Abstract: In order to verify the effect of Manhuning oral liquid on treating chronic respiratory disease in chickens,the 21-day-old Yellow broiler chickens were randomly divided into six groups (n=30) including high-dose group,middle-dose (equivalent to the recommended dose) group,low-dose group of Manhuning oral liquid and Zhenchuan power group,model group,the control group. The chickens in each group were artificially infected with Mycoplasma gallisepticum except to the control group. The chickens in each administration group were given the drug continuously for 7 days and then all of the chickens were observed for 14 d. The clinical efficacy,average weight gain and pathological changes were observed and evaluated,respectively. The results showed that the high-dose and middle-dose group of Manhuning oral liquid had an apparent effect on infected chickens and the serum Mycoplasma antibody-positive rate could be apparently reduced,while the rate of airbag injury reduction could be both above 90% and the positive rates of chickens' Mycoplasma antibody were 10% and 20%. Also the average weight gains were 596.1 and 661.3 g. In Zhenchuan power group,the rate of airbag injury reduction (82.5%) and the average weight gain were lower than the high-dose group and middle-dose group of Manhuning oral liquid,while the serum Mycoplasma antibody-positive rate (30%) was higher. The results showed that Manhuning oral liquid had good effect on prevention of the chronic respiratory disease in chicken,and its effect was better than the Zhenchuan power.

Key words: Manhuning oral liquid; chronic respiratory disease; Mycoplasma gallisepticum; chicken