Anthelmintic resistance

Drug (anthelmintic) resistance is a major issue in the small ruminant industry and an emerging problem in other segments of animal agriculture. Drug resistance exists when an anthelmintic treatment fails to reduce fecal egg counts by more than 95 percent. It is inevitable. Severe resistance exists when treatment fails to reduce worm egg counts by more than 60 percent. Currently, there is resistance to all of the anthelmintics used to treat small ruminants (in the US). The level of resistance varies by geographic region and farm.

Articles

Dewormers and dewormer resistance; part 4 in a six part series on worm control in goats. Steve Hart, Langston University, and American Consortium for Small Ruminant Parasite Control. Orginally published in The Goat Rancher Magazine [June 2008].

Dewormer resistance on farms in the Mid-Atlantic Area. D.J. O'Brien, Delaware State University. [May 2010].

Do you know which dewormer(s) are effective on your farm? E. Nelson Escobar, University of Maryland Eastern Shore. [Timely Topic, July 2013].

The DrenchRite Assay; by Sue Howell and Bob Storey, Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia [Timely Topic, August 2012].

Slowing drug resistance. Dewormer resistance is inevitable, but the speed by which it develops is not. by Susan Schoenian, University of Maryland Extension [August 2013].

Conference proceedings

; Dr. Ray Kaplan, Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia; 10th Anniversary Conference of the American Consortium for Small Ruminant Parasite Control [May 2013].

Journal articles

Anthelmintic resistance on sheep and goat farms in the southeastern United States; S.B. Howell, J.M. Burke, J.E. Miller, T.H. Terrill, E. Valencia, M.J. Williams, L.H. Williamson, A.M. Zajac, and R.M. Kaplan; Scientific Reports: Journal of American Veterinary Medical Association [December 2008].

DrenchRite plate used to determine anthelmintic resistance