196 Feeding and nutritional strategies to improve welfare of group-housed gestating sows

Abstract

Abstract Gestating sows in group-housing systems usually face two major welfare challenges: aggression when mixing with unfamiliar pen-mates and a lack of satiety due to restricted feeding. The two issues might be related because that hungry animals may be frustrated so that they may be more aggressive than animals that are in satiety. To restricted-fed gestating sows, one of the strategies to reduce aggression at mixing is to increase feed intake for a short period of time around mixing. Research showed that this strategy could reduce aggression among sows during feeding in competitive feeding systems, but had very limited effects on aggression during the initial period of mixing. Likewise, neither providing feed when moving sows in group-pens nor dividing the daily ration into multiple meals affected aggression caused by mixing. There is evidence that supplementation of an excessive amount of Tryptophan in the diet could reduce aggression in growing and finishing pigs. However, effects of dietary Tryptophan on reducing aggression among sows during mixing is less evident. Possibly, sows are more persistent in fighting for dominance hierarchy than young pigs. Although high fiber diets had limited effects on reducing aggression among sows at mixing, providing fermentable fibers in the diet could increase satiety in sows. Increasing satiety could reduce stereotypies, reduce aggression for maintaining dominance hierarchy, and increase resting time, which consequently will improve welfare of group-housed gestating sows.