Studies on the relationship between intestinal flora and cecal coccidiosis in chicken.

The bacteriological and histopathological changes in the ceca of young chickens after being infected with sporulated oocysts of Eimeria tenella were investigated. Lactobacilli and bifidobacteria showed remarkable decrease in number on the 5th day after infection, when shizont and gametocyate came to appear, and destruction of mucosa along with severe haemorrhaging was noticed. Other predominant bacteria like bacteroidaceae, catenabacteria and peptostreptococci showed only moderate and temporal decrease in number during the infection. Clostridium perfringens prolifereated after the 5th day post infection following the decline of lactobacilli and bifidobacteria. Proliferation of clostridia was so intense that the number was almost million times greater than that of the uninfected chicken at its peak on the 7th day after infection. Enterobacteria also showed a moderate but persistent increase in number. Most bacteria came to the normal population on the 10th day after infection. As for lactobacilli, bifidobacteria, clostridia and enterobacteria, the disturbances were still noticeable on the 17th day after injection. Antagonism between proliferated bacteria (clostridia and enterobacteria) and lactic acid bacteria (lactobacilli and bifidobacteria) whose intensity is suppose to be related to the cecal mucosa is suggested during cecal coccidiosis in chickens.