Combo Treatment Remains Effective
Combination treatments are now recommended for clinically parasitized sheep/goats, but what happens if you give them for several years? Argentinian researchers evaluated the efficacy of a combination treatment, given continuously over a 4 year period.
Forty lambs were divided into four groups (n=10): control (no treatment), moxidectin (MOX), levamisole LEV), and moxidectin + levamisole (MOX + LEV). Drugs were injected subcutaneously. MOX and LEV were administered separately. The clinical efficacy of the continuous use of MOX + LEV combination was assessed with a controlled efficacy test (CET), performed at the beginning and end of the study, and with the fecal egg count reduction (FECR) test, performed over the four-year study period.
In the first year, the CET showed efficacies of 84.7%, 100%, and 97.4% for Haemonchus, Teladorsagia, and Trichostrongylus, respectively, for the combination treatment. After repetitive use of the combination treatment for four years, the efficacy remained high (100%) and only decreased to 58% for T. colubriformis.
The evaluation of FECR over the study period showed fluctuations in efficacy in the performance of the combined treatment. The initial FECR was 99% (MOX), 85% (LEV), and 100% (MOX+LEV). The combined treatment resulted in a significantly higher anthelmintic effect: 87% versus 42% and 69% for when moxidectin and levamisole were given alone.
Source: Veterinary Parasitiology. February 2021. View Abstract