Effect of fecal microbiota transplantation on early intestinal immune function and histomorphology of immune organs in chicks.

The intestinal microbiota drives the maturation of the immune system, which is essential for maintaining lifetime homeostasis. Whether fecal microbiota transplantation can promote the development of the immune system in chicks? On days 1, 3, and 5, the post-hatch Hy-line Brown chicks were treated with fecal suspension from breeding hens. Intestinal length, blood biochemical indicators, the morphology of immune organs, and intestinal immunity-related indicators were focused on days 7 and 14. Short-chain fatty acids were determined by gas chromatography. We discovered that fecal microbial transplantation significantly increased the area of the follicles and medulla from the bursa of Fabricius, as well as the area of the medulla, cortex, and both ratios from the thymus on 14 d, the concentration of butyric acid in feces, the levels of immunologically active substances (transforming growth factor-ß, interleukin 10, forkhead box protein P3, G-Protein Coupled Receptor 43, immunoglobulin A, etc.) in serum or the intestine, and the number of goblet cells. Correlation analysis indicated that short-chain fatty acids, as metabolites of the gut microbiota, were correlated with intestinal immunity. In short, fecal microbiota transplantation regulated early intestinal immunity, which provided the possibility for the processing and utilization of gut microbiota as germplasm resources. IMPACT STATEMENT: Modern management of eggs causes the normal vertical transmission of microbiota from hens to be significantly reduced. The risk of environmental threats to newborn chicks is raised. The microbial community helps to mature the immune system of chicks and protect them from pathogen invasion. We still have doubts about whether transplanting the microbiota can regulate gut immunity. Using the gut microbiota of hens as an excellent resource to improve the immunity of chicks may provide new ideas for the development of the poultry industry.

Donor selection for fecal bacterial transplantation and its combined effects with inulin on early growth and ileal development in chicks.

AIMS: To select the best donor and investigate its combined effects with inulin on growth performance, and ileal health of chicks. METHODS AND RESULTS: The chicks (Hy-line Brown) were treated with fecal microbiota suspension from different breeder hens to select the best donor. Treatment with fecal microbiota transplantation (FMT) alone or in combination with inulin resulted in improvement in gut microbiome in chicks. The organ indexes were improved on day 7, especially the bursa of fabricius index (P < 0.05). On day 14, immune performance, ileal morphology, and barrier were improved, and simultaneously, the concentration of short-chain fatty acids was also increased. In addition, for the expression of ileal barrier-related genes, Anaerofustis and Clostridium were positively correlated with them (P < 0.05), Blautia, Prevotella, Veillonella, and Weissella showed a negative correlation (P < 0.05), and RFN20 showed a positive correlation with gut morphology (P < 0.05). CONCLUSION: Combination of homologous FMT and inulin promoted early growth and intestinal health of chicks.

Maternal effects drive intestinal development beginning in the embryonic period on the basis of maternal immune and microbial transfer in chickens.

BACKGROUND: Nutrition drives immunity and health in animals, and maternal immunity benefits offspring. In our previous study, a nutritional intervention strategy was found to promote the immunity of hens, which subsequently improved immunity and growth in offspring chicks. Maternal effects clearly exist, but how are mothers' immune advantages transferred to their offspring, and how do they benefit them? RESULTS: Here, we traced the beneficial effects back to the process of egg formation in the reproductive system, and we focused on the embryonic intestinal transcriptome and development, as well as on maternal microbial transfer in offspring. We found that maternal nutritional intervention benefits maternal immunity, egg hatching, and offspring growth. The results of protein and gene quantitative assays showed that the transfer of immune factors into egg whites and yolks depends on maternal levels. Histological observations indicated that the promotion of offspring intestinal development begins in the embryonic period. Microbiota analyses suggested that maternal microbes transfer to the embryonic gut from the magnum to the egg white. Transcriptome analyses revealed that offspring embryonic intestinal transcriptome shifts are related to development and immunity. Moreover, correlation analyses showed that the embryonic gut microbiota is correlated with the intestinal transcriptome and development. CONCLUSIONS: This study suggests that maternal immunity positively influences offspring intestinal immunity establishment and intestinal development beginning in the embryonic period. Adaptive maternal effects might be accomplished via the transfer of relatively large amounts of maternal immune factors and by shaping of the reproductive system microbiota by strong maternal immunity. Moreover, reproductive system microbes may be useful resources for the promotion of animal health. Video Abstract.