مرتضی مختاری

Data consisted of pedigree information and kidding records from 7,541 Murciano-Granadina goats collected between 2018 and 2023, from a commercial dairy farm in Ghale-Ganj City, southern Kerman province, Iran, were used. The functional stayability traits were defined as binary traits and included stayability until 24 months (Stay24), 36 months (Stay36), and 48 months (Stay48) after first kidding. The averages for the functional stayability until 24, 36, and 48 months after first parity were 81%, 52%, and 30%, respectively. Kidding year and milk yield level were statistically significant risk factors for all the investigated stayability traits (p<0.01). Genetic analysis was performed by applying a Bayesian multivariate threshold animal model via Gibbs sampling. Posterior means of heritability estimates ± posterior standard deviation (PSD) were 0.08 ± 0.03, 0.06 ± 0.02, and 0.18 ± 0.06, for Stay24, Stay36, and Stay48, respectively. Posterior means ± PSD for genetic correlations among the studied traits were positive estimates of 0.82 ± 0.17 (Stay24-Stay36), 0.74 ± 0.19 (Stay24-Stay48), and 0.68 ± 0.19 (Stay36-Stay48). The phenotypic correlation estimates were 0.93 ± 0.01, 0.89 ± 0.03, and 0.94 ± 0.01 for Stay24-Stay36, Stay24-Stay48, and Stay36-Stay48, respectively. Given the low heritability estimates, improving environmental conditions and potentially incorporating non-additive genetic effects in future breeding schemes may be more important for enhancing functional stayability of the Murciano-Granadina goat in the flock.