It is not known if supplementation with functional amino acids (FAA) may mitigate the negative effects of intrauterine growth retardation seen in low birth weight (LBW) pigs. The objective was to determine the effects of birth weight category (BWC) and FAA supplementation during the postweaning period in Salmonella-challenged pigs. Thirty-two LBW (1.08 – 0.11 kg) and normal birth weight (NBW; 1.58 – 0.11 kg) pigs were assigned to a nursery feeding program at weaning (25 d) for 31 days in a 2 x 2 factorial arrangement. Factors were BWC (LBW vs. NBW) and basal (FAA–) or supplemented FAA profile (FAA+; Thr, Met, and Trp at 120% of requirements). At d 31, pigs were placed onto a common grower diet and, after a 7-d adaptation period, were inoculated with Salmonella Typhimurium (ST) and monitored for 7-d post inoculation.
Post-inoculation ADG was increased in NBW fed FAA+ compared to the other groups. There was no effect of FAA supplementation on rectal temperature or fecal shedding (P > 0.10). Salmonella shedding and translocation to spleen were lower in NBW-FAA+ compared to NBW-FAA- pigs (P < 0.05). Inoculation haptoglobin, superoxide dismutase, and colonic myeloperoxidase were increased in LBW-FAA- pigs (P < 0.05). Ileal alkaline phosphatase was decreased in LBW compared to NBW (P < 0.05).
Overall, the beneficial effects of FAA were dependent on birth weight category, with NBW pigs benefiting more from supplementation compared to LBW pigs. Therefore, functional amino acid supplementation represents a potential strategy to mitigate the effect of enteric disease challenges in normal birth weight, but not low birth weight pigs.
Can functional amino acids help low birth weight pigs in a Salmonella challenge? (full article)
