Abstract: This study was aimed to investigate the acute toxicity, sub-chronic toxicity and clinical safety of Qinzhu Antai powder, and provide basis for its application for prevention and treatment of domestic cats threatened miscarriage. Acute toxicity test:Qinzhu Antai powder was prepared, sixty 6 weeks old healthy Kunming mice were randomly divided into 5 groups. The doses of groups 1-4 were 6 000, 4 800, 3 840 and 3 072 mg/kg, respectively, and the control group was given the same volume of purified water. After 10 days of feeding, the poisoning symptoms and mortality were observed, and the median lethal dose (LD₅₀) was calculated. Twenty 6 weeks old healthy mice were randomly divided into two groups:The experimental group was given 2.0 g/mL solution 3 times within 18 hours, 0.8 mL each time, and the control group was given the same volume purified water for 7 days, and the maximum tolerance dose (MTD) and tolerance multiple were calculated. Sub-chronic toxicity test:Twenty-four 7 weeks old female SD rats were randomly divided into high, middle and low dose groups and control group, the daily intragastric doses of Qinzhu Antai powder were 4 800, 2 400 and 1 200 mg/kg, respectively, the control group was given the same volume of pure water and fed rats for 30 days, the mental state, poisoning symptoms and mortality of rats in each group were observed and recorded every day. On the 31st day, the rats in each group were weighed and blood samples were collected for hematological examination, the pathological changes of the major organs were observed and pathological sections were made. Clinical safety test:Twenty 2-5 years old healthy female domestic cats were selected and fed adaptively for 10 days. They were randomly divided into 4 groups, the Qinzhu Antai powder dosage was 1, 3 and 5 times of the recommended clinical dose of domestic cats, respectively:1.15 g/kg in low dose group, 3.45 g/kg in middle dose group and 5.75 g/kg in high dose group. The drug was given orally once a day for 7 days. The blank control group was given empty capsule, and the appetite, mental state and defecation of domestic cats in each group were observed every day. Venous blood samples were collected from domestic cats in each group on the 8th day, and blood routine indexes and blood biochemical indexes were detected. The results showed that there was no death in mouse in acute toxicity test, LD₅₀>6 000 mg/kg, the MTD of Qinzhu Antai powder in mouse was 240 g/kg, indicating that the drug was no-toxic. In the sub-chronic toxicity test, there was no significant difference in growth, organ coefficient and blood routine index between each dose and control groups (P>0.05). The content of serum total cholesterol in high and middle dose groups was significantly lower than that in low dose and control groups (P<0.05). There was no significant difference in other biochemical indexes (P>0.05). The results of pathological examination and tissue section observation showed that there was no obvious abnormality in the main tissues and organs of high dose group compared with control group. In the clinical safety test, the mental state, coat glossiness and feces of domestic cats in different dose groups were normal, there were no significant difference in hematological indexes with control group (P>0.05). The results indicated that Qinzhu Antai powder had no obvious toxicity, according to the recommended clinical dose used for domestic cats were safety.

Key words: Qinzhu Antai powder; acute toxicity test; sub-chronic toxicity test; clinical safety test