Estimation of genetic parameters for growth traits and fleece production of South Khorasan goats

In this study, genetic parameters and (co)variance components were estimated for weights at birth, 3, 6, 9, 12, 24 months, daily weight gain from birth to 3 months and daily weight gain from 3 month to 12 month, Keliber ratio from birth to 3 months and Keliber ratio from 3 to 12 month, and production of fleece for South Khorasan goats at Sarbisheh station over a period of 16 years (1996–2012). Records of 2544 kids, the progeny of 149 sires and 851 dams were used in the study. Analyses were carried out by MTGSAM program. Six different animal models were fitted for all traits. The most appropriate model was model 2 with only permanent environmental maternal effects. Estimates of direct heritability varied from 0.01 for weight at 12 months to 0.49 for production of fleece. Maternal effects are important sources of variation on growth traits significantly and ignoring maternal effects in the model would cause inaccurate genetic evaluation of kids. Bivariate analysis was also used to estimate correlations between traits. Direct genetic correlations among studied traits ranged from 0.01 for daily weight gain and Keliber ratio from birth to 3 months and 3 to 12 month-almost traits to 0.88 for weight at 3 months- Keliber ratio from birth to 3 months. Phenotypic and environmental correlations were generally lower than those of genetic correlations