FIG 2.

Expression of Bu-1α, IgA, IgM, and IgY is associated with the gut microbiota during the development of the bursal B cell. (A) Bu-1α-positive lymphoid follicle. (B) IgA-positive lymphoid follicle. (C) IgY-positive lymphoid follicle. (D) IgM-positive lymphoid follicle on different days. Ten random fields per specimen were analyzed with Image Pro-Plus V.6, and the mean fluorescence intensity per power field was recorded. Data are means ± SEM (NS, not significant) (n = 6). (E to G) Three alpha diversity scores based on the Chao1 index, the number of observed species, and the Shannon index. (H) Principal-coordinate analysis of cecal microbial beta diversity based on Bray-Curtis dissimilarity for each age group (n = 6). (I and J) Spearman correlations among the gut microbiota, Bu-1α, and three immunoglobulins at the phylum (I) and genus (J) levels. Spearman’s correlation coefficient was calculated between the microbial composition and Bu-1α, IgA, IgY, and IgM. A P value of <0.05 and a correlation of >0.6 were considered statistically significant (n = 6). *, P < 0.05; **, P < 0.01.