Effects of "Shi Ying Zi" powder and osthole on immune and antioxidant function of Eimeria tenella-infected broilers

"Shi Ying Zi" powder is a traditional Chinese herbal formula for preventing and treating coccidiosis. In our previous studies, it showed anticoccidial effects and exhibited the potential to control Eimeria tenella infection. In this research, we evaluated the antioxidation and immune effect of "Shi Ying Zi" powder and its effective active ingredient osthole on coccidiosis-infected broilers to explore the mechanism of its anticoccidial effect. We analyzed changes in the antioxidant index, the pathological changes in cecum, immune index of serum and composition of cecal flora. The results showed that the use of "Shi Ying Zi" powder and osthole alleviated the pathological changes in the cecum, spleen and bursa of Fabricius, upregulated the spleen and bursal weigh index. "Shi Ying Zi" powder of 10 g/kg effectively rocovered the contents of interleukins and immunoglobulin in serum. Osthole increased the proportion of Firmicutes, Actino-bacteria and Lactobacillus in the cecum. In summary, "Shi Ying Zi" powder and osthole have anticoccidial effects, and they also can active the immunity, antioxidant functions and upregulate the beneficial bacteria population in Eimeria tenella-infected broilers.