Influence of previous lactation duration on the reproductive performance of Large White and Landrace sows under purebred breeding

Abstract

The study presents the results on the effect of the duration of previous lactation on the reproductive performance of sows of major maternal breeds. It has been established that Large White sows have advantages over Landrace breed counterparts in litter size, birth weight of the litter, and number of weaned piglets. At the same time, Landrace animals had advantages in terms of the weight of individual piglets and the weight of the litter at weaning. The duration of previous lactation significantly influences the reproductive capacity of sows of both breeds. In the first and third groups where the duration of previous lactation lasted 23.3–24.74 % longer than in the second and fourth groups, the number of piglets born in animals with standard lactation increased by 3.1 % in Landrace and by 5.3 % in large white breeds. A similar trend was observed in terms of litter size – with 5.0–5.7 % more piglets in both breeds under standard lactation. The birth weight of piglets in sows with standard lactation was significantly higher by 5.2 % in Large White and by 10.2 % in Landrace animals. In terms of the number of piglets at weaning, sows with standard previous lactation exceeded their counterparts with a reduced one by 3.1–3.6 %. The mass of the piglets at weaning also increased by 3.3 % in Large White and by 5.2 % in Landraces, with a relatively reduced standard previous lactation. The average daily gains of piglets were higher in Landraces – by 5.9 % and 3.5 % compared to Large Whites, depending on lactation duration. Most traits showed greater variability in Landrace animals. Thus, an increase in the duration of the previous lactation had a positive effect on the main reproductive indicators regardless of the breed. It was found that in Landrace sows, the correlations between reproductive and productive traits were stronger and more numerous than in the Large White breed. This indicates higher genetic variability and breeding potential of Landraces. In Large White sows, higher stability of litter retention was observed, which is an economically valuable trait. It was found that the duration of the previous lactation had a more pronounced effect on the reproductive performance of sows compared to breed.