and more heat
is needed. Chilling or overheating can result in
unthrifty chicks and a high mortality rate.

Chick Guard

A chick guard is a circular fence about 18 inches
high placed around the brooder to keep the chicks
confined to the source of heat and eliminate corners.
The guard can be made from cardboard, sheet metal
or other suitable material.

When using a heat lamp the guard should be 4 to
6 feet in diameter. It should be large enough to allow
the chicks to move away from the heat source as
needed to be comfortable. The guard can be removed
when the chicks are 5 to 8 days old.


Page 8


Brooder






Circular 813


CARE OF CHICKS AFTER HATCHING


To teachers, leaders or parents: Make
arrangements for proper care of the chicks well
in advance of the expected hatching date. Have
starter feed, water fountains, brooder and a suitable
enclosure ready for the chicks when they hatch. If the
chicks are to be given to children, be sure that they
and their families are prepared to give the chicks
adequate care. It is best to make arrangements for
chick care before the eggs are placed in the incubator.

Brooder House

Before the chicks hatch, have a room or area that
can be used for brooding the chicks. An empty space
in a dwelling, garage, barn, or other building can be
remodeled for use in brooding.

The brooder house should be well ventilated, kept
dry and have access to electricity.

Allow 1 square foot of floor space per chick. Thus,
a pen or area that is 10' x 10' will house 100 baby
chicks.

If an old brooder house is used, it should be
cleaned and then disinfected. Hot lye water is one of
the best disinfecting agents available. Use one small
can of lye to 12-15 gallons of water. Another common
disinfectant that can be used is household bleach
(sodium hypochlorite) diluted 1 to 4 with water. After
cleaning and disinfecting, allow the house to dry
thoroughly. If only a small number of chicks are to be
brooded, a clean cardboard box can serve as a
temporary brooding area; however, the box should be
sufficiently large to permit the chicks to move away
'from the heat source.

Litter

After the brooder area has been cleaned,
disinfected, and is dry, cover the floor with 4 to 6
inches of dry litter. Wood shavings, sawdust, peanut
hulls, sugar cane bagasse, or chopped straw can be
used for litter material. Do not use newspapers or
other relatively smooth materials. The smooth surface
may result in spraddled legs or other leg problems,
especially in turkey, quail, pheasant or broiler chicks.


The brooder is a source of heat to keep the chicks
warm during the first 4 to 6 weeks of age. The time
will vary depending on season and breed or species of
bird. An infra-red heat lamp makes a simple, but
effective, brooder for 100 chicks.

Another inexpensive method of supplying heat is
to place a 100-watt light bulb inside a gallon metalcan
and place the can on the floor of the brooder house.
Two brooders of this type will be needed for each 100
chicks, depending on the brooder room temperature.
A 25- to 40-watt bulb inside a can is satisfactory in a
cardboard box brooder.

When hover-type brooders are used, the
temperature under the brooder should be 950F (350C)
during the first week of the chick's life, 90F (320C)
the second week, 850F (290C) the third week, and 80F
(27C) the fourth week. Chicks should be given an
opportunity to move toward or away from the heat
source and thereby find their own comfort zone.

By observing the chicks it can be determined if
they are comfortable. Chicks that are evenly
distributed over the floor and are busily eating and
drinking are comfortable and the brooder temperature
is adequate. If the chicks droop their wings, keep
their mouths open, and try to move away from the
heat source, the brooder is too hot and the heat should
be decreased. When chicks huddle together, pile up
and emit a loud chirp they are chilled and more heat
is needed. Chilling or overheating can result in
unthrifty chicks and a high mortality rate.

Chick Guard

A chick guard is a circular fence about 18 inches
high placed around the brooder to keep the chicks
confined to the source of heat and eliminate corners.
The guard can be made from cardboard, sheet metal
or other suitable material.

When using a heat lamp the guard should be 4 to
6 feet in diameter. It should be large enough to allow
the chicks to move away from the heat source as
needed to be comfortable. The guard can be removed
when the chicks are 5 to 8 days old.


Page 8


Brooder






Circular 813


CARE OF CHICKS AFTER HATCHING


To teachers, leaders or parents: Make
arrangements for proper care of the chicks well
in advance of the expected hatching date. Have
starter feed, water fountains, brooder and a suitable
enclosure ready for the chicks when they hatch. If the
chicks are to be given to children, be sure that they
and their families are prepared to give the chicks
adequate care. It is best to make arrangements for
chick care before the eggs are placed in the incubator.

Brooder House

Before the chicks hatch, have a room or area that
can be used for brooding the chicks. An empty space
in a dwelling, garage, barn, or other building can be
remodeled for use in brooding.

The brooder house should be well ventilated, kept
dry and have access to electricity.

Allow 1 square foot of floor space per chick. Thus,
a pen or area that is 10' x 10' will house 100 baby
chicks.

If an old brooder house is used, it should be
cleaned and then disinfected. Hot lye water is one of
the best disinfecting agents available. Use one small
can of lye to 12-15 gallons of water. Another common
disinfectant that can be used is household bleach
(sodium hypochlorite) diluted 1 to 4 with water. After
cleaning and disinfecting, allow the house to dry
thoroughly. If only a small number of chicks are to be
brooded, a clean cardboard box can serve as a
temporary brooding area; however, the box should be
sufficiently large to permit the chicks to move away
'from the heat source.

Litter

After the brooder area has been cleaned,
disinfected, and is dry, cover the floor with 4 to 6
inches of dry litter. Wood shavings, sawdust, peanut
hulls, sugar cane bagasse, or chopped straw can be
used for litter material. Do not use newspapers or
other relatively smooth materials. The smooth surface
may result in spraddled legs or other leg problems,
especially in turkey, quail, pheasant or broiler chicks.


The brooder is a source of heat to keep the chicks
warm during the first 4 to 6 weeks of age. The time
will vary depending on season and breed or species of
bird. An infra-red heat lamp makes a simple, but
effective, brooder for 100 chicks.

Another inexpensive method of supplying heat is
to place a 100-watt light bulb inside a gallon metalcan
and place the can on the floor of the brooder house.
Two brooders of this type will be needed for each 100
chicks, depending on the brooder room temperature.
A 25- to 40-watt bulb inside a can is satisfactory in a
cardboard box brooder.

When hover-type brooders are used, the
temperature under the brooder should be 950F (350C)
during the first week of the chick's life, 90F (320C)
the second week, 850F (290C) the third week, and 80F
(27C) the fourth week. Chicks should be given an
opportunity to move toward or away from the heat
source and thereby find their own comfort zone.

By observing the chicks it can be determined if
they are comfortable. Chicks that are evenly
distributed over the floor and are busily eating and
drinking are comfortable and the brooder temperature
is adequate. If the chicks droop their wings, keep
their mouths open, and try to move away from the
heat source, the brooder is too hot and the heat should
be decreased. When chicks huddle together, pile up
and emit a loud chirp they are chilled and more heat
is needed. Chilling or overheating can result in
unthrifty chicks and a high mortality rate.

Chick Guard

A chick guard is a circular fence about 18 inches
high placed around the brooder to keep the chicks
confined to the source of heat and eliminate corners.
The guard can be made from cardboard, sheet metal
or other suitable material.

When using a heat lamp the guard should be 4 to
6 feet in diameter. It should be large enough to allow
the chicks to move away from the heat source as
needed to be comfortable. The guard can be removed
when the chicks are 5 to 8 days old.


Page 8


Brooder






ckicum. 813


Feeding

For chicks of an egg-type strain, use a good
commercial all-mash or crumble starter feed
containing a coccidiostat for the first 6 to 8 weeks, and
then change to an all-mash or crumble grower feed.
Continue to feed pullets the grower mash until they
start to lay, then change to a layer mash. Cockerels
can be fed either grower or layer diets as adults. Keep
feed before the birds at all times.

For chicks of a meat-type strain (broilers), use a
good commercial broiler starter feed containing a
coccidiostat for the first 4 or 5 weeks. Thereafter until
slaughter, feed a finisher diet which contains no
coccidiostat or other drug.

Proper feeding of 100 baby chicks for the first 2
weeks will require two feed troughs (baby chick size),
each 2 feet long, or two hanging cylindrical feeders
with shallow pans. Feed also may be placed in
shallow pans or cardboard egg flats for the first 2 or 3
days. When the chicks are 2 weeks old, change to
medium-size feeders, using two 4-foot feeders, or four
hanging feeders. After the birds are 12 weeks old,
provide one 4-foot feeder or one hanging feeder for
each 25 birds. Adequate feeder space is important to
prevent stress and to allow chicks to grow properly.

Avoid feed wastage. Feeders need to be full
during the first day or two of the chick's life so that the
chicks can easily find the feed. From then on, feeders
should be filled from one-half to two-thirds full.
Avoiding feed wastage will reduce feed cost. About 20
pounds of feed (starter and grower) are required to
grow a pullet from 1 day to 5 months old, or about the
time the pullet should start laying.

Under ideal conditions, broilers can be grown on
2 pounds or less of feed for each pound of body weight.

Watering

A plentiful supply of cool, clean drinking water is
one of the most important requirements in raising
chicks and the least expensive. Be sure your chicks
have adequate water all day long, every day. One
hundred chicks will need two 1-gallon waterers. Place
the waterers on a short piece of board (1" x 10" x10")
to help keep litter out of the water and thus keep the
water clean. The waterer should be kept level to
prevent leakage and wet litter.


When chicks are about 4 weeks old, change to
larger waterers. Two 3-gallon double-wall waters,
or one automatic waterer will supply the chicks daily
needforwater. These samelargeorautomaticwaterer
can be used during the growing and laying period.
Clean the waterers daily and keep them in a shaded
location. Always have a minimum of two waterers
available to the chicks in case of failure of one.

For broilers, change to four larger waterers per
100 chicks at 2 weeks of age.

Some Helpful Hints

Watch the chicks closely the first day and nightto
see that they are comfortable. Theyshouldbeprovided
with a warm, dry place with feed and water that is
easily found.

Don't fill the feed troughs too fall after the first 2
days or the chicks will scratch the feed outandwasteiL

Stir and keep litter dry. Remove anyJitter that
becomes wet. Wet litter is an excellent, place fEr
disease organisms and parasites to grow.

After the first week, increase the amoMnt ofairin
the brooder house to allow for good ventilation.

Watch for coccidiosis in the chicks. This disease
generally affects chicks between 2 and 10 weeks of
age. Symptoms include bloody droppings, ruffled
feathers, drooped wings and the chick i usuallypals,
cold and listless. To control the disease, use starter
and grower feeds that contain a coccidiostat

Cannibalism (birds pecking one another until
blood shows) can become a problem if birds become
overheated, overcrowded, orundrfed. Provideplenty
of fresh air and increase floor space to 2-3 square feet
per bird as chicks grow. Trim the chicks' beaks to
prevent cannibalism. Using stop-picksalves willhlp
control cannibalism.

Separate cockerels from the pullets (in egg-type
breeds) when 6 to 8 weeks ofage. When the cockerels
weigh about 3 pounds each, they should be sold or
slaughtered.

Vaccinate egg-type birds against fowl pox when
they are 6 to 9 weeks old. Vaccination is simple and
inexpensive. Follow directions on the vaccine


Page 9






ckicum. 813


Feeding

For chicks of an egg-type strain, use a good
commercial all-mash or crumble starter feed
containing a coccidiostat for the first 6 to 8 weeks, and
then change to an all-mash or crumble grower feed.
Continue to feed pullets the grower mash until they
start to lay, then change to a layer mash. Cockerels
can be fed either grower or layer diets as adults. Keep
feed before the birds at all times.

For chicks of a meat-type strain (broilers), use a
good commercial broiler starter feed containing a
coccidiostat for the first 4 or 5 weeks. Thereafter until
slaughter, feed a finisher diet which contains no
coccidiostat or other drug.

Proper feeding of 100 baby chicks for the first 2
weeks will require two feed troughs (baby chick size),
each 2 feet long, or two hanging cylindrical feeders
with shallow pans. Feed also may be placed in
shallow pans or cardboard egg flats for the first 2 or 3
days. When the chicks are 2 weeks old, change to
medium-size feeders, using two 4-foot feeders, or four
hanging feeders. After the birds are 12 weeks old,
provide one 4-foot feeder or one hanging feeder for
each 25 birds. Adequate feeder space is important to
prevent stress and to allow chicks to grow properly.

Avoid feed wastage. Feeders need to be full
during the first day or two of the chick's life so that the
chicks can easily find the feed. From then on, feeders
should be filled from one-half to two-thirds full.
Avoiding feed wastage will reduce feed cost. About 20
pounds of feed (starter and grower) are required to
grow a pullet from 1 day to 5 months old, or about the
time the pullet should start laying.

Under ideal conditions, broilers can be grown on
2 pounds or less of feed for each pound of body weight.

Watering

A plentiful supply of cool, clean drinking water is
one of the most important requirements in raising
chicks and the least expensive. Be sure your chicks
have adequate water all day long, every day. One
hundred chicks will need two 1-gallon waterers. Place
the waterers on a short piece of board (1" x 10" x10")
to help keep litter out of the water and thus keep the
water clean. The waterer should be kept level to
prevent leakage and wet litter.


When chicks are about 4 weeks old, change to
larger waterers. Two 3-gallon double-wall waters,
or one automatic waterer will supply the chicks daily
needforwater. These samelargeorautomaticwaterer
can be used during the growing and laying period.
Clean the waterers daily and keep them in a shaded
location. Always have a minimum of two waterers
available to the chicks in case of failure of one.

For broilers, change to four larger waterers per
100 chicks at 2 weeks of age.

Some Helpful Hints

Watch the chicks closely the first day and nightto
see that they are comfortable. Theyshouldbeprovided
with a warm, dry place with feed and water that is
easily found.

Don't fill the feed troughs too fall after the first 2
days or the chicks will scratch the feed outandwasteiL

Stir and keep litter dry. Remove anyJitter that
becomes wet. Wet litter is an excellent, place fEr
disease organisms and parasites to grow.

After the first week, increase the amoMnt ofairin
the brooder house to allow for good ventilation.

Watch for coccidiosis in the chicks. This disease
generally affects chicks between 2 and 10 weeks of
age. Symptoms include bloody droppings, ruffled
feathers, drooped wings and the chick i usuallypals,
cold and listless. To control the disease, use starter
and grower feeds that contain a coccidiostat

Cannibalism (birds pecking one another until
blood shows) can become a problem if birds become
overheated, overcrowded, orundrfed. Provideplenty
of fresh air and increase floor space to 2-3 square feet
per bird as chicks grow. Trim the chicks' beaks to
prevent cannibalism. Using stop-picksalves willhlp
control cannibalism.

Separate cockerels from the pullets (in egg-type
breeds) when 6 to 8 weeks ofage. When the cockerels
weigh about 3 pounds each, they should be sold or
slaughtered.

Vaccinate egg-type birds against fowl pox when
they are 6 to 9 weeks old. Vaccination is simple and
inexpensive. Follow directions on the vaccine


Page 9






ckicum. 813


Feeding

For chicks of an egg-type strain, use a good
commercial all-mash or crumble starter feed
containing a coccidiostat for the first 6 to 8 weeks, and
then change to an all-mash or crumble grower feed.
Continue to feed pullets the grower mash until they
start to lay, then change to a layer mash. Cockerels
can be fed either grower or layer diets as adults. Keep
feed before the birds at all times.

For chicks of a meat-type strain (broilers), use a
good commercial broiler starter feed containing a
coccidiostat for the first 4 or 5 weeks. Thereafter until
slaughter, feed a finisher diet which contains no
coccidiostat or other drug.

Proper feeding of 100 baby chicks for the first 2
weeks will require two feed troughs (baby chick size),
each 2 feet long, or two hanging cylindrical feeders
with shallow pans. Feed also may be placed in
shallow pans or cardboard egg flats for the first 2 or 3
days. When the chicks are 2 weeks old, change to
medium-size feeders, using two 4-foot feeders, or four
hanging feeders. After the birds are 12 weeks old,
provide one 4-foot feeder or one hanging feeder for
each 25 birds. Adequate feeder space is important to
prevent stress and to allow chicks to grow properly.

Avoid feed wastage. Feeders need to be full
during the first day or two of the chick's life so that the
chicks can easily find the feed. From then on, feeders
should be filled from one-half to two-thirds full.
Avoiding feed wastage will reduce feed cost. About 20
pounds of feed (starter and grower) are required to
grow a pullet from 1 day to 5 months old, or about the
time the pullet should start laying.

Under ideal conditions, broilers can be grown on
2 pounds or less of feed for each pound of body weight.

Watering

A plentiful supply of cool, clean drinking water is
one of the most important requirements in raising
chicks and the least expensive. Be sure your chicks
have adequate water all day long, every day. One
hundred chicks will need two 1-gallon waterers. Place
the waterers on a short piece of board (1" x 10" x10")
to help keep litter out of the water and thus keep the
water clean. The waterer should be kept level to
prevent leakage and wet litter.


When chicks are about 4 weeks old, change to
larger waterers. Two 3-gallon double-wall waters,
or one automatic waterer will supply the chicks daily
needforwater. These samelargeorautomaticwaterer
can be used during the growing and laying period.
Clean the waterers daily and keep them in a shaded
location. Always have a minimum of two waterers
available to the chicks in case of failure of one.

For broilers, change to four larger waterers per
100 chicks at 2 weeks of age.

Some Helpful Hints

Watch the chicks closely the first day and nightto
see that they are comfortable. Theyshouldbeprovided
with a warm, dry place with feed and water that is
easily found.

Don't fill the feed troughs too fall after the first 2
days or the chicks will scratch the feed outandwasteiL

Stir and keep litter dry. Remove anyJitter that
becomes wet. Wet litter is an excellent, place fEr
disease organisms and parasites to grow.

After the first week, increase the amoMnt ofairin
the brooder house to allow for good ventilation.

Watch for coccidiosis in the chicks. This disease
generally affects chicks between 2 and 10 weeks of
age. Symptoms include bloody droppings, ruffled
feathers, drooped wings and the chick i usuallypals,
cold and listless. To control the disease, use starter
and grower feeds that contain a coccidiostat

Cannibalism (birds pecking one another until
blood shows) can become a problem if birds become
overheated, overcrowded, orundrfed. Provideplenty
of fresh air and increase floor space to 2-3 square feet
per bird as chicks grow. Trim the chicks' beaks to
prevent cannibalism. Using stop-picksalves willhlp
control cannibalism.

Separate cockerels from the pullets (in egg-type
breeds) when 6 to 8 weeks ofage. When the cockerels
weigh about 3 pounds each, they should be sold or
slaughtered.

Vaccinate egg-type birds against fowl pox when
they are 6 to 9 weeks old. Vaccination is simple and
inexpensive. Follow directions on the vaccine


Page 9






Circular 813


container. The vaccine can usually be obtained from
feed dealers.

Keep chicks and growing pullets away from older
chickens and other species of poultry at all times to
avoid exposure to disease. Birds exhibited with other
poultry (e.g., at fairs) should not be returned to the
flock because of possible disease exposure. Breeders
ofexhibition stock need to have an isolation/quarantine
pen in which to hold exhibited birds for about 4 weeks
before returning them to the flock.

Layer House

For the small flock, layer houses should not be
elaborate or expensive. The house only needs to
consist of an area covered by a roof (to keep out the hot
sun and rain) and enclosed by wire to confine the
layers and exclude predators. A solid wall on the
windward side is helpful to keep out blowing rains
and cold, winter winds. The wall can be wood, metal
or plastic and can be either permanent or removable.
Earth floors covered with 4 to 6 inches of litter are
preferred.-i Roost poles are optional, but the birds
usually like to use them. Provide one nest for every
four hens. Have nests available to pullets before 20
weeks of age.

DISPLAYING LIVING CHICKEN EMBRYOS

Live minbryos make an interesting exhibit for
fairs or science exhibitions if properly presented. In
preparation for the display, the student must arrange
his setting schedule so that all of the embryos to be
displayed will be the proper age on the day of the
show. It is suggested that 3, 5, 7 and 10 days would
be appropriate ages of embryos for display.
Approximately 6 eggs should be set for every age of
embryo to be displayed. This allows for infertility,
poor technique, and embryonic mortality. It also
provides extra embryos in case some should dry out
too much during display. To determine setting time,
count back the number days of age for each embryo
from the date it is to be displayed. Two to 3 hours
should be allowed for warm-up of eggs in determining
setting time.


Materials and Supplies

Incubator
Incubated fertile eggs
Forceps (tweezers)
Small scissors
Eye dropper
Egg carton (to hold eggs) or an elevated
pedestal for each age of embryo, to be placed
near the glass top of your incubator. Pedestal
can be a wooden block, 0.75" x 2" x 2", with a
1 to 1.25" hole.
Small, soft artist's brush
Petroleum jelly
Distilled or soft water

Procedures

All instruments that will penetrate the egg
(scissors, tweezers, etc.) should be placed in boiling
water for 30 minutes and then dipped in alcohol for
sterilization.

To prepare for the removal of the shell, candle the
egg and mark the outline of the air cell. Using a knife
or scissors, carefully punch a small hole in the center
of the air cell outline. If a chandler is not available and
you do not wish to construct one, a small hole may be
punched in the center of the large end of the egg.
Proceeding carefully, enlarge the hole, taking care
not to rupture the inner shell membrane. The shell
and outer shell membrane should be removed to the
very edge of thejunct ion of the shell, air cell and inner
shell membrane. Visibility is greatly reduced by the
inner shell membrane. This membrane can be
removed, but some skill is necessary to do so without
rupturing the blood vessels of the underlying
embryonic membrane chorioallantoiss).

At this point you may proceed with either of two
methods. One method is to place a drop of distilled or
soft water on the membrane near the edge of the shell.
Grasp the membrane with the tweezers gently at its
junction with the shell, being careful not to grasp any
blood vessels or albumen. Now, very gently and very
slowly, pull the membrane away from the shell, blood
vessels and albumen (the use of a second pair of
tweezers may be valuable here). The membrane
should be completely removed to the size of the shell
opening.


Page 10






Circular 813


container. The vaccine can usually be obtained from
feed dealers.

Keep chicks and growing pullets away from older
chickens and other species of poultry at all times to
avoid exposure to disease. Birds exhibited with other
poultry (e.g., at fairs) should not be returned to the
flock because of possible disease exposure. Breeders
ofexhibition stock need to have an isolation/quarantine
pen in which to hold exhibited birds for about 4 weeks
before returning them to the flock.

Layer House

For the small flock, layer houses should not be
elaborate or expensive. The house only needs to
consist of an area covered by a roof (to keep out the hot
sun and rain) and enclosed by wire to confine the
layers and exclude predators. A solid wall on the
windward side is helpful to keep out blowing rains
and cold, winter winds. The wall can be wood, metal
or plastic and can be either permanent or removable.
Earth floors covered with 4 to 6 inches of litter are
preferred.-i Roost poles are optional, but the birds
usually like to use them. Provide one nest for every
four hens. Have nests available to pullets before 20
weeks of age.

DISPLAYING LIVING CHICKEN EMBRYOS

Live minbryos make an interesting exhibit for
fairs or science exhibitions if properly presented. In
preparation for the display, the student must arrange
his setting schedule so that all of the embryos to be
displayed will be the proper age on the day of the
show. It is suggested that 3, 5, 7 and 10 days would
be appropriate ages of embryos for display.
Approximately 6 eggs should be set for every age of
embryo to be displayed. This allows for infertility,
poor technique, and embryonic mortality. It also
provides extra embryos in case some should dry out
too much during display. To determine setting time,
count back the number days of age for each embryo
from the date it is to be displayed. Two to 3 hours
should be allowed for warm-up of eggs in determining
setting time.


Materials and Supplies

Incubator
Incubated fertile eggs
Forceps (tweezers)
Small scissors
Eye dropper
Egg carton (to hold eggs) or an elevated
pedestal for each age of embryo, to be placed
near the glass top of your incubator. Pedestal
can be a wooden block, 0.75" x 2" x 2", with a
1 to 1.25" hole.
Small, soft artist's brush
Petroleum jelly
Distilled or soft water

Procedures

All instruments that will penetrate the egg
(scissors, tweezers, etc.) should be placed in boiling
water for 30 minutes and then dipped in alcohol for
sterilization.

To prepare for the removal of the shell, candle the
egg and mark the outline of the air cell. Using a knife
or scissors, carefully punch a small hole in the center
of the air cell outline. If a chandler is not available and
you do not wish to construct one, a small hole may be
punched in the center of the large end of the egg.
Proceeding carefully, enlarge the hole, taking care
not to rupture the inner shell membrane. The shell
and outer shell membrane should be removed to the
very edge of thejunct ion of the shell, air cell and inner
shell membrane. Visibility is greatly reduced by the
inner shell membrane. This membrane can be
removed, but some skill is necessary to do so without
rupturing the blood vessels of the underlying
embryonic membrane chorioallantoiss).

At this point you may proceed with either of two
methods. One method is to place a drop of distilled or
soft water on the membrane near the edge of the shell.
Grasp the membrane with the tweezers gently at its
junction with the shell, being careful not to grasp any
blood vessels or albumen. Now, very gently and very
slowly, pull the membrane away from the shell, blood
vessels and albumen (the use of a second pair of
tweezers may be valuable here). The membrane
should be completely removed to the size of the shell
opening.


Page 10






Circular 813


container. The vaccine can usually be obtained from
feed dealers.

Keep chicks and growing pullets away from older
chickens and other species of poultry at all times to
avoid exposure to disease. Birds exhibited with other
poultry (e.g., at fairs) should not be returned to the
flock because of possible disease exposure. Breeders
ofexhibition stock need to have an isolation/quarantine
pen in which to hold exhibited birds for about 4 weeks
before returning them to the flock.

Layer House

For the small flock, layer houses should not be
elaborate or expensive. The house only needs to
consist of an area covered by a roof (to keep out the hot
sun and rain) and enclosed by wire to confine the
layers and exclude predators. A solid wall on the
windward side is helpful to keep out blowing rains
and cold, winter winds. The wall can be wood, metal
or plastic and can be either permanent or removable.
Earth floors covered with 4 to 6 inches of litter are
preferred.-i Roost poles are optional, but the birds
usually like to use them. Provide one nest for every
four hens. Have nests available to pullets before 20
weeks of age.

DISPLAYING LIVING CHICKEN EMBRYOS

Live minbryos make an interesting exhibit for
fairs or science exhibitions if properly presented. In
preparation for the display, the student must arrange
his setting schedule so that all of the embryos to be
displayed will be the proper age on the day of the
show. It is suggested that 3, 5, 7 and 10 days would
be appropriate ages of embryos for display.
Approximately 6 eggs should be set for every age of
embryo to be displayed. This allows for infertility,
poor technique, and embryonic mortality. It also
provides extra embryos in case some should dry out
too much during display. To determine setting time,
count back the number days of age for each embryo
from the date it is to be displayed. Two to 3 hours
should be allowed for warm-up of eggs in determining
setting time.


Materials and Supplies

Incubator
Incubated fertile eggs
Forceps (tweezers)
Small scissors
Eye dropper
Egg carton (to hold eggs) or an elevated
pedestal for each age of embryo, to be placed
near the glass top of your incubator. Pedestal
can be a wooden block, 0.75" x 2" x 2", with a
1 to 1.25" hole.
Small, soft artist's brush
Petroleum jelly
Distilled or soft water

Procedures

All instruments that will penetrate the egg
(scissors, tweezers, etc.) should be placed in boiling
water for 30 minutes and then dipped in alcohol for
sterilization.

To prepare for the removal of the shell, candle the
egg and mark the outline of the air cell. Using a knife
or scissors, carefully punch a small hole in the center
of the air cell outline. If a chandler is not available and
you do not wish to construct one, a small hole may be
punched in the center of the large end of the egg.
Proceeding carefully, enlarge the hole, taking care
not to rupture the inner shell membrane. The shell
and outer shell membrane should be removed to the
very edge of thejunct ion of the shell, air cell and inner
shell membrane. Visibility is greatly reduced by the
inner shell membrane. This membrane can be
removed, but some skill is necessary to do so without
rupturing the blood vessels of the underlying
embryonic membrane chorioallantoiss).

At this point you may proceed with either of two
methods. One method is to place a drop of distilled or
soft water on the membrane near the edge of the shell.
Grasp the membrane with the tweezers gently at its
junction with the shell, being careful not to grasp any
blood vessels or albumen. Now, very gently and very
slowly, pull the membrane away from the shell, blood
vessels and albumen (the use of a second pair of
tweezers may be valuable here). The membrane
should be completely removed to the size of the shell
opening.


Page 10






Circular 813


container. The vaccine can usually be obtained from
feed dealers.

Keep chicks and growing pullets away from older
chickens and other species of poultry at all times to
avoid exposure to disease. Birds exhibited with other
poultry (e.g., at fairs) should not be returned to the
flock because of possible disease exposure. Breeders
ofexhibition stock need to have an isolation/quarantine
pen in which to hold exhibited birds for about 4 weeks
before returning them to the flock.

Layer House

For the small flock, layer houses should not be
elaborate or expensive. The house only needs to
consist of an area covered by a roof (to keep out the hot
sun and rain) and enclosed by wire to confine the
layers and exclude predators. A solid wall on the
windward side is helpful to keep out blowing rains
and cold, winter winds. The wall can be wood, metal
or plastic and can be either permanent or removable.
Earth floors covered with 4 to 6 inches of litter are
preferred.-i Roost poles are optional, but the birds
usually like to use them. Provide one nest for every
four hens. Have nests available to pullets before 20
weeks of age.

DISPLAYING LIVING CHICKEN EMBRYOS

Live minbryos make an interesting exhibit for
fairs or science exhibitions if properly presented. In
preparation for the display, the student must arrange
his setting schedule so that all of the embryos to be
displayed will be the proper age on the day of the
show. It is suggested that 3, 5, 7 and 10 days would
be appropriate ages of embryos for display.
Approximately 6 eggs should be set for every age of
embryo to be displayed. This allows for infertility,
poor technique, and embryonic mortality. It also
provides extra embryos in case some should dry out
too much during display. To determine setting time,
count back the number days of age for each embryo
from the date it is to be displayed. Two to 3 hours
should be allowed for warm-up of eggs in determining
setting time.


Materials and Supplies

Incubator
Incubated fertile eggs
Forceps (tweezers)
Small scissors
Eye dropper
Egg carton (to hold eggs) or an elevated
pedestal for each age of embryo, to be placed
near the glass top of your incubator. Pedestal
can be a wooden block, 0.75" x 2" x 2", with a
1 to 1.25" hole.
Small, soft artist's brush
Petroleum jelly
Distilled or soft water

Procedures

All instruments that will penetrate the egg
(scissors, tweezers, etc.) should be placed in boiling
water for 30 minutes and then dipped in alcohol for
sterilization.

To prepare for the removal of the shell, candle the
egg and mark the outline of the air cell. Using a knife
or scissors, carefully punch a small hole in the center
of the air cell outline. If a chandler is not available and
you do not wish to construct one, a small hole may be
punched in the center of the large end of the egg.
Proceeding carefully, enlarge the hole, taking care
not to rupture the inner shell membrane. The shell
and outer shell membrane should be removed to the
very edge of thejunct ion of the shell, air cell and inner
shell membrane. Visibility is greatly reduced by the
inner shell membrane. This membrane can be
removed, but some skill is necessary to do so without
rupturing the blood vessels of the underlying
embryonic membrane chorioallantoiss).

At this point you may proceed with either of two
methods. One method is to place a drop of distilled or
soft water on the membrane near the edge of the shell.
Grasp the membrane with the tweezers gently at its
junction with the shell, being careful not to grasp any
blood vessels or albumen. Now, very gently and very
slowly, pull the membrane away from the shell, blood
vessels and albumen (the use of a second pair of
tweezers may be valuable here). The membrane
should be completely removed to the size of the shell
opening.


Page 10






Ck~rciW14


The disadvantage of this method is that eggs
prepared this way tend to dry out more rapidly which
results in the death of the embryo; however, the
embryos will remain in good condition (in the
incubator) for several hours, which is generally long
enough for the period of display. It should be pointed
out that the removal of the inner shell membrane
should be delayed as long as possible. The ideal
situation is to remove the membrane immediately
before the exhibition begins.

If the first method proves to be undesirable, a
second method is to brush the inner membrane with
petroleum jelly. This method helps to retard
evaporation. At incubation temperature, petroleum
jelly melts and makes the membrane relatively
transparent. Visibility is not as good as with the
peeling method but until some skill is attained, the
petroleum jelly method is more likely to be successful.

It is possible that specimens could dry out during
prolonged display; this should cause no problems
because extra eggs have been set for every embryo age
and all that is necessary is to open a new embryo ofthe
proper age.

THE PREPARATION AND PRESERVATION
OF EMBRYOS

Chick embryo displays are popular and
educational in many situations. The great changes in
size and form that take place from day to day are quite
startling. It is possible to preserve embryos so that
they maintain their original size and shape for several
years. The natural color of the embryo is bleached
away by the preparation, but this does not detract too
much from the display because the size and shape of
the embryo are the most striking aspects of the
exhibit. The preservant used is made by mixing 1 part
(by volume) of formalin (37.5 or 40% formaldehyde)
with 3 parts (by volume) of water. Embryos of various
ages are freed of yolk, albumen, and extra-embryonic
membranes and placed in the formaldehyde solution
for fixing and preserving. The solution should be
changed twice, or as required for it to remain clear.


Materials and Supplies

Incubator
Incubated fertile eggs
Egg chandler (optional)
Pencil
Small scissors
Forceps (tweezers)
Formalin (37.5 or 40% formaldehyde) Cautin,
avoid excessive inhalation and skin contact of
formalin
Water (soft or distilled)
Salt (NaCI)
2 or more bowls or petri dishes
Jars (baby food or similar size)

Procedures

The student should allow for infertile eggs,
embryonic mortality and accidents by setting atleast
three eggs for each embryo wanted for preservation.
The setting schedule can be arranged so that the
embryos of the desired age come off on a convenient
day. Count back the number of days of age for each
embryo from the date the embryo is to be prepared
and this is the setting date. Embryos canbeprepared
conveniently from 4 to 19 days ofagetogivepractically
a complete observable record of chick development
from fertilization to hatching at 21 days. It would be
an advantage to start with the older embryos and
proceedbackward. Thisway,techniqueandIfaname
would improve as the embryos become more fragile.

To prepare the embryo from the incubated egg,
crack the shell as if to fry an egg. This should be done
over a sink. Let the contents of the egg drop gently
into a dish or plate. Carefully rupture the embryonic
membrane (amnion) surrounding the embryo and
gently pick up the embryo by slipping the fingers,
forceps, ora spoon underneathitforsupport. Transfer
the embryo to a bowl which contains saline solution (9
grams non-iodized table salt in 1,000 ml of water).
Here the embryo is gently swished around in the
solution to free it of undesirable materiaL The
structure (umbilical) attached to the abdomen must
be clipped to remove the embryonic membranes
Transfer the embryo to another bowl combing the
formaldehyde solution and allow to stand for several
minutes. Now fill a clear jar (baby food size) with the
diluted formalin solution (3 parts water to 1 part
formalin) and drop in the embryo. Do not be alarmed
if the embryo floats as this is normal until its tissues


Page 11






Ck~rciW14


The disadvantage of this method is that eggs
prepared this way tend to dry out more rapidly which
results in the death of the embryo; however, the
embryos will remain in good condition (in the
incubator) for several hours, which is generally long
enough for the period of display. It should be pointed
out that the removal of the inner shell membrane
should be delayed as long as possible. The ideal
situation is to remove the membrane immediately
before the exhibition begins.

If the first method proves to be undesirable, a
second method is to brush the inner membrane with
petroleum jelly. This method helps to retard
evaporation. At incubation temperature, petroleum
jelly melts and makes the membrane relatively
transparent. Visibility is not as good as with the
peeling method but until some skill is attained, the
petroleum jelly method is more likely to be successful.

It is possible that specimens could dry out during
prolonged display; this should cause no problems
because extra eggs have been set for every embryo age
and all that is necessary is to open a new embryo ofthe
proper age.

THE PREPARATION AND PRESERVATION
OF EMBRYOS

Chick embryo displays are popular and
educational in many situations. The great changes in
size and form that take place from day to day are quite
startling. It is possible to preserve embryos so that
they maintain their original size and shape for several
years. The natural color of the embryo is bleached
away by the preparation, but this does not detract too
much from the display because the size and shape of
the embryo are the most striking aspects of the
exhibit. The preservant used is made by mixing 1 part
(by volume) of formalin (37.5 or 40% formaldehyde)
with 3 parts (by volume) of water. Embryos of various
ages are freed of yolk, albumen, and extra-embryonic
membranes and placed in the formaldehyde solution
for fixing and preserving. The solution should be
changed twice, or as required for it to remain clear.


Materials and Supplies

Incubator
Incubated fertile eggs
Egg chandler (optional)
Pencil
Small scissors
Forceps (tweezers)
Formalin (37.5 or 40% formaldehyde) Cautin,
avoid excessive inhalation and skin contact of
formalin
Water (soft or distilled)
Salt (NaCI)
2 or more bowls or petri dishes
Jars (baby food or similar size)

Procedures

The student should allow for infertile eggs,
embryonic mortality and accidents by setting atleast
three eggs for each embryo wanted for preservation.
The setting schedule can be arranged so that the
embryos of the desired age come off on a convenient
day. Count back the number of days of age for each
embryo from the date the embryo is to be prepared
and this is the setting date. Embryos canbeprepared
conveniently from 4 to 19 days ofagetogivepractically
a complete observable record of chick development
from fertilization to hatching at 21 days. It would be
an advantage to start with the older embryos and
proceedbackward. Thisway,techniqueandIfaname
would improve as the embryos become more fragile.

To prepare the embryo from the incubated egg,
crack the shell as if to fry an egg. This should be done
over a sink. Let the contents of the egg drop gently
into a dish or plate. Carefully rupture the embryonic
membrane (amnion) surrounding the embryo and
gently pick up the embryo by slipping the fingers,
forceps, ora spoon underneathitforsupport. Transfer
the embryo to a bowl which contains saline solution (9
grams non-iodized table salt in 1,000 ml of water).
Here the embryo is gently swished around in the
solution to free it of undesirable materiaL The
structure (umbilical) attached to the abdomen must
be clipped to remove the embryonic membranes
Transfer the embryo to another bowl combing the
formaldehyde solution and allow to stand for several
minutes. Now fill a clear jar (baby food size) with the
diluted formalin solution (3 parts water to 1 part
formalin) and drop in the embryo. Do not be alarmed
if the embryo floats as this is normal until its tissues


Page 11






Ck~rciW14


The disadvantage of this method is that eggs
prepared this way tend to dry out more rapidly which
results in the death of the embryo; however, the
embryos will remain in good condition (in the
incubator) for several hours, which is generally long
enough for the period of display. It should be pointed
out that the removal of the inner shell membrane
should be delayed as long as possible. The ideal
situation is to remove the membrane immediately
before the exhibition begins.

If the first method proves to be undesirable, a
second method is to brush the inner membrane with
petroleum jelly. This method helps to retard
evaporation. At incubation temperature, petroleum
jelly melts and makes the membrane relatively
transparent. Visibility is not as good as with the
peeling method but until some skill is attained, the
petroleum jelly method is more likely to be successful.

It is possible that specimens could dry out during
prolonged display; this should cause no problems
because extra eggs have been set for every embryo age
and all that is necessary is to open a new embryo ofthe
proper age.

THE PREPARATION AND PRESERVATION
OF EMBRYOS

Chick embryo displays are popular and
educational in many situations. The great changes in
size and form that take place from day to day are quite
startling. It is possible to preserve embryos so that
they maintain their original size and shape for several
years. The natural color of the embryo is bleached
away by the preparation, but this does not detract too
much from the display because the size and shape of
the embryo are the most striking aspects of the
exhibit. The preservant used is made by mixing 1 part
(by volume) of formalin (37.5 or 40% formaldehyde)
with 3 parts (by volume) of water. Embryos of various
ages are freed of yolk, albumen, and extra-embryonic
membranes and placed in the formaldehyde solution
for fixing and preserving. The solution should be
changed twice, or as required for it to remain clear.


Materials and Supplies

Incubator
Incubated fertile eggs
Egg chandler (optional)
Pencil
Small scissors
Forceps (tweezers)
Formalin (37.5 or 40% formaldehyde) Cautin,
avoid excessive inhalation and skin contact of
formalin
Water (soft or distilled)
Salt (NaCI)
2 or more bowls or petri dishes
Jars (baby food or similar size)

Procedures

The student should allow for infertile eggs,
embryonic mortality and accidents by setting atleast
three eggs for each embryo wanted for preservation.
The setting schedule can be arranged so that the
embryos of the desired age come off on a convenient
day. Count back the number of days of age for each
embryo from the date the embryo is to be prepared
and this is the setting date. Embryos canbeprepared
conveniently from 4 to 19 days ofagetogivepractically
a complete observable record of chick development
from fertilization to hatching at 21 days. It would be
an advantage to start with the older embryos and
proceedbackward. Thisway,techniqueandIfaname
would improve as the embryos become more fragile.

To prepare the embryo from the incubated egg,
crack the shell as if to fry an egg. This should be done
over a sink. Let the contents of the egg drop gently
into a dish or plate. Carefully rupture the embryonic
membrane (amnion) surrounding the embryo and
gently pick up the embryo by slipping the fingers,
forceps, ora spoon underneathitforsupport. Transfer
the embryo to a bowl which contains saline solution (9
grams non-iodized table salt in 1,000 ml of water).
Here the embryo is gently swished around in the
solution to free it of undesirable materiaL The
structure (umbilical) attached to the abdomen must
be clipped to remove the embryonic membranes
Transfer the embryo to another bowl combing the
formaldehyde solution and allow to stand for several
minutes. Now fill a clear jar (baby food size) with the
diluted formalin solution (3 parts water to 1 part
formalin) and drop in the embryo. Do not be alarmed
if the embryo floats as this is normal until its tissues


Page 11







Circular 813


0
I DAY
(00002 6RAM)





8 DAYS
(1.15 GRAMS)




15 DAYS
(12.00 GRAMS)


2 DAYS
(0.003 GRAM)





9 DAYS
(1.53 GRAMS)




16 DAYS
(Iee GRAMs)


3 DAYS
(002 GRAM)





10 DAYS
(2.26 GRAMS)




17 DNS
(1se.9 teams)


4 DAYS
(005 GRAM)





II DAYS
(3.68 GRAMS)




18 DAYS
(21.3 IGAMS)


5 DAYS 6 DAYS 7 DAYS
(013 GRAM) a.29 GRAM) (057 GRAM)





12 DAYS 13 DAYS 14 DAYS
(5.07 GRAMS) (737 GRAMS) (74 GRAMS)


!S 20 DAYS 21 DAYS
AS) (l021 GRAMS) (HATCHED)


Figure 3.
Daily changes in the weight and the form of the developing chick embryo.
(Adapted from Romanoff, Cornell Rural Science leaflet, Sept. 1939)


absorb some of the solution. Check the
preserved specimens at intervals and
transfer them to a fresh diluted formalin
solution if the solution is cloudy or
contains floating tissue, etc. Continue
these transfers until the solution
remains clear and free of extraneous
floating tissue. When this point is
reached, fill the jars to the top and close
them tightly. Never leave the embryo
exposed to air for any extended period.
Label the embryo indicating species,
age and other pertinent data. To leave
an unobstructed view of the specimen,
place the label on the top of the cap.

Listed below are some of the changes
that take place during embryonic
development (also see Figure 3). It
usually enhances the exhibit to include
descriptions that apply to the embryonic
ages that are displayed.


LANDMARKS OF EMBRYONIC DEVELOPMENT

Before the Egg is Laid (Pre-Oviposition):

Ovulation (in ovary) First meiotic division of oogenesis.
30 min. post-ovulation (in infundibulum) Second meiotic division and fertilization.
4 h post-ovulation (in isthmus) First embryonic division.
4.3 h post-ovulation (in isthmus) Second embryonic division.
5.5 h post-ovulation (in shell gland) Third division.
6.3 h post-ovulation (in shell gland) Fourth division.
6.4 to about 25.5 h post-ovulation (egg laid) (in shell gland) Continued division and growth;
cells segregate into groups for special functions. Several hundred cells when egg is laid.
Between oviposition and incubation (during egg storage) No growth; embryo is inactive (if
embryo is held below 76F (25.5C) which is physiological zero); normal storage temperature
is 55 to 650F (13 to 180C).

During Incubation:


Day 1 -
6-10 h -
8h-
10 h-


18 h -
20 h -
21 h-
22 h -
23-24 h-


First kidney-like cells begin (pronephros).
Appearance of primitive streak.
Begin yolk sac (embryonic membrane) growth. Functions are: a) blood
formation; b) digest yolk; c) absorb yolk; d) reserve food after hatch. Mesoderm appears; embryo
oriented 900 angle to egg long axis; begin mesonephros.
Begin primitive gut; primordial germ cells appear in germinal crescent.
Begin vertebral column.
Appearance of neural groove, nervous system.
Appearance of first pair of somites (block-like segments) and head.
Begin blood islands, vitelline (yolk sac) circulation, blood, heart, blood vessels (2-4 somites).


Page 12







Circular 813


0
I DAY
(00002 6RAM)





8 DAYS
(1.15 GRAMS)




15 DAYS
(12.00 GRAMS)


2 DAYS
(0.003 GRAM)





9 DAYS
(1.53 GRAMS)




16 DAYS
(Iee GRAMs)


3 DAYS
(002 GRAM)





10 DAYS
(2.26 GRAMS)




17 DNS
(1se.9 teams)


4 DAYS
(005 GRAM)





II DAYS
(3.68 GRAMS)




18 DAYS
(21.3 IGAMS)


5 DAYS 6 DAYS 7 DAYS
(013 GRAM) a.29 GRAM) (057 GRAM)





12 DAYS 13 DAYS 14 DAYS
(5.07 GRAMS) (737 GRAMS) (74 GRAMS)


!S 20 DAYS 21 DAYS
AS) (l021 GRAMS) (HATCHED)


Figure 3.
Daily changes in the weight and the form of the developing chick embryo.
(Adapted from Romanoff, Cornell Rural Science leaflet, Sept. 1939)


absorb some of the solution. Check the
preserved specimens at intervals and
transfer them to a fresh diluted formalin
solution if the solution is cloudy or
contains floating tissue, etc. Continue
these transfers until the solution
remains clear and free of extraneous
floating tissue. When this point is
reached, fill the jars to the top and close
them tightly. Never leave the embryo
exposed to air for any extended period.
Label the embryo indicating species,
age and other pertinent data. To leave
an unobstructed view of the specimen,
place the label on the top of the cap.

Listed below are some of the changes
that take place during embryonic
development (also see Figure 3). It
usually enhances the exhibit to include
descriptions that apply to the embryonic
ages that are displayed.


LANDMARKS OF EMBRYONIC DEVELOPMENT

Before the Egg is Laid (Pre-Oviposition):

Ovulation (in ovary) First meiotic division of oogenesis.
30 min. post-ovulation (in infundibulum) Second meiotic division and fertilization.
4 h post-ovulation (in isthmus) First embryonic division.
4.3 h post-ovulation (in isthmus) Second embryonic division.
5.5 h post-ovulation (in shell gland) Third division.
6.3 h post-ovulation (in shell gland) Fourth division.
6.4 to about 25.5 h post-ovulation (egg laid) (in shell gland) Continued division and growth;
cells segregate into groups for special functions. Several hundred cells when egg is laid.
Between oviposition and incubation (during egg storage) No growth; embryo is inactive (if
embryo is held below 76F (25.5C) which is physiological zero); normal storage temperature
is 55 to 650F (13 to 180C).

During Incubation:


Day 1 -
6-10 h -
8h-
10 h-


18 h -
20 h -
21 h-
22 h -
23-24 h-


First kidney-like cells begin (pronephros).
Appearance of primitive streak.
Begin yolk sac (embryonic membrane) growth. Functions are: a) blood
formation; b) digest yolk; c) absorb yolk; d) reserve food after hatch. Mesoderm appears; embryo
oriented 900 angle to egg long axis; begin mesonephros.
Begin primitive gut; primordial germ cells appear in germinal crescent.
Begin vertebral column.
Appearance of neural groove, nervous system.
Appearance of first pair of somites (block-like segments) and head.
Begin blood islands, vitelline (yolk sac) circulation, blood, heart, blood vessels (2-4 somites).


Page 12







Circular 813


0
I DAY
(00002 6RAM)





8 DAYS
(1.15 GRAMS)




15 DAYS
(12.00 GRAMS)


2 DAYS
(0.003 GRAM)





9 DAYS
(1.53 GRAMS)




16 DAYS
(Iee GRAMs)


3 DAYS
(002 GRAM)





10 DAYS
(2.26 GRAMS)




17 DNS
(1se.9 teams)


4 DAYS
(005 GRAM)





II DAYS
(3.68 GRAMS)




18 DAYS
(21.3 IGAMS)


5 DAYS 6 DAYS 7 DAYS
(013 GRAM) a.29 GRAM) (057 GRAM)





12 DAYS 13 DAYS 14 DAYS
(5.07 GRAMS) (737 GRAMS) (74 GRAMS)


!S 20 DAYS 21 DAYS
AS) (l021 GRAMS) (HATCHED)


Figure 3.
Daily changes in the weight and the form of the developing chick embryo.
(Adapted from Romanoff, Cornell Rural Science leaflet, Sept. 1939)


absorb some of the solution. Check the
preserved specimens at intervals and
transfer them to a fresh diluted formalin
solution if the solution is cloudy or
contains floating tissue, etc. Continue
these transfers until the solution
remains clear and free of extraneous
floating tissue. When this point is
reached, fill the jars to the top and close
them tightly. Never leave the embryo
exposed to air for any extended period.
Label the embryo indicating species,
age and other pertinent data. To leave
an unobstructed view of the specimen,
place the label on the top of the cap.

Listed below are some of the changes
that take place during embryonic
development (also see Figure 3). It
usually enhances the exhibit to include
descriptions that apply to the embryonic
ages that are displayed.


LANDMARKS OF EMBRYONIC DEVELOPMENT

Before the Egg is Laid (Pre-Oviposition):

Ovulation (in ovary) First meiotic division of oogenesis.
30 min. post-ovulation (in infundibulum) Second meiotic division and fertilization.
4 h post-ovulation (in isthmus) First embryonic division.
4.3 h post-ovulation (in isthmus) Second embryonic division.
5.5 h post-ovulation (in shell gland) Third division.
6.3 h post-ovulation (in shell gland) Fourth division.
6.4 to about 25.5 h post-ovulation (egg laid) (in shell gland) Continued division and growth;
cells segregate into groups for special functions. Several hundred cells when egg is laid.
Between oviposition and incubation (during egg storage) No growth; embryo is inactive (if
embryo is held below 76F (25.5C) which is physiological zero); normal storage temperature
is 55 to 650F (13 to 180C).

During Incubation:


Day 1 -
6-10 h -
8h-
10 h-


18 h -
20 h -
21 h-
22 h -
23-24 h-


First kidney-like cells begin (pronephros).
Appearance of primitive streak.
Begin yolk sac (embryonic membrane) growth. Functions are: a) blood
formation; b) digest yolk; c) absorb yolk; d) reserve food after hatch. Mesoderm appears; embryo
oriented 900 angle to egg long axis; begin mesonephros.
Begin primitive gut; primordial germ cells appear in germinal crescent.
Begin vertebral column.
Appearance of neural groove, nervous system.
Appearance of first pair of somites (block-like segments) and head.
Begin blood islands, vitelline (yolk sac) circulation, blood, heart, blood vessels (2-4 somites).


Page 12







Circular 813


Day 2 -
25 h Appearance of eye; vertebral column visible; embryo begins to turn on left side (6 somites)
28 h Ear begins (7 somitesl.
30 h Begin amnion (embryonic membrane around embryo). Functions are: a) primarily protection of
embryo against shock and sticking; b) some albumen absorption. Begin chorion (embryonic
membrane that fuses with allantois); heartbeat begins (10 somites).
38 h Cranial flexure and torsion evident; heartbeat moves blood (16-17 somites).
42 h Thyroid begins.
48 h Anterior pituitary and pineal glands begin.

Day 3 -
50 h Embryo turns on left side; begin allantois (embryonic membrane that fuses with chorion).
Functions of chorioallantois are: a) respiration; b) absorb albumen; c) absorb calcium from shell;
d' store kidney excretions.
60 h Begin nasal pits, pharynx, lungs, anterior limb buds.
62 h Begin posterior limb buds.
72 h Begin middle and outer ear, trachea; amnion completes growth around
embryo.

Day 4 -
Begin tongue and esophagus; embryo separates from yolk sac; allantois grows through amnion;
contractions occur in amnion wall; adrenal begins; pronephros Inon-functional kidney) disappears;
metanephros Idefinitive or final-type kidney) begins; begin proventriculus, gizzard, ceca, large intestine.
Pigment visible in eye (dark eye).

Day 5 -
Appearance of reproductive system and differentiation of sex; begin thymus, bursa of Fabricius,
duodenal loop; chorion and allantois begin to fuse; mesonephros begins function; first cartilage present.

Day 6 -
Appearance of beak; voluntary movement; chorioallantois (chorion fused with allantois) lies against shell
near the large end.

Day 7 -
Digits appear; comb growth begins; egg tooth begins; melanin produced; absorption of mineral from shell
begins. Chorioallantois attached to inner shell membrane and growing around the surface.

Day 8 -
Feather tracts appear (no feathers); parathyroid begins; bone calcification begins.

Day 9 -
Growth of chorioallantois about 80% complete (still open at small end); mouth opening
appears.

Day 10 -
Beak begins to harden; digits completely separated.

Day 11 -
Abdominal walls established; loops of intestine begin protruding into the yolk sac; down
feathers visible; comb and wattles visible; claws and scales on toes; maximum function of
mesonephros, then start degeneration; metanephros starts function.


Page 13






Circular 813


Day 12 -
Chorioallantois completes enclosure of egg contents; embryo water content begins decreasing.

Day 13 -
Cartilaginous skeleton is relatively complete; embryo heat production and oxygen consumption begin to
increase rapidly.

Day 14-
Embryo begins to turn head toward large end of egg; long bone ossification becomes rapid. Turning of
egg no longer essential.

Day 15-
Intestinal loops easily seen in yolk sac; contraction of amnion ceases.

Day 16-
Beak. claws, and scales relatively cornified; albumen is practically gone and yolk increasingly important
as food source; down feathers cover body; begin retraction of intestinal loops into body.

Day 17 -
Amniotic fluid decreases; embryo positioning head toward large end, toward right wing with beak
toward air cell; definitive feathers begin.

Day 18-
Blood volume decreases, total blood hemoglobin decreases. Should complete move into the proper
position to hatch, i.e., embryo long axis the same as long axis of egg, head in large end of egg,
head to right and under right wing, beak pointed toward air cell, and feet toward head.
Transfer eggs to.hatching trays in a separate incubator (if used).

Day 19 -
Intestinal loop retraction complete; yolk sac begins to enter body cavity; amniotic fluid disappears
(swallowed by embryo); beak may pierce air cell and lungs begin some functioning (pulmonary
respiration).

Day 20 -
Yolk sac completely drawn into body; air cell pierced, followed by functioning of pulmonary respiration;
embryo makes sounds; chorioallantoic circulation, respiration and absorption decreases; may pip shell.

Day 21 -
Hatching process: chorioallantoic circulation ceases; breaks shell over air cell with egg tooth; embryo
slowly rotates in egg counterclockwise, chipping and breaking shell as it rotates; embryo kicks and
attempts to straighten neck, pushes shell open; kicks free of shell, rests, straightens, dries.

After Day 21 -
Some embryos are unable to hatch but survive beyond the normal hatching time.

Developmental stages of other avian species can be estimated by comparing with those of the chicken on
a "percentage of incubation time" basis.

After the chick hatches it should be left in the hatcher (or incubator) for 4 hours, or until it is dry and fluffed.
The navel should be well-healed and the chick walking about with a strong and steady gait. Place chick in a
brooder with a temperature of 95F (35C) with plenty of feed and water available (see section on chick care).


Page 14






Ciaular813


PREPARATION AND DEMONSTRATION OF
VARIOUS ANATOMICAL SYSTEMS OF FOWL

Preparation of a Skeleton for Exhibition

The skeletal structure of the bird is designed for
maneuverability, speed on the ground, and the unique
ability of flight. This requires that the skeleton to be
both strong and lightweight. Compared to other
animals, the avian skeleton usually has fewer bones,
many fused bones, higher mineral content, and
pneumatic bones (hollow with pockets of air).

A mature chicken should be used for this
preparation because fully ossified bones give the best
results.

The bird should be humanely killed (carbon dioxide
gas is humane and causes no damage to the skeleton)
and as much tissue and muscle as possible removed
from the bones. Care should be taken not to damage
the bones, especially small bones of the head and ribs.
The remaining tissue can be loosened from the bone
by cooking the skeleton in boiling water for about 3
hours. The bones should be scrubbed clean with a
small brush. Soaking the bones in chlorine bleach for
about 1 hour will whiten and further clean them.

Dermestid beetles or their larvae also may be
used to clean soft tissue remnants from bone surfaces
and holes before bleaching. Approximately 6 to 10
larvae are needed for chick skeletons and
proportionally more for larger birds. Sources of
dermestid beetles include high school biology
departments, college biology or zoology departments,
and museums.

After drying, the bones may be assembled with
wire and glue and mounted on a small rod. The
skeleton may be coated with a thin coat of varnish for
protect ion. The skeleton of a chicken is illustrated in
Figure 4.

Staining Tissues of Intact
Embryonic Specimens

Staining techniques may be used to demonstrate
various tissues and anatomical structures in intact
specimens or to show the development of an organ or
tissue at different stages of incubation. The following
procedure is for the specific staining of bone tissue.


Remove feathers or downby droppingtheembryo
into a sodium sulfide solution for a few minutes and
then washing the specimen thoroughly. For large
embryos or chicks, it may be necessary to remove the
skin from the specimen.

Fix specimen by transferring to a jar of 95%
alcohol for at least 3 days, then dehydrate with 100%
alcohol for 5 to 8 hours.

Place the embryo in acetone to extract the fat.
Several changes of acetone willbe necessarybefreall
the fat is removed. Continue changes until the fluid
remains clear.

Clear the specimen in 2% potassium hydroxide
(KOH). Change the solution until itremainselearfur
at least 2 days.

Stain the specimen by placing it in alizarin red
solution made up in potassium hydride solution.
Prepare astocksolutionoflgramalizarinred(alizarin
sodium monosulfonate) in 100 parts of water. Use 1
ml of this stock solution to 100 ml of 2% KOH.
Staining willbe complete within 12to24hours. Over-
staining may be somewhat corrected by placing the
specimen in sunlight.

Final clearing isaccompshed byinfiltratingthe
specimen with glycerin. Startwithasolutionofpart
glycerin to 4 parts KOH for 2 to 3 days. Gradually
increase glycerin until the specimen is mounted in
pure glycerin.

After the stock solutions have been prepared, it
will require 7 to 21 days for the fixing, clearing,
staining and final transfers ofeachspecimen. Several
specimens may be prepared simultaneously.

Preparation of Soft Organs
for Exhibition

Some of the hollow organs (e.g., the respiratory
system and circulatory system) maybe demontratd
by casting them (modeling true-to-life models) with
different materials. One of the most successful
materials is methyl methacrylate. A procedure for
casting organs with this material has been described
in another publication (Taylor, et aL, 1962).


Page 15






Ciaular813


PREPARATION AND DEMONSTRATION OF
VARIOUS ANATOMICAL SYSTEMS OF FOWL

Preparation of a Skeleton for Exhibition

The skeletal structure of the bird is designed for
maneuverability, speed on the ground, and the unique
ability of flight. This requires that the skeleton to be
both strong and lightweight. Compared to other
animals, the avian skeleton usually has fewer bones,
many fused bones, higher mineral content, and
pneumatic bones (hollow with pockets of air).

A mature chicken should be used for this
preparation because fully ossified bones give the best
results.

The bird should be humanely killed (carbon dioxide
gas is humane and causes no damage to the skeleton)
and as much tissue and muscle as possible removed
from the bones. Care should be taken not to damage
the bones, especially small bones of the head and ribs.
The remaining tissue can be loosened from the bone
by cooking the skeleton in boiling water for about 3
hours. The bones should be scrubbed clean with a
small brush. Soaking the bones in chlorine bleach for
about 1 hour will whiten and further clean them.

Dermestid beetles or their larvae also may be
used to clean soft tissue remnants from bone surfaces
and holes before bleaching. Approximately 6 to 10
larvae are needed for chick skeletons and
proportionally more for larger birds. Sources of
dermestid beetles include high school biology
departments, college biology or zoology departments,
and museums.

After drying, the bones may be assembled with
wire and glue and mounted on a small rod. The
skeleton may be coated with a thin coat of varnish for
protect ion. The skeleton of a chicken is illustrated in
Figure 4.

Staining Tissues of Intact
Embryonic Specimens

Staining techniques may be used to demonstrate
various tissues and anatomical structures in intact
specimens or to show the development of an organ or
tissue at different stages of incubation. The following
procedure is for the specific staining of bone tissue.


Remove feathers or downby droppingtheembryo
into a sodium sulfide solution for a few minutes and
then washing the specimen thoroughly. For large
embryos or chicks, it may be necessary to remove the
skin from the specimen.

Fix specimen by transferring to a jar of 95%
alcohol for at least 3 days, then dehydrate with 100%
alcohol for 5 to 8 hours.

Place the embryo in acetone to extract the fat.
Several changes of acetone willbe necessarybefreall
the fat is removed. Continue changes until the fluid
remains clear.

Clear the specimen in 2% potassium hydroxide
(KOH). Change the solution until itremainselearfur
at least 2 days.

Stain the specimen by placing it in alizarin red
solution made up in potassium hydride solution.
Prepare astocksolutionoflgramalizarinred(alizarin
sodium monosulfonate) in 100 parts of water. Use 1
ml of this stock solution to 100 ml of 2% KOH.
Staining willbe complete within 12to24hours. Over-
staining may be somewhat corrected by placing the
specimen in sunlight.

Final clearing isaccompshed byinfiltratingthe
specimen with glycerin. Startwithasolutionofpart
glycerin to 4 parts KOH for 2 to 3 days. Gradually
increase glycerin until the specimen is mounted in
pure glycerin.

After the stock solutions have been prepared, it
will require 7 to 21 days for the fixing, clearing,
staining and final transfers ofeachspecimen. Several
specimens may be prepared simultaneously.

Preparation of Soft Organs
for Exhibition

Some of the hollow organs (e.g., the respiratory
system and circulatory system) maybe demontratd
by casting them (modeling true-to-life models) with
different materials. One of the most successful
materials is methyl methacrylate. A procedure for
casting organs with this material has been described
in another publication (Taylor, et aL, 1962).


Page 15






Ciaular813


PREPARATION AND DEMONSTRATION OF
VARIOUS ANATOMICAL SYSTEMS OF FOWL

Preparation of a Skeleton for Exhibition

The skeletal structure of the bird is designed for
maneuverability, speed on the ground, and the unique
ability of flight. This requires that the skeleton to be
both strong and lightweight. Compared to other
animals, the avian skeleton usually has fewer bones,
many fused bones, higher mineral content, and
pneumatic bones (hollow with pockets of air).

A mature chicken should be used for this
preparation because fully ossified bones give the best
results.

The bird should be humanely killed (carbon dioxide
gas is humane and causes no damage to the skeleton)
and as much tissue and muscle as possible removed
from the bones. Care should be taken not to damage
the bones, especially small bones of the head and ribs.
The remaining tissue can be loosened from the bone
by cooking the skeleton in boiling water for about 3
hours. The bones should be scrubbed clean with a
small brush. Soaking the bones in chlorine bleach for
about 1 hour will whiten and further clean them.

Dermestid beetles or their larvae also may be
used to clean soft tissue remnants from bone surfaces
and holes before bleaching. Approximately 6 to 10
larvae are needed for chick skeletons and
proportionally more for larger birds. Sources of
dermestid beetles include high school biology
departments, college biology or zoology departments,
and museums.

After drying, the bones may be assembled with
wire and glue and mounted on a small rod. The
skeleton may be coated with a thin coat of varnish for
protect ion. The skeleton of a chicken is illustrated in
Figure 4.

Staining Tissues of Intact
Embryonic Specimens

Staining techniques may be used to demonstrate
various tissues and anatomical structures in intact
specimens or to show the development of an organ or
tissue at different stages of incubation. The following
procedure is for the specific staining of bone tissue.


Remove feathers or downby droppingtheembryo
into a sodium sulfide solution for a few minutes and
then washing the specimen thoroughly. For large
embryos or chicks, it may be necessary to remove the
skin from the specimen.

Fix specimen by transferring to a jar of 95%
alcohol for at least 3 days, then dehydrate with 100%
alcohol for 5 to 8 hours.

Place the embryo in acetone to extract the fat.
Several changes of acetone willbe necessarybefreall
the fat is removed. Continue changes until the fluid
remains clear.

Clear the specimen in 2% potassium hydroxide
(KOH). Change the solution until itremainselearfur
at least 2 days.

Stain the specimen by placing it in alizarin red
solution made up in potassium hydride solution.
Prepare astocksolutionoflgramalizarinred(alizarin
sodium monosulfonate) in 100 parts of water. Use 1
ml of this stock solution to 100 ml of 2% KOH.
Staining willbe complete within 12to24hours. Over-
staining may be somewhat corrected by placing the
specimen in sunlight.

Final clearing isaccompshed byinfiltratingthe
specimen with glycerin. Startwithasolutionofpart
glycerin to 4 parts KOH for 2 to 3 days. Gradually
increase glycerin until the specimen is mounted in
pure glycerin.

After the stock solutions have been prepared, it
will require 7 to 21 days for the fixing, clearing,
staining and final transfers ofeachspecimen. Several
specimens may be prepared simultaneously.

Preparation of Soft Organs
for Exhibition

Some of the hollow organs (e.g., the respiratory
system and circulatory system) maybe demontratd
by casting them (modeling true-to-life models) with
different materials. One of the most successful
materials is methyl methacrylate. A procedure for
casting organs with this material has been described
in another publication (Taylor, et aL, 1962).


Page 15






Ciaular813


PREPARATION AND DEMONSTRATION OF
VARIOUS ANATOMICAL SYSTEMS OF FOWL

Preparation of a Skeleton for Exhibition

The skeletal structure of the bird is designed for
maneuverability, speed on the ground, and the unique
ability of flight. This requires that the skeleton to be
both strong and lightweight. Compared to other
animals, the avian skeleton usually has fewer bones,
many fused bones, higher mineral content, and
pneumatic bones (hollow with pockets of air).

A mature chicken should be used for this
preparation because fully ossified bones give the best
results.

The bird should be humanely killed (carbon dioxide
gas is humane and causes no damage to the skeleton)
and as much tissue and muscle as possible removed
from the bones. Care should be taken not to damage
the bones, especially small bones of the head and ribs.
The remaining tissue can be loosened from the bone
by cooking the skeleton in boiling water for about 3
hours. The bones should be scrubbed clean with a
small brush. Soaking the bones in chlorine bleach for
about 1 hour will whiten and further clean them.

Dermestid beetles or their larvae also may be
used to clean soft tissue remnants from bone surfaces
and holes before bleaching. Approximately 6 to 10
larvae are needed for chick skeletons and
proportionally more for larger birds. Sources of
dermestid beetles include high school biology
departments, college biology or zoology departments,
and museums.

After drying, the bones may be assembled with
wire and glue and mounted on a small rod. The
skeleton may be coated with a thin coat of varnish for
protect ion. The skeleton of a chicken is illustrated in
Figure 4.

Staining Tissues of Intact
Embryonic Specimens

Staining techniques may be used to demonstrate
various tissues and anatomical structures in intact
specimens or to show the development of an organ or
tissue at different stages of incubation. The following
procedure is for the specific staining of bone tissue.


Remove feathers or downby droppingtheembryo
into a sodium sulfide solution for a few minutes and
then washing the specimen thoroughly. For large
embryos or chicks, it may be necessary to remove the
skin from the specimen.

Fix specimen by transferring to a jar of 95%
alcohol for at least 3 days, then dehydrate with 100%
alcohol for 5 to 8 hours.

Place the embryo in acetone to extract the fat.
Several changes of acetone willbe necessarybefreall
the fat is removed. Continue changes until the fluid
remains clear.

Clear the specimen in 2% potassium hydroxide
(KOH). Change the solution until itremainselearfur
at least 2 days.

Stain the specimen by placing it in alizarin red
solution made up in potassium hydride solution.
Prepare astocksolutionoflgramalizarinred(alizarin
sodium monosulfonate) in 100 parts of water. Use 1
ml of this stock solution to 100 ml of 2% KOH.
Staining willbe complete within 12to24hours. Over-
staining may be somewhat corrected by placing the
specimen in sunlight.

Final clearing isaccompshed byinfiltratingthe
specimen with glycerin. Startwithasolutionofpart
glycerin to 4 parts KOH for 2 to 3 days. Gradually
increase glycerin until the specimen is mounted in
pure glycerin.

After the stock solutions have been prepared, it
will require 7 to 21 days for the fixing, clearing,
staining and final transfers ofeachspecimen. Several
specimens may be prepared simultaneously.

Preparation of Soft Organs
for Exhibition

Some of the hollow organs (e.g., the respiratory
system and circulatory system) maybe demontratd
by casting them (modeling true-to-life models) with
different materials. One of the most successful
materials is methyl methacrylate. A procedure for
casting organs with this material has been described
in another publication (Taylor, et aL, 1962).


Page 15







Circular 813


Figure 4.
From "Avian Anatomy: Integument, Part I;" Agriculture Handbook 362; 1972; by A.M. Lucas and P.R. Stettenheim; Dept. of Poultry
Science, Michigan State University; Raynard LeNeil, illustrator.


Phalanx 1. digit III
Phalanx 1. digit IV
Phalanx 2. digit II


I Carpo iw(acarpus


-Process of metacarpus II


-Radiale


Jugal bar'
H\ old'


Styliform process


-Rilius
Olo runon
-Enit-pic~ond 1vc
.EctepicrniJN Iiv
- Humeru,
,Scapula


Deltoid crcit__
Bicipital crtrt
Triosseal j:anal
Vertebral member .'I rib-
Co'rj-co-d
Anterolateral process of -.rrmu'r-
Clavicle nI 'ui ulu. I
SternIl pin
Sternocoracoid olinl
Hypocleidlium ----
Siernal member .,I rih-
Posterolateral pars lateralis-
process of sternum pars meals-

Lateral sternal notch -
Medial sternal notch-
Carinal apex-
Patella"
Keel (carina)
External cnemial crest-


bral member .-f rib
ril Mdi.,n dorsal ridge of ilium
S .Trochanter of femur
Iliolatcral proccss
Ilioischiatic fenestra


Y gost. le


spine


--lschium
-Ischiatic process
"Pubis
Obturator foremen
emur
end of sternum


Lateral condyle(malleolus)of tibia
Ossified tibial cartilage
Lateral calcaneal ridge of
h. potarsus


Metatarsal spur


Accessory metatarsus (os metatarsus. I)


Tarsometatarsus. 11-IV



-Terminal phalanx. digit 1
-Basal phalanx. digit I .
-Basal phalanx, digit IV
-Terminal phalanx, digit IV


Page 16






Circular 813


REFERENCES AND SUGGESTED READINGS

Charts, Models and Slides on the Chick Embryo. Turtox Service Leaflet. General Biological Supply House, 761-
763 East 69th Place, Chicago 37, Illinois.

Embedding Specimens in Transparent Plastic. Turtox Service Leaflet No. 33. General Biological Supply House,
761-763 E. 69th Place, Chicago 37, Illinois

Hamilton, H.L. 1930. Lillie's Development of the Chick, (revised), New York: Henry Holt and Company.

Incubation and Brooding of Chickens. USDA Bulletin No. 1538

Incubation, Fixation and Mounting of Chick Embryos. Turtox Service Leaflet No. 17. General Biological Supply
House, 761-763 E. 69th Place, Chicago 37, Illinois.

Ouart, M.D. 1984. Poultry and Game Bird Small Flock Management. University of Florida Poultry Science
Information Series 80-1, revised.

Patten, B.M. 1951. Early Embryology of the Chick, 4th edition. New York: Blakiston Company.

Patten, B.M. 1964. Foundations of Embryology, 2nd edition. New York: McGraw-Hill, Inc.

Romanof, A.L. 1960. The Avian Embryo. New York: The MacMillan Company.

Taylor, R.O, M.A. Boone and B.D. Barnett. 1962. The use of methyl methacrylate for casting hollow organs of
the chicken. Poultry Research Series No. 15, Poultry Science Department, Clemson University, Clemson,
S.C. 29631.

Wilson, H.R, M.D. Ouart and F,B. Mather. 1984. Management Specifications. University ofFlorida Poultry
Science Series 84.2.


















COOPERATIVE EXTENSION SERVICE, UNIVERSITY OF FLORIDA, INSTITUTE OF FOOD AND AGRICULTURAL SCIENCES, Christine Taylor
Stephens, Director, in cooperation with the United States Department of Agriculture, publishes this information to further the purpose of the May
8 and June 30, 1914 Acts of Congress; and is authorized to provide research, educational information and other services only to individuals and
institutions that function without regard to race. color, age, sex, handicap or national origin. The information in this publication is available in alternate
formats. Single copies of extension publications (excluding 4-H and youth publications) are available free to Florida residents from county extension
offices. Information on copies for out-of-state purchase is available from C.M. Hinton, Publications Distribution Center, University of Florida, PO
Box 110011, Gainesville, FL 32611-0011. Information about alternate formats Is available from Educational Media and Services, University of
Florida, PO Box 110810, Gainesville. FL 32611-0810. This information was published April 1989 as Circular 813, Florida Cooperative Extension
Service. Reprinted July 1990. Revised September 1996.




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