Premium
Management of drug‐resistant cyathostominosis on a breeding farm in central North Carolina
Author(s) -
LITTLE D.,
FLOWERS J. R.,
HAMMERBERG B. H.,
GARDNER S. Y.
Publication year - 2003
Publication title -
equine veterinary journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.82
H-Index - 87
eISSN - 2042-3306
pISSN - 0425-1644
DOI - 10.2746/042516403776148264
Subject(s) - geography , medicine
Summary Reasons for performing study : Possible anthelmintic resistance on a breeding farm where a rapid rotation anthelmintic programme had been implemented for 9 years was investigated. Cyathostomins resistant to fenbendazole and pyrantel were documented by faecal worm egg count reduction test (FWECRT). Objectives : To 1) manage small strongyle transmission in a herd of horses in which resistance to both pyrantel pamoate and fenbendazole was identified and thereby reduce the risk of clinical disease in the individual animal, 2) monitor the change in resistance patterns over time and 3) monitor the efficacy of ivermectin over the study period. Methods : Targeted ivermectin treatment of horses on the farm was instituted formature horses with faecal worm egg counts (FWEC) >200 eggs/g (epg) and for horses 100 epg. Results : Over a 30 month period, targeted ivermectin treatment achieved acceptable control in mares, as judged by FWEC, and improved control of patent cyathostome infection in consecutive foal crops. Egg reappearance time (ERT) after treatment with ivermectin was <8 weeks in mares and foals more frequently in the second year of the study than in the first year. Numbers of anthelmintic treatments were reduced by 77.6 and 53.3% in the mare and foal group, respectively. Conclusions : Targeted ivermect in treatment may be an economically viable method of managing multiple drug resistant cyathostominosis. Potential relevance : Use of ivermectin should be monitored closely for development of resistance.