Effects of the higher parity and litter size on piglet birth weight and survival rate of later born piglets

Abstract

The objectives of this study were to evaluate the effects of higher parity and litter size (LS) on piglet birth weight (BW) and to compare the BW and survival rate of piglets born in different birth orders (BO). The study was conducted at a commercial pig farm in Thailand. Data from 230 sows and 3,500 piglets were analyzed including parity, litter size (LS), average birth weight (AvBW), coefficient of variation of piglets’ BW (%CV), standard deviation of piglets’ BW (SD), percentage of small piglets (%Small), individual piglet’s BW, piglet birth order (BO; 1-10, 11-16, 17-25), sex and characteristics at birth (mummified fetuses (MM), stillborn piglets (SB) and born alive piglets (BAL)). Results revealed that the reduction in AvBW was prominent when LS increased (p < 0.001) and the expansion of BW variability (%CV, SD, %Small) was significant in the higher parity sows with large LS (p < 0.001). A difference in piglet BW was found among different BO; the later born piglets in BO 17-25 were lighter than the piglets born in BO 1-10 and 11-16 (p < 0.001). The percentage of BAL steadily decreased concomitantly with the rising of BO (p < 0.001), whereas the born dead piglets including MM and SB increased significantly (p < 0.001). This study demonstrated that higher parity and LS had negative effects on piglet BW including the reduction in mean BW with a greater variability. Moreover, the later born piglets in large litters had a lower survival rate.