برآورد پارامترهاي ژنتيكي صفات توليد مثل تركيبي در ميش نژاد بلوچي

Estimates of Genetic and Phenotypic Parameters for Composite Reproductive Traits in Baluchi Ewes

Records of 2593 baluchi ewes, obtained from Baluchi Sheep Breeding Station in Abbas Abad, Mashhad, were used to estimate genetic parameters for total weight of lamb weaned per ewe joined (TWWfWJ) in different parities. Estimates of heritability for TWWI/EJ, TWW2IEJ, TWW3.EJ and TWW4IEJ were 0.112 ± 0.030, 0.028 ± 0.030, 0.075 ± 0.060 and 0.135 ±0.120, respectively. Direct additive genetic correlations were positive and high, to medium ranging from 0.955 (between TWWllEJ and TWW2IEJ) to 0.362 (between TWW2/EJ and TWW4IEJ). The corresponding estimates for phenotypic correlations were also positive. but lower than genetic correlations and varied from 0.147 (between TWW3/EJ and TWW4/EJ) to 0.204 (between TWW2/EJ and TWW4IEJ). The high genetic correlation between TWWIIEJ and other composite reproduction traits indicated that lifetime reproductive perfomance can be improved through selection for TWWIIEJ.