Prophylactic Enrichment of Sow Milk and Intestinal Mucosa of Piglets By Supplementation of Arachidonic and Eicosapentaenoic Acid to Sows during Lactation

Long-chain polyunsaturated fatty acids have been shown to improve intestinal barrier function and recovery following intestinal injury in young pigs. The objectives of this study were to determine dose and duration of arachidonic acid (ARA) and eicosapentaenoic acid (EPA) supplementation required to efficiently enrich sow milk and intestinal tissue of suckling piglets, and to determine its effects on pre- and post-weaning performance. Sows (n=60) were assigned to a RCBD with 5 dietary treatments, consisting of: control (palm kernel oil), 72.5 and 145 g/d of ARA, and 72.5 and 145 g/d of EPA. Sows were supplemented for 14 d prior to weaning with 343 g of lipid mixtures containing the targeted concentrations of ARA and EPA once daily. Concentrations of ARA in milk increased linearly (P<0.001) with ARA supplementation on d 6 (0.53, 3.50, and 6.14%, for 0, 72.5, and 145 g/d ARA, respectively) and d 13 (0.50, 3.50, and 8.12%), and were greater (P<0.001) on d 13 compared to d 6 for the 145 g/d ARA treatment. Concentrations of ARA in intestinal mucosa of piglets, measured after 7 and 14 d of supplementation in lactation and 7 d post-weaning, linearly increased (P<0.01; 9.59, 12.59, and 13.02%) with increasing dietary ARA. Mucosal ARA concentrations increased during lactation, but decreased after pigs were weaned (quadratic, P=0.006; 11.42, 13.81, and 9.97% for d 7, 14, and 7 d post-weaning, respectively). Milk EPA concentrations linearly increased (P<0.01) with EPA supplementation on d 6 (0.05, 4.45, and 5.27%) and d 13 (0.02, 3.07, and 7.24%), and tended (P=0.07) to be higher on d 13 compared to d 6 when 145 g/d of EPA was fed. Similarly, EPA content of mucosa increased linearly (P<0.001) with dietary supplementation on d 7 (0.15, 2.38, and 6.59%), d 14 (0.16, 3.14, and 5.55%) and 7 d after weaning (0.06, 1.50, and 2.33%). Concentrations of EPA were lower (P<0.05) 7 d after weaning compared to d 14 for 72.5 g/d EPA and d 7 and 14 for 145 g/d EPA. Piglets (n=441) from sows fed control and 72.5 g/d EPA were 10% heavier at weaning and had 18% greater ADG (P<0.05) than pigs from sows fed 145 g/d ARA, but post-weaning performance was unaffected. Supplementation of sows with ARA and EPA increased milk concentrations progressively, which directly increased ARA and EPA profiles in piglet intestinal mucosa. However, intestinal enrichment did not affect post-weaning and overall pig performance.