Amino acids with Corynebacterium glutamicum cell mass can replace crystalline amino acids for its postbiotic effects on immune and oxidative stress status in the jejunum of nursery pigs

Costs of producing amino acids (AA) can be reduced by eliminating purification processes to remove Corynebacterium glutamicum cell mass (CGCM) used for AA production. The objective was to evaluate the effects of supplemental Lys, Thr, and Val with CGCM as an alternative source of crystalline AA (CAA) on intestinal health and growth performance of nursery pigs. Sixteen pigs (initial body weight = 7.1 ± 0.4 kg) were allocated to 2 dietary treatments (n = 8) in a randomized complete block design and fed for 14 days. Experimental diets included either CAA or AA with CGCM (AAC) as AA sources. The use of AAC provided 5.8 g/kg of CGCM in the experimental diet. On day 14, pigs were euthanized to collect intestinal tissues and mucosa. Mucosal tumor necrosis factor-α in the jejunum of pigs fed a diet with AAC was less (P = 0.012) than that with CAA, whereas mucosal immunoglobulin G in the jejunum of pigs fed a diet with AAC was greater (P < 0.001) than that with CAA. Mucosal interleukin-6 (P = 0.062) and protein carbonyl (P = 0.082) in the jejunum of pigs fed a diet with AAC tended to be less than that with CAA. A replacement of crystalline Lys, Thr, and Val by AAC did not change blood profiles, jejunal morphology, and growth performance of pigs. In conclusion, replacing CAA with AAC reduced pro-inflammatory cytokines and oxidative damage products in the jejunal mucosa of pigs, without compromising growth performance.