Review of yeast culture concerning the interactions between gut microbiota and young ruminant animals

Microorganisms inhabit the gastrointestinal tract of ruminants and regulate body metabolism by maintaining intestinal health. The state of gastrointestinal health is influenced not only by the macro-level factors of optimal development and the physiological structure integrity but also by the delicate equilibrium between the intestinal flora and immune status at the micro-level. Abrupt weaning in young ruminants causes incomplete development of the intestinal tract resulting in an unstable and unformed microbiota. Abrupt weaning also induced damages to the microecological homeostasis of the intestinal tract, resulting in the intestinal infections and diseases, such as diarrhea. Recently, nutritional and functional yeast culture has been researched to tackle these problems. Herein, we summarized current known interactions between intestinal microorganisms and the body of young ruminants, then we discussed the regulatory effects of using yeast culture as a feed supplement. Yeast culture is a microecological preparation that contains yeast, enriched with yeast metabolites and other nutrient-active components, including β-glucan, mannan, digestive enzymes, amino acids, minerals, vitamins, and some other unknown growth factors. It stimulates the proliferation of intestinal mucosal epithelial cells and the reproduction of intestinal microorganisms by providing special nutrient substrates to support the intestinal function. Additionally, the β-glucan and mannan effectively stimulate intestinal mucosal immunity, promote immune response, activate macrophages, and increase acid phosphatase levels, thereby improving the body's resistance to several disease. The incorporation of yeast culture into young ruminants' diet significantly alleviated the damage caused by weaning stress to the gastrointestinal tract which also acts an effective strategy to promote the balance of intestinal flora, development of intestinal tissue, and establishment of mucosal immune system. Our review provides a theoretical basis for the application of yeast culture in the diet of young ruminants.

Spatial and temporal organization of jejunal microbiota in goats during animal development process

AIMS

This research aimed to investigate the temporal bacterial colonization relating to non-rumination, transition and rumination phases, together with the spatial organization of microbial community in the jejunal mucosa and digesta of goats.

METHODS AND RESULTS

This study explored the colonization programme of the jejunal microbiota by employing 16S rRNA amplicon sequencing. The colonization pattern of jejunal bacterial community exhibited an age- and gut region-dependent progression during animal development process. Approximately 268 bacterial signatures contributed to the discrimination between gut regions, with Lactobacillus, Ruminococcus, Eubacterium and Clostridium_sensu_stricto were enriched in the jejunal digesta, and Bacteroides and unclassified bacteria were enriched in the jejunal mucosa. Intriguingly, a shift from Lactobacillus to Butyrivibrio, Eubacterium and Ruminococcus after d 20 was observed for jejunal digesta. In mucosa, Bifidobacterium, Corynebacterium, Faecalibacterium and Roseburia increased with age (P < 0·05) while Arcobacter, Bacteroides and Porphyromonas peaked at d 10.

CONCLUSIONS

The jejunal bacterial community was settled after solid starter provision, which may mark the potential boundary of a timeframe for intervention in goats. The spatial heterogeneity highlighted the complicacy of ecological niches during manipulation of gut microbiota.

SIGNIFICANCE AND IMPACT OF THE STUDY

The present study extended the understanding of microbial programming and niche specific in the jejunum among different life stages and the basal cognition of persistent enhancement of nutrient utilization and decline of enteric diseases in ruminants.

Rhubarb Supplementation Promotes Intestinal Mucosal Innate Immune Homeostasis through Modulating Intestinal Epithelial Microbiota in Goat Kids

The abuse and misuse of antibiotics in livestock production pose a potential health risk globally. Rhubarb can serve as a potential alternative to antibiotics, and several studies have looked into its anticancer, antitumor, and anti-inflammatory properties. The aim of this study was to test the effects of rhubarb supplementation to the diet of young ruminants on innate immune function and epithelial microbiota in the small intestine. Goat kids were fed with a control diet supplemented with or without rhubarb (1.25% DM) and were slaughtered at days 50 and 60 of age. Results showed that the supplementation of rhubarb increased ileal villus height (P = 0.036), increased jejujal and ileal anti-inflammatory IL-10 production (P < 0.05), increased jejunal and ileal Claudin-1 expression at both mRNA and protein levels (P < 0.05), and decreased ileal pro-inflammatory IL-1β production (P < 0.05). These changes in innate immune function were accompanied by shifts in ileal epithelial bacterial ecosystem in favor of Blautia, Clostridium, Lactobacillus, and Pseudomonas, and with a decline in the relative abundance of Staphylococcus (P < 0.001) when rhubarb was supplemented. Additionally, age also affected (P < 0.05) crypt depth, cytokine production, Claudin-1 expression and relative abundances of specific genera in epithelial bacteria. Collectively, the supplementation of rhubarb could enhance host mucosal innate immune homeostasis by modulating intestinal epithelial microbiota during the early stages of animal development.