Abstract: The purpose of our research was to explore the effects of sulfated yeast glucan (sGSC) on the prevention and treatment of artificial Eimeria tenella disease in chickens. In this study, cage feeding was used to randomly divide 200 chickens into group A (4 mg·kg^-1), group B (16 mg·kg^-1), group C (64 mg·kg^-1), group D (infection control group) and group E (healthy control group). Three days before the coccidiosis infection, the chickens of groups A, B, and C were given the above-mentioned concentrations of sGSC by body weight every day, and the chickens of groups D and E were fed with reverse osmosis water (RO water) until the end of the experiment. During the experiment, the clinical symptoms, and bloody stools of each group of chickens were observed and recorded, the feces from 5 to 6 days after infection were collected and the number of oocysts per gram of feces was detected. All chickens were killed on the 7th day after infection, and the organ index was calculated; The diversity of the microbial community in the cecum of the chicken was studied through the Illumina sequencing platform. The results showed that： 1) Compared with group D, the cecal swelling of the chickens in each sugar group was significantly reduced, and their intestinal contents and bleeding were significantly reduced. Compared with the weight of the chickens in the E group, the weight of the A and D groups was significantly reduced (P<0.05), however, the body weight of chickens in group B and C were increased to the level of group E, and there was no significant difference with the body weight from chickens in group E (P>0.05); the number of oocysts excreted by chickens in group B and C was compared with that in group D, and there have a significant reduction in group B and C compared with group D, but there was no statistical difference (P>0.05); The thymus index of chickens in group A increased significantly (P<0.05), and the liver index was also significantly improved (P<0.05); 2) Analysis of the cecal flora found that sGSC increased the relative abundance of Veillonellaceae and Lactobacillaceae in the cecum. The relative abundance of Enterococcaceae has been reduced. The results showed that sGSC could reduce the damage caused by Eimeria tenella infection to chickens, and the effects were more obvious with the increase of sGSC dose. In short, sGSC has good anti-coccidial effects, and has beneficial regulatory effects on the intestinal flora of chickens infected with coccidia. In conclusion, sGSC has a certain anti-coccidial effect and has beneficial regulatory effect on the intestinal flora of chickens infected with coccidia.

Key words: sulfated yeast glucan, coccidia, intestinal bacteria, overuse of drugs