Oral administration of N-carbamylglutamate might improve growth performance and intestinal function of suckling piglets

The objective of this study was to investigate the effects of oral N-carbamylglutamate (NCG) administration on intestinal digestive enzymes, microbiota population and immunity under physiological condition in newborn piglets. A total of 48 1-d-old piglets (sow reared) were allotted, based on the initial body weights (1.57±0.04 kg), into 4 treatments (12 piglets/group): (1) 0.52 g/kg body weight (BW) l-Alanine (control), (2) 0.31 g/kg BW l-Arginine·HCl (arginine), (3) 0.52 g/kg BW l-Alanine plus 50 mg/kg BW NCG, and (4) 0.52 g/kg BW l-Alanine plus 100 mg/kg BW NCG. The supplement were offered twice daily for 14 d. At d 7 and d 14, 6 piglets from each group were killed. Piglets supplemented with 50 mg/ kg BW NCG had increased average daily gain during days 1-14 after birth and jejunal mucosal lactase activity on d 7 compared with piglets supplemented with control, arginine and 100 mg/kg BW NCG groups. Serum concentrations of arginine, glutamate, citrulline and ornithine in arginine, 50 and 100 mg/kg BW NCG groups were markedly increased at d 7 and 14, in comparison with the control group (P<0.05). Moreover, the number of cecal Lactobacillus spp. in both NCG groups was higher than the control and arginine groups at d 14 (P<0.05). Serum IgA (P=0.05) and ileal sIgA (P=0.08) concentrations in the 50 mg/kg BW NCG and arginine groups were higher than those in the control and 100 mg/kg BW NCG groups at d 14. In conclusion, oral administration of 50 mg/kg BW NCG to newborn piglets improved growth performance, increased the endogenous synthesis of arginine and arginine family of amino acids, jejunal lactase activity and cecal Lactobacillus spp. numbers, and stimulated secretion of ileal sIgA.