El-Said Z. M. Oudah
Animal Production Department, Faculty of Agriculture, Mansoura University,
EI-Mansoura, Postal Code: 35 516, Egypt
Nazem A. Shalaby
Animal Production Department, Faculty of Agriculture, Mansoura University,
EI-Mansoura, Postal Code: 35 516, Egypt
Mohamed A. Mostafa
Animal Production Department, Faculty of Agriculture, Mansoura University,
EI-Mansoura, Postal Code: 35 516, Egypt
ABSTRACT
The data were used to estimate the effect of genetic (sire) and non-genetic factors on some reproductive traits, and to estimate the genetic and phenotypic parameters for the same traits. The actual means of day open (DO), number of service per conception (NSPC) and age at first calving (AFC) were, 124 days, 1.95 and 27 months, respectively. Coefficients of variation of the three studied traits were 56.9, 61.0 and 12.7%, respectively. Year of calving had highly significant effects on DO and NSPC while year of birth had highly significant effects on AFC. Month of calving had no while effect on DO and NSPC, while it had on AFC. Estimates of partial linear and quadratic regression coefficients of DO and NSPC on age at AFC were not significant. While the same were highly significant on the total milk yield (TMY) of the first lactation. The sire of heifers had highly significant effect on all traits studied. The sire variance components ( 2s) were 4.20, 2.64 and 4.08% of the total variance for DO, NSPC and AFC, respectively. The estimates of heritability (± SE) of reproductive records of the cows in their first parity based on paternal half-sibs method for DO, NSPC and AFC were 0.163 ± 0.042, 0.105 ± 0.038 and 0.163 ± 0.042, respectively. High phenotypic and environmental correlation coefficients were found between DO and NSPC (0.50 and 0.564, respectively). Low genetic correlation was found between DO and NSPC
PDF References Citation
How to cite this article
El-Said Z. M. Oudah, Nazem A. Shalaby and Mohamed A. Mostafa, 2001. Genetic and non Genetic Factors Affecting Days Open, Number of Services per Conception
and Age at First Calving in a Herd of Holstien-Friesian Cattles. Pakistan Journal of Biological Sciences, 4: 740-744.
DOI: 10.3923/pjbs.2001.740.744
URL: https://scialert.net/abstract/?doi=pjbs.2001.740.744
DOI: 10.3923/pjbs.2001.740.744
URL: https://scialert.net/abstract/?doi=pjbs.2001.740.744
REFERENCES
- Ali, I., A.A. Nasir and R.H. Mirza, 1999. Comparative performance between imported and local born holstein friesian cows maintained at LES bhunikey. Pak. J. Biol. Sci., 2: 207-208.
CrossRefDirect Link - Ali, I., R.H. Mirza and A.A. Nasir, 1999. Productive and reproductive efficiency of imported and local born jersey breed of cattle in the subtropical environment of Pakistan. Pak. J. Biol. Sci., 2: 220-221.
CrossRefDirect Link - Berger, P.J., R.D. Shanks, A.E. Freeman and R.C. Laben, 1981. Genetic aspects of milk yield and reproductive performance. J. Dairy Sci., 64: 114-122.
CrossRefDirect Link - Campos, M.S., C.J. Wilcox, C.M. Becerril and A. Diz, 1994. Genetic parameters for yield and reproductive traits of Holstein and Jersey cattle in Florida. J. Dairy Sci., 77: 867-873.
Direct Link - Hermus, S.A., C.W. Young and J.W. Rust, 1987. Genetic relationships and additive genetic variation of productive and reproductive traits in Guernsey dairy cattle. J. Dairy Sci., 70: 1252-1257.
Direct Link - Khattab, A.S. and A.A. Ashmawy, 1988. Relationships of days open and days dry with milk production in Friesian cattle in Egypt. J. Anim. Breed. Genet., 105: 300-305.
CrossRefDirect Link - Khattab, A.S. and H. Atil, 1999. Genetic study of fertility traits and productive in a local born friesian cattle in Egypt. Pak. J. Biol. Sci., 2: 1178-1183.
CrossRefDirect Link - Mantysaari, E. and L.D. van Vleck, 1989. Estimation of genetic parameters for production and reproduction in Finnish Ayrshire cattle. J. Dairy Sci., 72: 2375-2386.
Direct Link - Moore, R.K., B.W. Kennedy, L.R. Schaeffer and J.E. Moxley, 1990. Relationships between reproduction traits, age and body weight at calving and days dry in first lactation Ayrshires and Holsteins. J. Dairy Sci., 73: 835-842.
CrossRefDirect Link - Seykora, A.J. and B.T. McDaniel, 1983. Heritabilities and correlations of lactation yields and fertility for holsteins. J. Dairy Sci., 66: 1486-1493.
CrossRefPubMedDirect Link - Silva, H.M., C.J. Wilcox, W.W. Thatcher, R.B. Becher and D. Morse, 1992. Factors affecting days open, gestation length and calving interval in Florida dairy cattle. J. Dairy Sci., 75: 288-293.
CrossRefDirect Link - Simerl, N.L., C.J. Welcox and W.W. Hatcher, 1992. Postpartum performance of dairy heifers freshening at young ages. J. Dairy Sci., 75: 590-595.
Direct Link - Smith, B.A., J.S. Brinks and G.V. Richardson, 1989. Estimation of genetic parameters among reproductive and growth traits in yearling heifers. J. Anim. Sci., 67: 2881-2885.
Direct Link - Weller, J.I., R. Bar-Anan and K. Osterkorn, 1985. Effects of days open on annualized milk yields in current and following lactations. J. Dairy Sci., 68: 1241-1249.
Direct Link