RESUMEN
This study aimed to understand the influence of the non-genetic factors that include breeding year, season, and sex of growth and development traits of Qinchuan cattle and to estimate the heritability of body weight at different growth stages. The Qinchuan cattle measurement records were by the Experiment farm of the National Beef Cattle Improvement Center (Yangling, China) from 2000 to 2017. SPSS and R software were used to analyze the influence of non-genetic factors on body size traits that include body weight (BW), withers height (WH), hip height (HH), body length (BL), chest circumference (CC), abdominal girth (AG), and calf girth (CG), at birth, 6, 12, 18, and 24 months of age. Meanwhile, the single-trait animal model of DMU software was used to estimate the variance component and the heritability of body weight. The results of GLM analysis showed as follows: sex, birth year, and birth season had effects on the body size traits of Qinchuan cattle at different growth stages. Respectively, the heritability of body weight at birth, 6, 12, 18, and 24 months of age were 0.43, 0.32, 0.37, 0.32, and 0.38.