Estimates of genetic parameters and sire evaluation for growth traits in friesian calves in Egypt

Data used in this study were collected over a period of ten years (from 1985 to 1994) from two farms belonging to the Egyptian Company for Meat and Milk Production, Ministry of Agriculture, Egypt. Live body weights of 1110 Friesian calves (650 male and 460 Female) progeny of 22 sires were used in the present study. Sires with at least 10 daughters were used in the statistical analysis using Harvey (1990) program. Unadjusted means of birth weight, weight at three, six, nine and twelve months of age were 30.1, 78.7, 121.8, 165.1 and 204.4 kg, respectively. Average daily gain were 0.556, 0.521, 0.498, 0.468 and 0.502 kg/day during the period from birth to three months of age, 3 to 6.6 to 9.9 to 12 and from birth to twelve months of age. Heritability estimates of birth weight, weight at 3, 6, 9 and 12 months of age were 0.12,0. 19,0. 10,0.17 and 0.18 and for daily gain from birth to three months of age, 3 to 6.6 to 9.9 to 12 were 0.19, 0.03, 0.07 and 0.18, respectively. Genetic correlations among both weights at different ages all ranged from 0.25 and 0.99. All genetic correlations between body weights, and body weight gains were positive except, that between birth weight and each of gain from birth to three months of age and from three to six months of age, and between weight at three months and each of gain from three months to six months of ages and gain from nine to twelve months of age. Sire transmitting abilities (ETAs) ranged from -1.138 to 1.046 for birth weight, from -2.423 to 2.939 for weight at three months of age, while ETA estimates for daily gain from GO-3 and G3-6 were 0.059 and 0.017 kg/day, respectively. All Spearman rank correlation coefficients among ETAs of studied traits were positive. The results indicated the presence of great variation in growth traits. Selection would lead to improve the growth rate in Friesian calves under Egypt conditions