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Heritability, genetic correlation and breeding value for some productive
and reproductive traits in Holstein cows
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El-Bayoumi KM1, El-Tarabany MS1, Abdel-Hamid
TM1* and Mikaeil OM2 |
1Animal
Wealth Development Department, Faculty of Veterinary Medicine, Zagazig
University, Sharkia, Egypt; 2Omar El-Mokhtar University, El-Byda,
Libya
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Abstract |
The objective of this study was to estimate the genetic parameters
(heritability, genetic correlation) and breeding value for some
productive and reproductive traits. Such traits include calving interval
(CI), days open (DO), days in milk (DIM), dry period (DP), total milk
yield (TMY) and 305-day milk yield (305-DMY). Accurate 3464 records of
Holstein (HO) cows were utilized. Animal model was used to estimate
heritability and breeding value. Strong negative genetic correlation
was estimated for both CI and DP with TMY and 305-DMY ranged from (-0.65
to -0.99). High positive genetic associations were recorded for both CI
with DO, DP and DO with DP.
Weak heritability was estimated for CI, DO, DP and DIM ranged from
0.002-0.12 while for TMY and 305-DMY, the estimates were medium being
0.34±0.02 and 0.32±0.02 respectively. The range of breeding value for
cows and sires were high for most of studied traits. The range of
breeding value of cows for TMY and 305-DMY was
4213
and
688.80
kg respectively which was higher than those for sires (3485
and
623
kg respectively) and dams (2281
and
417.80
kg respectively). In conclusion, improvement of reproductive traits (CI,
DO) through selection is difficult, but required improvement of
managerial and environmental conditions. Higher ranges of breeding
values for cows and sires for most of studied traits indicate higher
genetic variation and higher opportunity for selection of top cows and
sires in breeding value, which would result in rapid genetic progress in
the future generations.
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Keywords:
Heritability; genetic correlation; breeding value; days open; Holstein |
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To cite this article:
El-Bayoumi KM, MS El-Tarabany, TM Abdel-Hamid and
OM Mikaeil,
2015.
Heritability, genetic correlation and breeding value for some productive
and reproductive traits in Holstein cows.
Res.
Opin. Anim. Vet. Sci., 5(2): 65-70. |
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