GENETIC PARAMETERS FOR DIRECT AND MATERNAL EFFECTS AND AN ESTIMATION OF BREEDING VALUES FOR BIRTH WEIGHT OF HOLSTEIN FRIESIAN CALVES

KAYGISIZ, A., G. BAKIR and I. YILMAZ, 2012. Genetic parameters for direct and maternal effects and an estimation of breeding values for birth weight of Holstein Friesian calves. Bulg. J. Agric. Sci., 18: 117-124 In this study, genetic and phenotypic parameters for birth weight in Holstein calves raised at Tahirova and Polatli State Farms were estimated. Analysis of the results showed that the least squares means of birth weight were 38.71 +/- 3.56 and 37.53 +/- 2.09 kg for the calves raised at state farms at Tahirova and Polatli, respectively. The effects of birth year, season and sex on birth weight were significant (P < 0.05) or highly significant (P < 0.01). The effect of calving parity on birth weight was highly significant (P < 0.01) for state farm at Tahirova, but insignificant for state farm at Polatli. Direct heritability (h(d)(2)), maternal heritability (h(m)(2)), total heritability (h(T)(2)) and the fraction of variance due to maternal permanent environmental effects (c(2)) were 0.15, 0.56, 0.12 and 0.0004, respectively for calves raised at state farm at Tahirova. Direct heritability (h(d)(2)), maternal heritability (h(m)(2)), total heritability (h(T)(2)) and the fraction of variance due to maternal permanent environmental effects (c(2)) were 0.04, 0.002, 0.039 and 0.002, respectively for calves raised at state farm at Polatli. It was concluded that the effects of environmental factors should be eliminated for the implementation of effective selection program to be conducted on birth weight in Holstein calves.