PSVI-17 - Supplemental Effects of Soy Protein Supplements Replacing Animal Protein Supplements on Growth Performance and Intestinal Health of Nursery Pigs

Abstract: This study evaluated the effects of soy protein supplements replacing animal protein on growth performance and intestinal health of nursery pigs. Soy protein supplements included processed soybean meal processed after ethanol extraction, enzyme hydrolysis, and fermentation. Forty-eight newly weaned pigs (6.6 ± 0.3 kg BW) were allotted to 4 treatments in a RCBD with initial BW and sex as blocks. Pigs were fed for 39 d in 3 phases (P1/2/3 for 7/13/19 d, respectively). Dietary treatments were CON (basal diet with fish meal 4/2/1%, poultry meal 10/8/4%, and blood plasma 4/2/1% for P1/2/3, respectively), SPC, ESBM, and FSBM (basal diets with soy protein concentrate (SPC), enzyme treated soybean meal (ESBM), and fermented soybean meal (FSBM), replacing 1/3, 2/3, 3/3 animal protein supplements in P1, P2, P3, respectively). Titanium dioxide (0.4%) was added to diets as indigestible marker from d 32. Growth performance was recorded by phase. Pigs were euthanized on d 39 to collect samples to measure intestinal health and apparent ileal digestibility (AID) of nutrients. Data were analyzed using SAS 9.4. The SPC tended to increase (P = 0.060) Ki-67⁺ crypt cells (26.7 to 29.0%), and decreased (P < 0.05) AID of EE (66.2 to 52.2%) without affecting growth performance and fecal scores. The ESBM tended to decrease (P = 0.098) protein carbonyls (1.93 to 1.38 nmol/mg of protein) in the jejunal mucosa without affecting growth performance. The FSBM increased (P < 0.05) TNF-α (0.39 to 0.72 pg/mg of protein) in the jejunal mucosa without affecting growth performance. Collectively, soy protein supplements obtained from soybean meal by ethanol extraction, enzyme hydrolysis, and fermentation can partly replace animal protein supplements without affecting the growth performance with minor impacts on intestinal health of nursery pigs.