Front Cover
 Head and neck
 Fore quarters
 Examples of anatomical features...

Title: 4-H horse program : horse science
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00078697/00002
 Material Information
Title: 4-H horse program : horse science
Physical Description: Book
Creator: 4-H Youth Development Program, Florida Cooperative Extension Service, University of Florida
Publisher: 4-H Youth Development Program, Florida Cooperative Extension Service, University of Florida
Subject: University of Florida.   ( lcsh )
Spatial Coverage: North America -- United States of America -- Florida
 Record Information
Bibliographic ID: UF00078697
Volume ID: VID00002
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved, Board of Trustees of the University of Florida

Table of Contents
    Front Cover
        Page 1
        Page 2
    Head and neck
        Page 3
    Fore quarters
        Page 4 (MULTIPLE)
    Examples of anatomical features relating form to action
        Page 5
        Page 6
        Page 7
        Page 8
Full Text


The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source

site maintained by the Florida
Cooperative Extension Service.

Copyright 2005, Board of Trustees, University
of Florida

horse science








This educational material has been prepared for 4-H use by the Cooperative Extension Services of the U.S.
Department of Agriculture and State Land-Grant Universities in cooperation with the National 4-H Council and the
American Quarter Horse Association.

Trade or brand names used in the publications are used only for the purpose of educational information. The
information given herein is supplied with the understanding that no discrimination is intended and no endorsement
of products or breeds of horses by the Federal Extension Service or State Cooperative Extension Services is
implied, nor does it imply approval of products or breeds of horses to the exclusion of others which may also be

This material was originally published by the National 4-H Council, 7100 Connecticut Avenue, Chevy Chase,
Maryland 20815.

Programs and educational materials of National 4-H Council are available to all persons regardless of race, color,
sex, age, religion, national origin or handicap. Council is an equal opportunity employer.

Horse Science: Functional Anatomy and Action

Since both conformation and action need to be included
in light horse evaluation, the basic conformation features
tending to affect action must be understood. The relationship
of body parts to performance (form to function) will be here
discussed with the body of the horse divided into four areas:
1. Head and Neck, 2. Fore Quarters, 3. Body or Trunk, 4.
Rear Quarters.


The ideal head for each breed is described by the
association publications. The descriptions all say the head
should be broad in the forehead and between the eyes, short
from the eyes to the nostrils and deep in the jaws. These
words mean only that the head should be in proportion to the
parts of the body of the horse. The proportion of the head
tends to be an indication of body proportions. For example,
a long narrow head indicates a long, shallow, narrow body.

Page 3

Coarseness about the head indicates a coarse body, lacking
quality. The ear should be medium size, attractively set and
carried at a 45 degree angle to the axis of the head. Large,
full, prominent eyes of a clear deep color are desired. Small
blue eyes are considered weak. Small narrow, squinty eyes
are often correlated with coarseness in quality and a lazy,
sluggish, disposition.
Large nostrils allow for a maximum air intake and are
of prime importance because the horse cannot force air into
the lungs through the mouth as is possible in other species of
animals. All breathing of air by the horse must be done
through the nostrils.
All horses, both long and short necked ones, have seven
cervical vertebrae. The shape of the neck is due largely to
the amount and shape of the muscular tissues. The neck
should be long, lean, and attached high up on shoulders with
prominent withers. The lower part of the neck should be
attached above the point of the shoulders. The throat latch
should be cleancut and free from thick, meaty or fatty tissue
to facilitate movement of the head at the poll and allow easy






June 1989

Horse Science: Functional Anatomy and Action

Length of neck plays an important part in length of
stride. Over the neck lie several layers of muscles, some of
which control the movement of the scapula or shoulder
blade, the arm, and indirectly the forearm. The muscles that
control leg movements terminate at the knee. Cannon,
pastern and foot action is controlled by ligaments and
tendons. Larger neck muscles allow more muscle
contraction extending the arm further and raising the
forearm higher. This results in a longer stride. Another set of
muscles extend from the front of the neck to the shoulder
blade. Longer muscles here allow more shoulder blade
movement and thus a longer stride.
A thick neck adds excess weight to the front end. This
causes increased shock to the front legs because they
ordinarily carry two-thirds of the body weight of the horse.
A thick neck also decreases head movement giving slow,
awkward turns.


The withers should be prominent or high and well
defined. They should extend rearward about one-quarter of
the distance from the fore to the rear flanks. This is not
possible unless the shoulder is long and has about a 45
degree slope. Such withers give the horse opportunity to
have a long stride besides providing a good seat for the
The shoulder should be long, flat and smooth, with a 45
degree slope. This allows for increased shoulder movement
which determines the arm movement and affects the stride.
In a steep-shouldered horse the arm does not extend very far
forward during movement. This decreases extension of the
forearm and gives a short stride. Accordingly the slope of
the shoulder increases length of the muscles and allows for
more contraction and greater range of movement of the front
The legs of the horse should be attached to the trunk to
give the appearance of being on the four covers of the body.
When viewed from the front, the cannons should descend
from the center of the knees. Cannon bones should give the
appearance of being flat when viewed from the side. This
doesn't mean that the bones themselves are flat, but that
splint bones and tendons and ligaments are set apart, well
tied and give support at the posterior of the legs.
The front feet should be large, symmetrical and set at
the same angle as the pastern. The foot should be especially
wide at the heel and have considerable height at the heel as
long as it is in keeping with the desired angle.
When viewed from the side the best combination of
length for the various parts of the front quarter calls for a
long shoulder, short arm, long forearm and short cannon.
This gives a longer, more elastic stride and more speed.
A steep shoulder coupled with a long arm, short forearm
and long cannon is the most undesirable shoulder and leg
structure. This gives a severely shortened stride. Steep

Page 4

shoulders are usually associated with short, steep pasterns
giving a hard, jolting ride because of decreased shock
A long sloping shoulder also forms a more desirable
base for neck attachment giving a better balanced, more
attractive horse.


The trunk or body of the horse should be deep and
broad. The back should be short and the loin wide and
smooth. The back and loin together make up the top line
which must be strong to protect internal organs, bear the
weight of the rider and transmit to the front end the
propulsion generated by the hind legs. The loin has no bone
structure for support, making it the weakest part of the top
line. The loin is a bridge between the rib cage and the hips.
In order for the loin to perform its function of transmitting
power from the rear to front end, it must be short and
heavily muscled.
The back which must also be short and heavily muscled
gets additional support from the rib cage. Often weak backs
result from weak loins.
A short back and loin coupled with desirable shoulder
and withers results in a long underline. However, a long
underline does not insure a large body capacity unless it is
combined with long, deep, well sprung ribs. This
combination of short back and loin, long underline and long,
deep, well sprung ribs insures ample capacity for breathing
and consuming feed.
Length of underline also affects freedom of leg
movement. A short underline can cause a horse to forge.
This is striking the undersurface of the front foot with the
toe of the rear foot.


Ideal position and setting of rear leg Ideal position and slope of shoulder in relation
in relation to croup and reor postern to setting of front leg and slope of pastern

June 1989

Horse Science: Functional Anatomy and Action

The croup or rump should be long, wide and level. This
is the area from the loin to the tail head. Although the slope
of the croup differs with light horse breeds, a level croup has
longer muscles that enable a horse to take long strides and
maintain speed for great distance. A more sloping croup sets
the rear legs further under the horse so he may make a
quicker start with the more powerful stride. Regardless of
breed or slope to the croup, it should be long so the croup
muscles can make maximum contraction. All muscles in the
croup and thigh must be strong to supply the power from the
rear quarters to propel the horse.
Adequate gaskin muscling is desired. The outer gaskin
muscles help to pull the leg forward and enable propulsion,
giving the horse a long, powerful stride.
The powerful gaskin muscling also gives strength to the
legs in turning and pivoting.
The rear quarter is comparable to the forequarter in that
a long croup, short thigh, long gaskin and short cannon gives
the best stride.

A long, straight, free elastic stride and coordinated,
collected action is desirable. Excess lateral movement of the
feet and legs reduces efficiency. Action is affected by the set
of the feet and legs as well as by the anatomical
characteristics already mentioned.
Fairly close hock action with the hind legs working
beneath the body is essential.


1) A thick neck and filled throat latch gives a lack of flexion
of the head and slow. awkward turns.

Page 5

2) Horses with low, rounding withers or thick withers often
hang low-headed in the bridle and handle front legs
clumsily. They often forge.
3) Length and slope of shoulders tends to correspond to
length and slope of pasterns. Properly sloped shoulders and
pasterns (45 degrees) are related to a springy stride. Length
of shoulders and pasterns is related to the length of stride.
4) Long forearms and gaskins are related to length of stride.
5) Horses standing straight on front feet are more apt to
show straight stride and true action.
6) Short, straight shoulders give a short, straight stride with
7) If the front legs are set far out on the covers of the body,
a rolling, laboring action in front will result. This condition
often goes with thick withers and straight shoulders.
8) When points of the hocks turn slightly inward with points
of the toes slightly outward and the rear cannons parallel,
such a position of the rear legs is related to collected, rather
than spraddled, action behind.
9) When points of the hocks turn outward, often a defect in
action called limber hocks or rotating hocks occurs.
10) A calf-kneed position of the front legs gives a pounding
gait and hard concussion of feet at completion of the stride.
11) A pigeon toed horse will paddle or wing out when he
12) A splay-footed or toe-wide horse will dish or wing in
when he moves.
13) A straight stilty angle of pasterns will give a stilty
action and may give cocked ankles or other unsoundnesses
such as sidebones.

Normal foot forms even
arc in flight

Too stubby high heel and
short toe causes length-
ening of first half of
stride, long heel touches
ground earlier which
shortens last half of stride.

Long toe short heel
causes shortening of first
half of stride and length-
ening last half of stride.

June 1989

Horse Science: Functional Anatomy and Action


June 1989

Page 6

Horse Science: Functional Anatomy and Action


June 1989

Page 7

1. This document is section 2 of 14 of 4HHSGO1, which supersedes CO 201, one of a series of the 4-H Youth
Development Program, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University
of Florida. Date first printed August 1965. Date revised June 1989. Please visit the FAIRS Website at

Cooperative Extension Service
Instituteof Food and Agricultural Sciences

2. Joe B. Johnson, Washington State University. Debbie Glauer, member of 4-H Animal Science Design Team,
Department of Family, Youth and Community Science, Cooperative Extension Service, Institute of Food and
Agricultural Sciences, University of Florida, Gainesville, 32611.

Taylor Waddill, 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 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 June 1989 as CO 201, which is
superseded by 4HHSG01, Florida Cooperative Extension Service.

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