title: Efficacy of ivermectin in a topical formulation against induced gastrointestinal and pulmonary nematode infections, and naturally acquired grubs and lice in cattle.
abstract: Efficacy of ivermectin in a topical formulation was evaluated in cattle against adult gastrointestinal and pulmonary nematode infections (experiment 1, n = 24), the 2nd- and 3rd-stage larvae of Hypoderma spp (experiment 2, n = 12), and the biting louse Damalinia bovis (experiment 3, n = 12). Nematode infections were induced and grubs and lice were naturally acquired. Treatments consisted of a single dose of ivermectin in a topical formulation of 200, 500, or 1,000 micrograms/kg of body weight in experiment 1 or 500 micrograms/kg in experiments 2 and 3. At 1,000 micrograms/kg, ivermectin was 100% effective against Ostertagia ostertagi, Trichostrongylus colubriformis, Oesophagostomum radiatum, Nematodirus helvetianus, Haemonchus placei, and Dictyocaulus viviparus and was greater than 99% effective against Cooperia oncophora, C punctata, and T axei. At 500 micrograms/kg, the efficacy was 100% against C oncophora, C punctata, O ostertagi, T axei, Oes radiatum, N helvetianus, Haem placei, and Dict viviparus and greater than 99% against T colubriformis. At 200 micrograms/kg, the efficacy was 100% against Oes radiatum, Haem placei, and Dict viviparus, greater than 99% for O ostertagi, 96% for C oncophora, 86% for C punctata, 90% for T axei, 85% for T colubriformis, and 71% for N helvetianus. At 500 micrograms/kg, ivermectin was highly effective against the grubs Hypoderma bovis and H lineatum and eliminated the louse Damalinia bovis.
mesh_terms: D000287:Administration, Topical; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy*; D004175:Diptera; D004478:Ectoparasitic Infestations / Q000188:drug therapy / Q000662:veterinary*; D005260:Female; D007000:Hypodermyiasis / Q000188:drug therapy / Q000662:veterinary; D007411:Intestinal Diseases, Parasitic / Q000188:drug therapy / Q000662:veterinary; D007559:Ivermectin / Q000008:administration & dosage / Q000627:therapeutic use*; D007814:Larva; D010373:Lice Infestations / Q000188:drug therapy / Q000662:veterinary; D008174:Lung Diseases, Parasitic / Q000188:drug therapy / Q000662:veterinary; D008297:Male; D009349:Nematode Infections / Q000188:drug therapy / Q000662:veterinary*
chemical_list: D007559:Ivermectin