The Efficacy of Milbemycin Oxime in the Treatment of Naturally Acquired Infestations of Sarcoptes Scabiei on Dogs

Milbemycin oxime tablets were evaluated for efficacy against sarcoptic mange mites in naturally infested dogs. Sixty-five dogs were allocated to two groups and were housed individually. Fifty of the dogs were treated orally with milbemycin oxime at the proposed dose. The other fifteen were treated orally with vehicle. Study day 0 was defined as the first day of treatment administration. Dogs were treated on days 0, 7 and 14, and efficacy was assessed by counting viable mites recovered from skin scrapings. To enumerate Sarcoptes scabiei mites, skin scrapings were taken on each of Days-1, 14, 28, 42 and 56. Clinical signs of mange and the extent of sarcoptic lesions were evaluated on each dog when scrapings were made. Evaluation of the efficacy of the treatment was based on the absence of mites supported by the absence of clinical signs associated with canine sarcoptic mange. Treatment with milbemycin oxime at weekly intervals resulted in a rapid reduction of mites and improved clinical signs. Percentage reductions in geometric mean mite counts for milbemycin oxime, compared with vehicle, on days 14, 28, 42, and 56 were 90, 96, 100, and 100%, respectively. The overall cure rates at Day 56, based on zero mite counts and resolution of clinical signs were 100% of dogs. Weekly treatment with maximum dose (2.0g/kg) rate of milbemycin oxime for continually three weeks, was effective against naturally acquired infestations of sarcoptes scabiei in dogs, reducing mites counts by 100%.