Doramectin, a new avermectin highly efficacious against gastrointestinal nematodes and lungworms of cattle and pigs: two studies carried out under field conditions in Germany.
Two field studies were carried out to confirm the efficacy of doramectin in cattle and pigs in Europe. A total of 40 cattle harbouring naturally acquired infections of gastrointestinal nematodes, including Ostertagia spp., Oesophagostomum spp., Cooperia spp., Haemonchus spp., Nematodirus spp. and Trichuris spp., were allocated to a treated or a control group (20 animals/group), and 100 harbouring naturally acquired infections of gastrointestinal nematodes and lungworms, including Oesophagostomum spp., Metastrongylus spp., Ascaris suum and Trichuris suis, were allocated to either a treated (60 pigs) or a control (40 pigs) group. Animals in the treated groups received an injection of doramectin at 200 micrograms/kg (1 ml/50 kg) for cattle or 300 micrograms/kg (1 ml/33 kg) for swine. Animals in the control groups received saline at 1 ml/50 kg for cattle or 1 ml/33 kg for swine. The cattle were injected by the subcutaneous route in the lateral mid-line of the neck and the pigs were injected intramuscularly in the neck. Faecal egg counts were determined for all animals on days--7, 0, 7, 14 and 21 of the studies, where day 0 was the day of treatment. The mean daily weight gain of doramectin-treated animals was significantly higher than that of the control animals over the 21 days of the studies (P < 0.0007 for cattle and P = 0.0001 for swine). At 21 days after treatment, the mean faecal egg counts of the doramectin-treated animals were significantly lower than those of the control animals and were reduced by 100% as compared with pretreatment levels. No adverse reaction to treatment was observed in any animal during either study.(ABSTRACT TRUNCATED AT 250 WORDS)
Mehlhorn
H
H
Department of Zoology and Parasitology, Ruhr University Bochum, Germany.
Jones
H L
HL
Weatherley
A J
AJ
Schumacher
B
B
D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use*; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy*; D005243:Feces / Q000469:parasitology; D005858:Germany / Q000453:epidemiology; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000627:therapeutic use; D007814:Larva; D008099:Liver / Q000469:parasitology; D009349:Nematode Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000473:pathology / Q000662:veterinary*; D010270:Parasite Egg Count; D013552:Swine; D013553:Swine Diseases / Q000188:drug therapy*; D015430:Weight Gain
D000871:Anthelmintics; D007559:Ivermectin; C084101:doramectin