Estimation of genetic parameters for growth-related traits and evaluating the results of a 27-year selection program in Baluchi sheep

摘要: Abstract The aim of the present study was to estimate (co) variance components and genetic parameters for growth traits Baluchi sheep as well response selection yearling live weight. Data pedigree information used in this were collected at Abbasabad Sheep Breeding Station from 1983 2011. Studied birth weight (BW), 3-month (W3), 6-month (W6), 9-month (W9) (W12). Six different animal models fitted, including or ignoring maternal effects. Estimates breeding values obtained by best linear unbiased prediction (BLUP) method. Genetic trends studied estimated regressing mean on year. On four gametic pathways, generation intervals average age parents their progeny. estimates direct heritability ( h 2 ) low ranged between 0.03 (W6) 0.15 Maternal environmental effects significant studied. m 0.09 but decreased gradually reached 0.02 age. Likewise, permanent environment a proportion phenotypic c 0.13 0.05 Phenotypic correlations various positive increased with older pairs ages. corresponding all positive, tendency higher changes over experiment −0.13 kg, 0.192 kg, 0.082 kg, 0.147 kg 0.459 kg BW, WW, W6, W9 W12, respectively. Annual gain W12 were, respectively, ≈0.00 g, 7g, 4g, 7 g 14 g per interval 3.50 years. lower observed ram side compared dam (3.35 year vs. 3.81 year), indicating faster turnover sires than dams. Overall, results showed moderate improvement sheep. In addition, because growth-related sheep, have an accurate evaluation, these need be considered any program aimed improving breed.