【Objective 】 To estimate genetic parameters of growth traits of Large White pigs in Wens Group,and study the effects of change in method for measuring backfat(A to B ultrasonic) and variation in final body mass(age at 100 kg to age at 115 kg body mass) on pig breeding.【Method】Single/multitrait animal model and DMU software were used to estimate genetic variance and variance of common litter effects for age at 100 kg body mass(AGE) and backfat thickness at 100 kg body mass(BF).We evaluated the pearson and sp...