Effects of Soybean Meal Fermented by Lactobacillus plantarum NX69 on Growth Performance and Intestinal Health of Nursery Pigs

The Intestinal system of nursery pigs is not fully matured and is easily disturbed by dietary composition and nutritional content. Probiotic-fermented feed has emerged as a beneficial dietary form for nursery pigs and is widely utilized in the livestock and poultry industries. However, there are limited reports regarding the effects of Lactobacillus plantarum-fermented feed on intestinal health and growth performance in nursery pigs. In this study, we investigated the effect of Lactobacillus plantarum NX69-fermented soybean by multi-omics approaches on intestinal health and growth performance in nursery pigs. The results demonstrated that NX69-fermented soybean meal increased small intestinal villus height, the villus height-to-crypt depth ratio (V/C), and the number of goblet cells per unit length. Additionally, it enhanced the mRNA of intestinal mucosal barrier factors ZO-1, Occludin, and Claudin in nursery pigs. Further research revealed that NX69-fermented soybean meal increased the diversity of the intestinal microbiota structure, elevated the abundance of core microbiota such as Alloprevotella, Prevotellaceae, and Megasphaera in the cecum, and increased the abundance of genera such as Megasphaera, Faecalibacterium, and Ruminococcus, which are known to produce short-chain fatty acids (SCFAs) in the cecum. Correlation analysis indicated that the core microbiota were positively correlated with intestinal physical barriers, including villus length and the V/C ratio, as well as with the mRNA level of intestinal mucosal barrier factors ZO-1, Occludin, and Claudin. Furthermore, they were positively correlated with differential metabolites such as Ginkgetin, Formiminoglutamic acid, Naringenin, and Hydroxyisocaproic acid. These findings suggest that NX69-fermented soybean meal can enhance the intestinal mucosal barrier in nursery pigs by increasing the abundance of core microbiota that produce SCFAs and then promoting intestinal health and improving growth performance, indicating promising application prospects.