Effect of parity on reproductive performance sows of different breeds

The aim of this study was to determine the effect of parity on reproductive performance by sows of different breeds. The sows were raised on three farms, and had seven or more litters of not fewer than seven piglets. A total of 1511 litters from various parities of Lithuanian White (N =721), Large White (N = 162) and Landrace (N = 628) sows were contained in the data that were used in this study. Multiparous sows had larger litters than primiparous sows. Piglet survival rate declined from parity 7. An increase in litter size was observed until parity 5 in Large White and until parity 6 in improved Lithuanian White (P <0.05). In comparison with parity 1, Landrace sows up to parity 5 showed not only increased prolificacy, but also increased number and litter weight of piglets at 21 days old, and the number and litter weight of weaned piglets (P <0.01). The current findings indicate that sows of these breeds can be used effectively in breeding herds until parity 5 and parity 6.