摘要: In 1998, an International Workshop on Equine Cyathostomin Nematodes was held in Athens, Georgia, USA. The purpose of that meeting was to provide a forum dedicated to reviewing new developments in the biology and control of equine cyathostomin parasites. This lead to a special issue of Veterinary Parasitology published in 1999. The problem of anthelmintic resistance was addressed, but only on a conceptual basis, and no broad-based conclusions or recommendations were developed. Since that time, the problem of anthelmintic resistance (AR) has dramatically increased, and is now recognized as a serious problem in the control of equine gastrointestinal nematodes, particularly in the cyathostomins. Benzimidazole resistance is practically ubiquitous in much of the world, resistance to pyrantel is increasing in prevalence, and several studies indicate emerging resistance to avermectin/milbemycin (AM) drugs. Also of particular concern are the worldwide reports of resistance to AM anthelmintics in Parascaris equorum.With the assistance of Dr. Jane Hodgkinson and Dr. Stig Milan Thamsborg, we organized an Equine Parasite Drug Resistance Workshop in Copenhagen, Denmark in 2008, to address these changes. The workshop brought together scientists, veterinary practitioners, representatives from the pharmaceutical industry, and students representing five continents. The meeting featured invited speakers and had blocks of time reserved for discussion. The goals were to develop guidelines for diagnosing anthelmintic resistance, to review the current status of anthelmintic