Effects of Different Iron Supplements on Reproductive Performance and Antioxidant Capacity of Pregnant Sows as Well as Iron Content and Antioxidant Gene Expression in Newborn Piglets

SIMPLE SUMMARY: Anemia in piglets is a common problem in piglet production. In this experiment, three different iron additives were used in pregnant sow feed for comparison. The results revealed that adding iron supplements can improve the antioxidant capacity of sows, and lactoferrin and heme iron can improve the iron nutrition and antioxidant capacity of piglets. This study should help improve the reproductive performance of sows, prevent iron deficiency anemia in piglets, and improve disease resistance. ABSTRACT: To improve the reproductive performance of sows and the iron nutrition of newborn piglets, we studied the effects of dietary iron on reproductive performance in pregnant sows as well as antioxidant capacity and the visceral iron content of sows and newborn piglets. Forty pregnant sows were divided into four groups, the iron deficiency group (Id group) was fed a basic diet while sows in the treatment groups were fed diets supplemented with 200 mg/kg lactoferrin (LF group), 0.8% heme-iron (Heme-Fe group), or 500 mg/kg iron-glycine complex (Fe-Gly group). The results indicated that (1) different sources of iron had no significant effect on litter size, live litter size, and litter weight of sows; (2) the three additives improved iron nutrition in newborn piglets, with LF and Heme-Fe having better improvement effects; and (3) the addition of different iron sources improved the level of serum antioxidant biochemical indexes of sows and newborn piglets, and it can have an effect on gene level, among which lactoferrin has the best effect. Thus, adding LF, Heme-iron, or Fe-Gly to the diet of sows during the second and third trimester of gestation can improve the antioxidant capacity of the sows. The supplementation of LF in pregnant sow diets can also improve the antioxidant capacity and the iron nutrition of newborn piglets, with better additive effects than in Heme-Fe and Fe-Gly.