Speed of actin of some anthelmintics against Dictyocaulus viviparus infection in cattle.

In a study of the comparative speed of action of anthelmintics against Dictyocaulus viviparus infection in cattle levamisole reduced the lungworm burdens by 87 per cent within three hours of administration whereas fenbendazole and febantel required 36 hours to achieve 80 and 87 per cent reduction, respectively. The more rapid action of levamisole may be advantageous in the treatment of bovine parasitic bronchitis since it allows virtually immediate elimination of the majority of the lungworms and limits undesirable sequelae dependent on the continued presence of the parasite.