Effects of Parity Number on Some Reproductive Parameters in Landrace x Yorkshire Sows

Abstract

In this study, we evaluated the effects of parity on different reproductive parameters including gestation length (GL), litter size (LS), litter birth weight (LBW), mean individual birth weight (MBW), and number of born dead piglets per litter (BDP) in Landrace x Yorkshire sows. Data was collected from 773 litters born from 773 sows raised on one farm in Northern Vietnam. Based on parity number, sows were categorized into 5 groups, i.e., 1, 2, 3-5, 6-7, and >7. One-way analysis of variance tests was used to compare the GL, LS, LBW, MBW, and BDP among the 5 groups. Results showed that parity significantly affected all the studied reproductive parameters. GL was longest in parities 1 and 6-7 (P<0.05). LS, LBW, and MBW were lowest in parity 1 (P<0.05) and remained stable in the later parities. BDP increased when the parity increased with the lowest value in parity 1 and highest values in parities 6-7 and >7 (P<0.05). This result enriches the understanding of the effect of parity on reproductive performance and may contribute to the management and culling strategies on farms to maximize the farm’s benefit.