Fecal virus transplantation has more moderate effect than fecal microbiota transplantation on changing gut microbial structure in broiler chickens

ABSTRACT: Growing evidence of fecal microbiota transplantation (FMT) and fecal virus transplantation (FVT) provides a possibility to regulate animal health, whereas little is known about the impact of the 2 methods. This study aimed to investigate the effects of gut microbes on jejunal function in healthy broiler chickens, with the objective of establishing a theoretical basis for the application of FMT and FVT. Cecal feces from 28-day-old AA broilers were collected to prepare gavage juice for FMT and FVT. FMT for Group FM, FVT for group FV and PBS gavage for group CON, continuously treated for 6 days start at 5-day-old chicks. Samples were collected at d 11 and d 21. The results showed that the treatment d 2 and the overall fecal score in treatment groups were significantly lower than CON group (P < 0.05). The jejunum morphology showed that FMT increased crypt depth, decreased villus height, V/C (P < 0.05) and FVT increased villus height (P < 0.05) at d 11. At d 21, villus height and crypt depth significantly higher (P < 0.05) in group FM and group FV. The expression of Claudin1, Occludin, ZO2, and Muc2 in the FV group was significantly increased (P < 0.05) at 11-day-old. FMT increased the secretion of sIgA at 11-day-old, and this influence lasted up to 21-day-old (P < 0.05). At 11-day-old, the expression of b0+AT of basic amino acid transport carrier and chymotrypsin activity (P < 0.05) had a significant correlation. At 21 d of age, FVT significantly increased the expression of PepT1 and SGLT1 (P < 0.05). At 11-day-old, FM group showed significantly higher faith pd index (P = 0.004) and Shannon index (P = 0.037), and separated from FV and CON according to PCoA. Among differentiating bacteria, Bacteroides significantly enriched (P < 0.05) in group FM, which positively correlated with the expression of ZO2, Muc2, Occludin, and Claudin1; R_Ruminococcus, L_Ruminococcus, Butyricicoccuss significantly enriched (P < 0.05) in group CON, which significantly higher than processing groups, R_Ruminococcus and L_Ruminococcus negatively correlated with the expression of Occludin (P < 0.05), and R_Ruminococcus, Butyricicoccus negatively correlated with the expression of Claudin1 (P < 0.05). At 21-day-old, PCoA based on Bray-Curtis shows that microbes taxa of 3 groups are isolated with each other and treatment groups were significant different with CON group based on Unweighted UniFrac and weighted UniFrac. The expression of PepT1 was significantly negatively (P < 0.05) correlated with Ruminococcus, and the expression of sIgA was significantly negatively (P < 0.05) correlated with Parabacteroides. In conclusion, FMT regulated intestinal flora rapidly, while it had little effect on intestinal function and a higher potential damaging risk on jejunal. FVT regulated intestinal flora structure softer, improved tight junction expression, but the mechanism of action needs further exploration.