Dietary nucleotides influences intestinal barrier function, immune responses and microbiota in 3-day-old weaned piglets.

Nucleotides (NTs) play a pivotal role in the growth and development of the intestine. This study aimed to evaluate the effects of nucleotides supplementation on the intestinal barrier function, immune responses and microbiota in 3-day-old weaned piglets. Ninety-six piglets weaned at 3-days after birth were randomly assigned to 2 treatments (6 replicates/treatment, 8 piglets/replicate) according to the average body weight. The dietary treatments consisted of the control (CON; fed a basal artificial milk) and nucleotides groups (NT; fed a basal artificial milk with 0.035 % nucleotides, the contents of CMP, UMP, AMP, GMP, and IMP were 1:1:1:1:1, respectively). Diarrhea rates were recorded, and blood and intestinal samples were collected on day 35 of the piglets. The current study showed that NTs supplementation tended to decrease the diarrhea rate of weaned piglets (P < 0.10). NTs increased villus height and the villus height-to-crypt depth (V/C) ratio in the ileum (P < 0.05). Dietary NTs up-regulated protein expression of ZO-1 in ileal mucosa (P < 0.05), and the protein expression of Occludin tended to increase. Furthermore, NTs up-regulated the mRNA expression of Mucin (MUC)2, while the mRNA expression of MUC4 was down-regulated in the ileal mucosa (P < 0.05). Besides, supplementation with NTs increased the ileal mucosa genes expression of IL-21, INF-γ, IL-10, IL-4, IL-6 and TNF-α (P < 0.05). Furthermore, dietary NTs increased the protein expression of NF-κB, IL-6 and TNF-α (P < 0.05), and the proteins expression of Occludin and p-NF-κB tended to be up-regulated in the ileal mucosa (P < 0.10). Furthermore, NTs supplementation increased short chain fatty acid in the colonic (P < 0.05). And NTs supplementation reduced the Firmicutes/Bacteroidota ratio in the colon, at the genus level, NTs enriched the relative abundance of Prevotella, Faecalibacterium and Olsenella (P < 0.05). These data indicate that NTs could increase the villus height, increase the V/C, regulate the expression of tight junction protein and mucin, improve the intestinal barrier of piglets, regulate the secretion of cytokines, improve the biological immunity, increase the abundance of beneficial bacteria, and thus reduce the diarrhea of piglets.

Rumen microbiota responses to the enzymatic hydrolyzed cottonseed peptide supplement under high-concentrate diet feeding process.

In current dairy production, dietary energy is always excessively provided with a high-concentrate diet feeding to improve milk production. However, this feeding practice disturbed the rumen microbial ecosystem and the balance between ruminal energy and nitrogen, resulting in decreased nutrient fermentability, which in turn declined the milk yield of dairy cows. Therefore, supplementation of dietary degradable nitrogen may be helpful for high dairy production. In this study, we evaluated the regulatory effects of easily utilized enzymatic hydrolyzed cottonseed peptide (EHP) supplements on rumen microbiota communities and rumen nutrient fermentability under high-concentrate feeding. For this purpose, a gradient concentrate of EHP (from 0.2 to 1.0%) was added to the high-concentrate basal substrates for an in vitro experiment. Each treatment contained three replicates, with three bottles in each replicate. Rumen fermentable parameters included microbial protein content, volatile fatty acids, and ammonia-N; the rumen nutrient degradability of dry matter, crude protein, neutral detergent fiber, acid detergent fiber, ether extracts, calcium, and phosphorus were further investigated after in vitro fermentation for 72 h. Then, rumen microbiota communities and their correlation with ruminal fermentation parameters and rumen nutritional degradability were analyzed to understand the regulatory mechanism of the EHP supplements on rumen fermentability. Results indicate that treatment with 0.6% of EHP supplements had the highest content of acetate, butyrate, and neutral detergent fiber degradability among all treatments. Furthermore, EHP supplements significantly increased the relative abundance of rumen cellulose and starch-degrading bacteria such as Ruminococcus, Bifidobacterium, and Acetitomaculum, and the high nitrogen utilizing bacteria Butyrivibrio and Pseudobutyrivibrio, which may further promote the rumen carbohydrate and nitrogen metabolism. In summary, supplementation of easily degraded small peptides helps reestablish rumen energy and nitrogen balance to promote the rumen fermentable functions and nutritional degradability under high-concentrate diet feeding circumstances. These findings may further promote dairy production.