Changes of cecal microflora in chickens following Eimeria tenella challenge and regulating effect of coated sodium butyrate.

Eimeria tenella, one of the most important parasitic protozoa in the genus Eimeria, is responsible for chicken caecal coccidiosis resulting in huge economic losses to poultry industry. The present study investigated the changes in caecal microflora of E. tenella-infected chickens and the regulating effect of coated sodium butyrate, a potential alternative to antibiotics. Using high-throughput sequencing of 16S rRNA V3-V4 region of bacteria we found significant changes in caecal microflora of E. tenella-infected chickens indicated by an increase of Firmicutes (mainly Ruminococcaceae, Lachnospiraceae and vadin BB60) and Proteobacteria (mainly Enterobacteriaceae) and a decrease of Bacteroidetes (predominantly Bacteroidaceae). Inclusion of coated sodium butyrate in the diet of chickens per se had no significant effect on caecal microflora of normal healthy chickens but significantly prevented the increase in Firmicute abundance and decrease of Bacteroidetes abundance in E. tenella-infected birds. No significant changes to caecal microflora were observed at the phylum level between control and E. tenella-infected birds given coated sodium butyrate. In conclusion, our results show that coated sodium butyrate can balance the disorders of cecal microflora caused by E. tenella; thus, it can be a useful supplement for the control of avian coccidiosis.