Abstract
This study aimed to estimate the variance, heritability, and genetic correlation of growth traits in Inner Mongolia white cashmere goats (Erlangshan type) (IMWCG-ER). Data collected from the Erlang Mountain Ranch in 2022-2023 were analyzed. The traits studied included birth weight (BW), weaning weight (WW), pre-weaning daily gain (ADG), and the 12-month weight (12W). In animal models, single and multi-trait analyses were performed using the restricted maximum likelihood (REML) method to estimate genetic parameters, and six different models were fitted for each trait by ignoring or including maternal permanent environmental effects, maternal additive genetic effects, and the interaction with individual additive genetic effects. The accuracy and suitability of each model were tested using the likelihood ratio and AIC and BIC tests. The heritability estimates of birth weight, weaning weight, daily gain before weaning, and the 12-month weight were 0.3884, 0.2951, 0.2749, and 0.2192, respectively. The absolute value of the genetic correlation coefficient between traits ranged from -0.8700 to 0.5529. The highest genetic association was between birth weight and pre-weaning daily gain (-0.8700), followed by birth weight and the 12-month weight (-0.6256). The absolute value of phenotypic correlation coefficients ranged from -0.7906 to 0.3562. The highest phenotypic correlation was between birth weight and daily gain before weaning, and the correlation coefficient was -0.7906.