ESTIMATION OF GENETIC VALUES OF HOLSTEIN BULLS ACCORDING TO SOME GROWTH TRAITS

A total of 1010 records of growth traits from progenies of 16 Holstein sires, at al-Naser dairy station, United Livestock Co. Ltd. in Al-Soweira (50 km south of Baghdad) were genetically analyzed. The study was conducted to estimate Best Linear Unbiased Prediction (BLUP) of sires for birth and weaning weights and gain from birth to birth. Genetic parameters (heritability, genetic and phenotypic correlations between above traits) were also estimated. General Linear Model (GLM) within the SAS program was used to study the effect of fixed factors (parity, sex, type of birth, season and year of parturition) on growth traits. Restricted Maximum Likelihood (REML) was conducted to estimate variance of components of random effects assuming mixed model. Harvey program was used to estimate BLUP. Results indicated that heritability of birth and weaning weight and gain from birth to weaning were 0.36, 0.28 and 0.41, respectively, The highest genetic and phenotypic correlations (0.86 and 0.91) were between weaning weight and weight gain, while the lowest correlations (0.63 and 0.55) were between birth and weaning, respectively. The highest BLUP was 4.12 kg, while the lowest was -5.15 kg of birth weight. The highest BLUP was 9.08 kg, while the lowest was -8.31 kg of weaning weight. However, the highest BLUP was 2.71 kg, while the lowest was -2.51 kg of weight gain, respectively. It was suggested that 4 sires can be selected to be parents of next generation.