Abstract: In this study, author analyzed the relationship of swine litter size alive and uniformity of newborn piglets in Suzhong pure line and hybrid line, the results showed that with the increase in the number of swine litter size alive, average of newborn piglets weight gradually decreased, the standard deviation gradually increased, and uniformity gradually decreased. In Suzhong pure line, there was a positive correlation between swine litter size alive and the standard deviation, the difference reached a significant level (P<0.05); and existed a negative correlation with the average, the difference was extremely significant level (P<0.01); In Suzhong hybrid line, there was a positive correlation between swine litter size alive and the standard deviation, the difference reached a extremely significant level (P<0.01), and existed a negative correlation with the average, the difference was extremely significant level (P<0.01). At the same time, in different range of litter size, swine litter size alive significantly influenced average and the standard deviation of newborn piglets weight, there was a better economic range between swine litter size alive and uniformity of newborn piglets.

Key words: swine; litter size alive; uniformity; relationship