Genetic analysis and the estimates of genetic and phenotypic correlation of growth rates, Kleiber ratios, and fat-tail dimensions with birth to yearling live body weight traits in Makuie sheep

Genetic parameter estimates of growth rates, Kleiber ratios, and fat-tail dimensions were aimed using 22, 253 records at the present study. The studied traits were average daily gain from birth to weaning, average daily gain from 9 months of age to yearling, Kleiber ratio from birth to weaning, Kleiber ratio from 9 months of age to yearling, fat-tail length, fat-tail width, and fat-tail thickness. Each trait was fitted by four different animal models, which are differentiated by including or excluding maternal effects. Beside the estimates of genetic and phenotypic correlation among the studied traits, the association of them with birth to yearling live body weights using series of bivariate animal models was investigated. The direct heritabilities were ranged from 0.04 to 0.20, which indicated a wide range of additive genetic variances of the traits. Genetic and phenotypic correlations between the main traits were ranged from −0.11 to 0.99 and −0.08 to 0.95, respectively. The results indicated that the traits could be improved by including them in the selection index due to their moderate to high heritability estimation.