|
Department of Animal Science Florida Agricultural
Research Report AL-1980-2 Experiment Station
May, 1980 Gainesville, Florida
PRODUCTIVITY OF FLORIDA NATIVE EWES OF THE
AA, BB AND AB HEMOGLOBIN TYPES
T.A. Olson and P.E. Loggins
The Florida Native sheep are descendants of sheep of mixed breeding that
were developed largely through natural selection under native range conditions
in Florida; their physical characteristics include a small mature weight, re-
fined bone structure, an open face and clean legs and underline. These sheep
have developed a degree of resistance to internal parasites; the flock from
which these data were collected having been maintained without the use of
anthelmintics since 1962. The objective of this report is to examine measures
of productivity of Florida Native ewes of three hemoglobin types.
Experimental Design
The Florida Native sheep included in this study descended from a foun-
dation purchased from four locations in Florida in 1956. The ewes were
divided into breeding groups based on hemoglobin type and bred to rams of the
same hemoglobin type. They were maintained as a single flock except during the
forty day breeding season which began July 1. The data collected on the ewes
included pregnancy rate, numbers of lambs born, weight at the beginning of the
breeding season (August), prior to lambing (November), and after weaning of
their lambs (February). Hemoglobin levels (gms/100 ml) were eval-
uated at the same times as weights were recorded. Birth and weaning (60 day)
weights as well as weights at approximately 120 days, survival rate and hemoglobin
levels at weaning were recorded on the progeny of ewes of each hemoglobin type.
The data collected on ewes were analyzed by least squares procedures using
models that included the main effects of year, hemoglobin type, ewe age, and
interactions with F values over 1. The models used in analysis of lamb data
included the effects used in the ewe analyses plus sex, birth type (single or
twin) and interactions of importance.
Results and Discussion
Data from 568 records of ewes exposed to breeding and 500 lambs produced
from 1978 to 1977 were used in this study. Table 1 contains the least squares
means of data relating to ewe productivity. Type BB ewes had a higher (P<.02)
pregnancy rate than type AA and surpassed (P<.01) type AB but not type AA
(P<.05) in lamb survival rate. Numbers of ewes producing twins did not sign-
ificantly vary between groups. By combining pregnancy percentage, number of
lambs born per ewe and ewe survival into a single value, lambs weaned per 100
ewes bred can be estimated. This value cannot be analyzed statistically but
BB ewes (94) far surpassed either AA (79) or AB (75) ewes.
Department of Animal Science Florida Agricultural
Research Report AL-1980-2 Experiment Station
May, 1980 Gainesville, Florida
PRODUCTIVITY OF FLORIDA NATIVE EWES OF THE
AA, BB AND AB HEMOGLOBIN TYPES
T.A. Olson and P.E. Loggins
The Florida Native sheep are descendants of sheep of mixed breeding that
were developed largely through natural selection under native range conditions
in Florida; their physical characteristics include a small mature weight, re-
fined bone structure, an open face and clean legs and underline. These sheep
have developed a degree of resistance to internal parasites; the flock from
which these data were collected having been maintained without the use of
anthelmintics since 1962. The objective of this report is to examine measures
of productivity of Florida Native ewes of three hemoglobin types.
Experimental Design
The Florida Native sheep included in this study descended from a foun-
dation purchased from four locations in Florida in 1956. The ewes were
divided into breeding groups based on hemoglobin type and bred to rams of the
same hemoglobin type. They were maintained as a single flock except during the
forty day breeding season which began July 1. The data collected on the ewes
included pregnancy rate, numbers of lambs born, weight at the beginning of the
breeding season (August), prior to lambing (November), and after weaning of
their lambs (February). Hemoglobin levels (gms/100 ml) were eval-
uated at the same times as weights were recorded. Birth and weaning (60 day)
weights as well as weights at approximately 120 days, survival rate and hemoglobin
levels at weaning were recorded on the progeny of ewes of each hemoglobin type.
The data collected on ewes were analyzed by least squares procedures using
models that included the main effects of year, hemoglobin type, ewe age, and
interactions with F values over 1. The models used in analysis of lamb data
included the effects used in the ewe analyses plus sex, birth type (single or
twin) and interactions of importance.
Results and Discussion
Data from 568 records of ewes exposed to breeding and 500 lambs produced
from 1978 to 1977 were used in this study. Table 1 contains the least squares
means of data relating to ewe productivity. Type BB ewes had a higher (P<.02)
pregnancy rate than type AA and surpassed (P<.01) type AB but not type AA
(P<.05) in lamb survival rate. Numbers of ewes producing twins did not sign-
ificantly vary between groups. By combining pregnancy percentage, number of
lambs born per ewe and ewe survival into a single value, lambs weaned per 100
ewes bred can be estimated. This value cannot be analyzed statistically but
BB ewes (94) far surpassed either AA (79) or AB (75) ewes.
Ewe weights and hemoglobin levels (gms/100 ml) by hemoglobin type at the
initiation of the breeding season (August), prior to lambing (November), and
at the weaning of their lambs (February) are shown in tables 2 and 3. Type
BB ewes were consistently the lightest and Type AA ewes the heaviest, but only
in November was the difference significant at the .05 level. Ewes of Type
AB were always intermediate in weight between types AA and BB but never did
they differ significantly from either type AA or BB.
Ewe hemoglobin levels, however, were always very highly significantly
(P<.001) different regardless of the month of measurement (Table 3). Type AA
ewes were always heaviest, type BB ewes lightest and type AB ewes intermediate
between them. The hemoglobin types thus rank in the same order for hemoglobin
level as they do for weight. This ranking, however, is the reverse of the
ranking observed for pregnancy rate. This occurred in spite of the fact that
ewes which became pregnant were highly significantly heavier (P .002) than
ewes which failed to conceive (40.3 vs. 38.6 kgs). The ewes becoming pregnant
also had highly significantly (P<.OOT1 higher hemoglobin levels during the
breeding season than the ewes which were infertile (7.01 vs. 6.15 gms/100 ml).
Thus it appears clear that in general the ewes with higher hemoglobin levels are
more fertile, in contrast to the situation with regard to hemoglobin type where
the type with the lowest hemoglobin levels (type BB) was the most fertile. An
explanation for these conflicting results is not readily apparent.
Differences in lamb performance due to ewe hemoglobin type were not
striking (Table 4.) The lambs from AB ewes were heavier at birth (P<.05) than
those from either AA or BB ewes, but no significant differences were present at
weaning. Lambs from AA ewes gained slower (P<.05) than those from BB or AB
ewes. The lowered growth rate of the lambs from AA ewes did not appear to
be the result of greater parasitism as they has the highest (P<.001) hemoglobin
levels. Again the paradoxical situation is seen in that the lambs of the
hemoglobin type with the highest hemoglobin level show the lowest performance.
Summary
Ewes of Florida Native breeding of these hemoglobin types (AA, BB and
AB) were mated to rams of their hemoglobin type and their pregnancy rate,
rate of lamb production andlamb survival rate, birth weight, weaning weight
and postweaning average daily gain were recorded over a five year period.
Hemoglobin levels (gms/100 ml of blood) were also measured on the ewes at the
beginning of the breeding season, prior to lambing and at the weaning of their
lambs. Lamb hemoglobin levels were also measured at weaning. The type BB
ewes had the lowest hemoglobin levels but surpassed the AB and AA ewes in
pregnancy rate and lamb survival rate to weaning. There were only small
differences in lambs born per pregnant ewe and lamb growth traits. These
results indicate that hemoglobin type may have some value as an indicator
of fertility and survival and could, therefore, be useful as a selection tool
for these traits.
Table 1. Ewe productivity
e Bood Ty Pregnancy Number of Lamb Lambs Weaned
we Blood Type percentage Lambs Born/Ewe Survival Per 100 Ewes Bred
AA 75.03.3a 1.13.03a 93.22.0a,b 79
BB 86.04.0b 1.15.03a 95.82.0a 94
AB 80.03.2a, 1.07.03a 87.92.0b 75
'Means-with the same letter as a superscript do not differ significantly
at the .05 level.
Table 2. Ewe weights
Ewe Month
Hemogl-obin
Type August November February
AA 39.9.5a 41.9.6a 38.5.5a
BB 39.0.5a 40.0.5b 37.3.5a
AB 39.3.4a 41.0.4a'b 38.1.4a
abMeans with the same letter as a superscript do not
differ significantly at the .05 level.
Table 3. Ewe hemoglobin levels (gms/100
ml)
Ewe Hb Type August November February
Hb Level Hb Level Hb Level
AA 7.2.14a 7.8.17a 7.1.15a
BB 6.1.17b 6.9.21b 6.2.19b
AB 6.5.13c 7.4.16c 6.7.14c
a,',cMeans with
not differ
the same letters as superscripts do
significantly at the .05 level.
Table 4. Lamb performance and hemoglobin levels
Birth
Weight (kg)
3.3.04a
3.2.04a
3.4.09b
Lamb Hb Level
:at Weaning
(gms/100 ml)
10.3.13a
8.8.13b
9.4.13c
Post Wean
Average Daily
Gain (kg/day)
.136.004a
.147.004b
.147.004b
150 Day
Weight (kg)
20.5.38a
21.3.38ab
21.7.37b
Weaning
Weight (kg)
12.3+.24a
12.5+.23a
12.9.23a
CMeans with the same letters as superscripts do not differ significantly at the .05 level.
Hb Type
AA
BB
AB
--
Table 1. Ewe productivity
e Bood Ty Pregnancy Number of Lamb Lambs Weaned
we Blood Type percentage Lambs Born/Ewe Survival Per 100 Ewes Bred
AA 75.03.3a 1.13.03a 93.22.0a,b 79
BB 86.04.0b 1.15.03a 95.82.0a 94
AB 80.03.2a, 1.07.03a 87.92.0b 75
'Means-with the same letter as a superscript do not differ significantly
at the .05 level.
Table 2. Ewe weights
Ewe Month
Hemogl-obin
Type August November February
AA 39.9.5a 41.9.6a 38.5.5a
BB 39.0.5a 40.0.5b 37.3.5a
AB 39.3.4a 41.0.4a'b 38.1.4a
abMeans with the same letter as a superscript do not
differ significantly at the .05 level.
Table 3. Ewe hemoglobin levels (gms/100
ml)
Ewe Hb Type August November February
Hb Level Hb Level Hb Level
AA 7.2.14a 7.8.17a 7.1.15a
BB 6.1.17b 6.9.21b 6.2.19b
AB 6.5.13c 7.4.16c 6.7.14c
a,',cMeans with
not differ
the same letters as superscripts do
significantly at the .05 level.
Table 4. Lamb performance and hemoglobin levels
Birth
Weight (kg)
3.3.04a
3.2.04a
3.4.09b
Lamb Hb Level
:at Weaning
(gms/100 ml)
10.3.13a
8.8.13b
9.4.13c
Post Wean
Average Daily
Gain (kg/day)
.136.004a
.147.004b
.147.004b
150 Day
Weight (kg)
20.5.38a
21.3.38ab
21.7.37b
Weaning
Weight (kg)
12.3+.24a
12.5+.23a
12.9.23a
CMeans with the same letters as superscripts do not differ significantly at the .05 level.
Hb Type
AA
BB
AB
--
Table 1. Ewe productivity
e Bood Ty Pregnancy Number of Lamb Lambs Weaned
we Blood Type percentage Lambs Born/Ewe Survival Per 100 Ewes Bred
AA 75.03.3a 1.13.03a 93.22.0a,b 79
BB 86.04.0b 1.15.03a 95.82.0a 94
AB 80.03.2a, 1.07.03a 87.92.0b 75
'Means-with the same letter as a superscript do not differ significantly
at the .05 level.
Table 2. Ewe weights
Ewe Month
Hemogl-obin
Type August November February
AA 39.9.5a 41.9.6a 38.5.5a
BB 39.0.5a 40.0.5b 37.3.5a
AB 39.3.4a 41.0.4a'b 38.1.4a
abMeans with the same letter as a superscript do not
differ significantly at the .05 level.
Table 3. Ewe hemoglobin levels (gms/100
ml)
Ewe Hb Type August November February
Hb Level Hb Level Hb Level
AA 7.2.14a 7.8.17a 7.1.15a
BB 6.1.17b 6.9.21b 6.2.19b
AB 6.5.13c 7.4.16c 6.7.14c
a,',cMeans with
not differ
the same letters as superscripts do
significantly at the .05 level.
Table 4. Lamb performance and hemoglobin levels
Birth
Weight (kg)
3.3.04a
3.2.04a
3.4.09b
Lamb Hb Level
:at Weaning
(gms/100 ml)
10.3.13a
8.8.13b
9.4.13c
Post Wean
Average Daily
Gain (kg/day)
.136.004a
.147.004b
.147.004b
150 Day
Weight (kg)
20.5.38a
21.3.38ab
21.7.37b
Weaning
Weight (kg)
12.3+.24a
12.5+.23a
12.9.23a
CMeans with the same letters as superscripts do not differ significantly at the .05 level.
Hb Type
AA
BB
AB
--
Table 1. Ewe productivity
e Bood Ty Pregnancy Number of Lamb Lambs Weaned
we Blood Type percentage Lambs Born/Ewe Survival Per 100 Ewes Bred
AA 75.03.3a 1.13.03a 93.22.0a,b 79
BB 86.04.0b 1.15.03a 95.82.0a 94
AB 80.03.2a, 1.07.03a 87.92.0b 75
'Means-with the same letter as a superscript do not differ significantly
at the .05 level.
Table 2. Ewe weights
Ewe Month
Hemogl-obin
Type August November February
AA 39.9.5a 41.9.6a 38.5.5a
BB 39.0.5a 40.0.5b 37.3.5a
AB 39.3.4a 41.0.4a'b 38.1.4a
abMeans with the same letter as a superscript do not
differ significantly at the .05 level.
Table 3. Ewe hemoglobin levels (gms/100
ml)
Ewe Hb Type August November February
Hb Level Hb Level Hb Level
AA 7.2.14a 7.8.17a 7.1.15a
BB 6.1.17b 6.9.21b 6.2.19b
AB 6.5.13c 7.4.16c 6.7.14c
a,',cMeans with
not differ
the same letters as superscripts do
significantly at the .05 level.
Table 4. Lamb performance and hemoglobin levels
Birth
Weight (kg)
3.3.04a
3.2.04a
3.4.09b
Lamb Hb Level
:at Weaning
(gms/100 ml)
10.3.13a
8.8.13b
9.4.13c
Post Wean
Average Daily
Gain (kg/day)
.136.004a
.147.004b
.147.004b
150 Day
Weight (kg)
20.5.38a
21.3.38ab
21.7.37b
Weaning
Weight (kg)
12.3+.24a
12.5+.23a
12.9.23a
CMeans with the same letters as superscripts do not differ significantly at the .05 level.
Hb Type
AA
BB
AB
--
|
RSS
HIDE
