The efficacy of mixtures of albendazole sulphoxide and levamisole against sheep nematodes resistant to benzimidazole and levamisole.
Faecal egg count reduction tests and an anthelmintic efficiency assay were used to assess the efficacy of combinations of albendazole sulphoxide and levamisole against populations of Ostertagia and Trichostrongylus sp. which contained different proportions of worms resistant to both benzimidazole and levamisole anthelmintics. Compared to the effects of either drug alone, significantly greater efficacy was obtained using combinations which included dose rates similar to those recommended for the separate components. At these dose rates, the mixtures reduced mean faecal egg counts by 95% or more, and caused a reduction of 68% in adult Ostertagia sp. and more than 95% for 4th stage Ostertagia and T colubriformis. The increased efficacy of the mixtures could be accounted for by actions of the drugs acting independently.
Anderson
N
N
CSIRO Division of Animal Health, Animal Health Research Laboratory, Parkville, Victoria.
Martin
P J
PJ
Jarrett
R G
RG
D015766:Albendazole / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use*; D001562:Benzimidazoles / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D005243:Feces / Q000469:parasitology; D007978:Levamisole / Q000494:pharmacology / Q000627:therapeutic use*; D010028:Ostertagia / Q000187:drug effects; D010029:Ostertagiasis / Q000188:drug therapy / Q000662:veterinary; D010270:Parasite Egg Count / Q000662:veterinary; D012756:Sheep; D012757:Sheep Diseases / Q000188:drug therapy*; D014252:Trichostrongyloidiasis / Q000188:drug therapy / Q000662:veterinary*; D014253:Trichostrongylosis / Q000188:drug therapy / Q000662:veterinary; D014254:Trichostrongylus / Q000187:drug effects
D000871:Anthelmintics; D001562:Benzimidazoles; D007978:Levamisole; D015766:Albendazole; C027186:albendazole sulfoxide