PSXIII-23 Dietary glutamine, glutamate, and aspartate supplementation improves morphology and intercellular junction of small intestine in piglets

Abstract

Abstract Weaning-stress decreases the digestive and absorptive capacity of small intestine in piglets, resulting in reduction in energy intake for intestine cells and defects in epithelial structure. As glutamine (Gln), glutamate (Glu), and aspartate (Asp) are major energy sources for small intestine; thus, this study was conducted to test the hypotheses that supplementation with Gln, Glu, and Asp in diets will improve the intestinal morphology and tight junction in weaning piglets. 198 weaned piglets were assigned to the following treatments: i) Control (Basal diet + 1.59% L-Alanine); ii) T1 (Basal diet + 1% L-Glutamine + 0.5% L-Glutamate + 0.1% L-Aspartate); iii) T2 (Low energy diet + 1% L-Glutamine + 0.5% L-Glutamate + 0.1% L-Aspartate). The small intestinal samples were obtained on 5 or 21-day-post-weaning. The results showed that basal dietary supplementation with Gln, Glu, and Asp in basal diet improved the final body weight (BW), average daily gain (ADG) of piglets on 21-day of post-weaning. Supplementation with Gln, Glu, and Asp in diet with low energy decreased the villus height and crypt depth in ileum of piglets on 5-day-post-weaning, but increased villus height and goblet cell number in jejunum on 21-day post-weaning compared with those in control group. On 5-day-post-weaning, high mRNA levels of voltage-gated potassium (Kv) 1.1 in ileum and Kv 1.5 in jejunum were observed in T 1 and T 2 groups, respectively. Other indicators were higher than those in control piglets on day 5 or 21 post-weaning, including protein abundances of claudin-1, laudin-3 and occluding, and the percentage of proliferating cell nuclear antigen (PCNA)-positive cells in jejunum and ileum in T 1 or T 2 groups. Collectively, these findings indicated that Gln, Glu, and Asp can alleviate the intestinal barrier injury in piglets induced by weaning stress even under low energy diet.