Eighteen farms located throughout the North and South Islands of New Zealand were used to test the efficacy and safety of a new anthelmintic. Monepantel is the first compound from the recently discovered amino-acetonitrile derivative (AAD) class of anthelmintics to be developed for use in sheep.
On each farm, sheep naturally infected with the target nematodes were randomly assigned to groups, which were then treated with either monepantel, at a minimum dose rate of 2.5 mg/kg, or one of five other anthelmintics.
Fecal samples were collected from all sheep pre-treatment, at the time of treatment, and approximately 7, 14, and 21 days after treatment. Facal egg counts (FEC) were measured in all samples. All sheep were inspected at least daily to check for any adverse effects of treatment.
On all 18 farms, on days 7, 14 and 21, the efficacy of the monepantel solution was greater than 95 percent. At days 7 and 14 post-treatment, efficacies greater than 99 percent were recorded in 15 flocks. At day 21 post-treatment, efficacies over 98 percent were recorded in 13 flocks.
Monepantel was as effective, or more effective, than the registered anthelmintics with which it was compared. Moreover, it was effective against strains of nematodes resistant to one or more of the currently available broad-spectrum anthelmintics.
The monepantel solution used in this study was well tolerated by the sheep, and no adverse events could be attributed to its use.
Source: New Zealand Veterinary Journal Volume 57 Issue 1