LAUSR

Abstract Background Qing Chang oral liquid (QOL) is a veterinary drug, which mainly composed of Artemisiae annuae herba, Dichroae radix, Agrimonia pilosa and Sanguisorbae radix. Objectives This study aims to explore the effect of Qing Chang Oral Liquid (QOL) on the treatment effect of artificially infected chicken coccidiosis and to the cellular immunity. Methods Healthy Roman chickens were randomly divided into five groups: blank group, model group, QOL high‐, medium‐ and low‐dose groups. All the groups were orally administered with 1 × 104 sporulated oocysts (except the blank group). After 5 days of oral administration, the high‐, medium‐ and low‐dose groups of QOL were added to the drinking water at 2.4, 1.8 and 1.2 ml/kg, respectively. The blank and model groups were fed normally, and this experiment lasted for 7 days. The clinical signs were observed, and the relative weight gain, survival rate, cecum lesion score and oocyst value were measured to evaluate the effect of QOL. Meanwhile, the peripheral blood T‐lymphocyte subsets and cecal IL‐2, IL‐17, IFN‐γ mRNA expression were detected by flow cytometry and fluorescent quantitative PCR. Results The chickens in the model group were in poor mental state, gathered together, had loose stools or bloody stools and had less food intake and less exercise. The chicken mental state improved, the food intake and drinking water increased, and the faeces are normal in the high‐, medium‐ and low‐dose groups, especially in the high‐dose group, the anti‐coccidial indexes were up to 173.08. No significant differences were observed (p > 0.05) in the peripheral blood CD3+, CD3+CD4+ between the experimental groups. Compared with the blank group, there were different degrees of increase in each dose drug group of the cecal IFN‐γ, IL‐2 and IL‐17 mRNA expression, but the high‐dose group was significantly reduced compared with the model group (p < 0.01), but there was no significant difference (p > 0.05). Conclusions This study suggests that QOL has positive anti‐coccidial effect but has no obvious effect on the cellular immunity.