“Porcine Digestible Peptides (Pdp) in Weanling Diets Improves Gut Barrier Function, Immune Response and Nutrient Transport in Nursery Pigs” 

Abstract Background : Porcine digestive peptides (PDP) have proven to be a valid substitute for other high-quality dietary protein sources for piglets, like spray-dried plasma (SDP), but knowledge about their influence on intestinal function is still scarce. This study was conducted to investigate the effects of PDP, SDP or a combination of both on growth performance and intestinal function of weaned pigs. Results : A total of 180 piglets (Trial 1) and 198 piglets (Trial 2) were used to evaluate the partial substitution of soybean ingredients with 2% SDP or 2% PDP (Trial 1), and with 3% SDP or the combination of 1% SDP and 2% PDP (SDP-PDP; Trial 2) during the pre-starter period (d0-14). A common commercial diet was offered up to day 35 in Trial 2. The effects on intestinal function were evaluated by quantifyingthe gene expression (56 genes in an Open Array Real-Time PCRPlatform) in jejunum and ileum samples obtained from piglets on d 14 after weaning (Trial 2).Piglets fed SDP, PDP and SDP-PDP had a higher body weight (BW), average daily gain (ADG) and feed efficiency (G:F) than the soybean controlon day 14 ( P < 0.05), but no differences were observed among groups at the end of starter phase (Trial 2). Ten genes in jejunum and five in ileum samples were differentially expressed among treatments ( P < 0.05). The highest expression was found in the SDP-PDP group. These genes are involved in the barrier function of intestinal cells,the immune response, mucosal nutrient transport, digestion and metabolization of oxidation products. Conclusion : The combination of SDP and PDP upregulated genes related to the intestinal functionwithout affecting growth performance. The underlying mechanisms that produced these effects are still unknown; however, protein hydrolysates might contain bioactive peptides that could be the cause.