Abstract: It had compared reproductive performance of Sutai pigs with different litters,as well as shown relationships between some parameters in gilts,such as birth weight,weaning weight (35 days),4 month weight and 6 month weight,and their reproductive performance. The study aimed to further understanding of the Sutai pigs' reproductive performance,and to guide the selection of gilts. The results showed that both litter size and survival rate of primiparous sows were lowest in subsequent parities (up to parity 6) when litter 4 had the highest survival rate. Reproductive performance of sows had been stabilized at a higher level from litter 3,which could be an important basis in eliminating gilts. Sutai gilts' weaning weight (35 days) had significant effect on both 4 month weight and 6 month weight. 6 month weight was also significantly influenced by 4 month weight. However,the relationship between early performance in sows and their subsequent reproductive performance was not significant. Therefore it was much economical of selecting gilts with little weaning weight (35 days) than others.

Key words: Sutai pig; reproductive performance; selection; litter