Safety of moxidectin in avermectin-sensitive collies.
OBJECTIVE
To evaluate the safety of moxidectin administration at doses of 30, 60, and 90 microg/kg of body weight (10, 20, and 30 times the manufacturer's recommended dose) in avermectin-sensitive Collies.


METHODS
24 Collies.


METHODS
Collies with mild to severe reactions to ivermectin challenge (120 mg/kg; 20 times the recommended dose for heartworm prevention) were used. Six replicates of 4 dogs each were formed on the basis of body weight and severity of reaction to ivermectin test dose. Within replicates, each dog was randomly allocated to treatment with oral administration of 30, 60, or 90 microg of moxidectin/kg or was given a comparable volume of placebo tablet formulation. Dogs were observed hourly for the first 8 hours and twice daily thereafter for 1 month for signs of toxicosis.


RESULTS
Signs of toxicosis were not observed in any control group dog throughout the treatment observation period. Likewise, signs of toxicosis were not observed in any dog receiving moxidectin at 30, 60, or 90 microg/kg.


CONCLUSIONS
The moxidectin formulation used in the study reported here appears to have a wider margin of safety than ivermectin or milbemycin in avermectin-sensitive Collies.
Paul
A J
AJ
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana 61802, USA.
Tranquilli
W J
WJ
Hutchens
D E
DE
D000284:Administration, Oral; D000818:Animals; D000871:Anthelmintics / Q000008:administration & dosage / Q000009:adverse effects / Q000592:standards*; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000592:standards; D001835:Body Weight; D016001:Confidence Intervals; D004285:Dogs / Q000378:metabolism* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D005260:Female; D007559:Ivermectin / Q000009:adverse effects*; D018942:Macrolides; D008297:Male; D011897:Random Allocation
D000871:Anthelmintics; D000900:Anti-Bacterial Agents; D018942:Macrolides; D007559:Ivermectin; C027837:moxidectin