Abstract:
A total of 1780 normal first lactation records of Holstein Friesian cows kept at five herds in West Turkey during the period from 1981 to 1997 were used in this study. Genetic and phenotypic parameters for 305 day milk yield (dMY) and Age at First Calving (AFC) were estimated by MTDFREML using multi trait animal model. The model included individual and error terms as random effects, herds, season and year of calving as fixed effects and the effect of AFC on 305 dMY as a covariate. Estimates of heritability were 0.20 and 0.75 for 305 dMY and AFC, respectively. The genetic correlation between 305 dMY and AFC was negative (-0.22). Predicted breeding values for cows, dams and sires were presented.
Page(s):
114-117
DOI:
DOI not available
Published:
Journal: Pakistan Journal of Biological Sciences, Volume: 8, Issue: 1, Year: 2005