Two trials were conducted to evaluate the therapeutic and prophylactic activity of
milbemycin oxime (
Interceptor, Novartis Animal Health) against the eye-worm Thelazia callipaeda (Spirurida, Thelaziidae)
infection. In Trial 1, the therapeutic efficacy of
milbemycin oxime was evaluated in 55 naturally infected dogs treated with min. 0.5mg/kg
milbemycin oxime. The dogs were clinically examined for the presence of eyeworms before and again 7 days
after treatment. Dogs still positive were given a second treatment and re-checked again a week later. Forty-eight of the 55 dogs tested negative 1 week
after treatment (87.3% reduction of
infection rate). Following the second treatment 6 of these 7 dogs tested negative 1 week later resulting, after two treatments, in a reduction of
infection rate of 98.2%. In Trial 2, the prophylactic efficacy of
milbemycin oxime was evaluated in 60 uninfected dogs. Thirty dogs were treated with
milbemycin oxime monthly from June to November with the recommended dose rate for the prevention of
heartworm disease (> or =0.5mg/kg), 30 dogs served as untreated controls. At the end of the trail 1 dog in the treated group and 10 dogs in the control group became infected during the trial. The incidence of
infection differed significantly between treated and control dogs (p=0.0056). The efficacy of the prophylactic use of a monthly treatment with
milbemycin oxime showed 90% efficacy in reducing T. callipaeda
infection rate.