Haemaphysalis concinna(Acari: Ixodida): Persistent efficacy of doramectin in rabbits under laboratory conditions

Abstract

In the present study, the persistent efficacy of doramectin (DOR) in rabbits infested by Haemaphysalis concinna was observed. DOR (200 µg/kg) was administered once to infested rabbits by subcutaneous injection. A total of 15 rabbits were allocated to three groups, which were observed for efficacy. On days 1–7, 8–14, 15–21 and 22–28 post‐inoculation, the percent reduction of tick larvae in DOR treated rabbits was 100.0, 100.0, 86.7 and 61.7%, respectively; the percent reduction of nymphs was 100.0, 90.0, 75.0 and 65.0%, respectively; and the percent reduction of adults was 85.0, 65.0, 55.0 and 55.0%, respectively. In comparison, in untreated rabbits at the same time points (control group), the percent reduction of larvae was 5.0, 3.3, 5.0 and 5.0%, respectively, and there was no reduction of nymphs and adults in the untreated rabbits.