Genetic and phenotypic aspects of functional stayability traits in the Murciano-Granadina goats

Data consisted of pedigree information and kidding records from ۷,۵۴۱ Murciano-Granadina goats collected between ۲۰۱۸ and ۲۰۲۳, 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 ۲۴ months (Stay۲۴), ۳۶ months (Stay۳۶), and ۴۸ months (Stay۴۸) after first kidding. The averages for the functional stayability until ۲۴, ۳۶, and ۴۸ months after first parity were ۸۱%, ۵۲%, and ۳۰%, respectively. Kidding year and milk yield level were statistically significant risk factors for all the investigated stayability traits (P<۰.۰۱). 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 ۰.۰۸±۰.۰۳, ۰.۰۶±۰.۰۲, and ۰.۱۸±۰.۰۶, for Stay۲۴, Stay۳۶, and Stay۴۸, respectively. Posterior means±PSD for genetic correlations among the studied traits were positive estimates of ۰.۸۲±۰.۱۷ (Stay۲۴-Stay۳۶), ۰.۷۴±۰.۱۹ (Stay۲۴-Stay۴۸), and ۰.۶۸±۰.۱۹ (Stay۳۶-Stay۴۸).  The phenotypic correlation estimates were ۰.۹۳±۰.۰۱, ۰.۸۹±۰.۰۳, and ۰.۹۴±۰.۰۱ for Stay۲۴-Stay۳۶, Stay۲۴-Stay۴۸, and Stay۳۶-Stay۴۸, 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.

کلیدواژه ها:

Bayesian approach ، dairy goat ، functional stayability ، genetic correlation ، heritability