Höglund, Johan
- Department of Animal Biosciences, Swedish University of Agricultural Sciences
Abstract
Resistance to anthelmintics is an increasing problem in sheep, goat and cattle industries worldwide. For parasite management on farms reliable methods for the detection of resistance are required and it is important that tests give comparable, reproducible and reliable results in different laboratories. The ability of the larval migration inhibition test (LMIT), to detect ivermectin resistance in cattle and sheep nematodes has been evaluated through ring testing in up to six different laboratories in Europe, supported by an EU sixth Framework Project (PARASOL). Third stage larvae of Ostertagia ostertagi, Cooperia oncophora, and Haemonchus contortus with a known resistance status were obtained from faecal cultures of experimentally infected calves and sheep. Following a series of ring tests using identical protocols, reproducible results were obtained within and between participating laboratories. In all tests dose-response curves with R-2 values >0.90 were obtained by all laboratories. Resistance ratios of 8.3 and 8.4 were found when susceptible and IVM-resistant isolates of C. oncophora and H. contortus were compared and differences in the EC50 values were highly significant (p<0.0001). Protocols for the LMIT and the preparation of ivermectin solutions are described in a supplementary file. (C) 2010 Elsevier B.V. All rights reserved.
Keywords
Ivermectin; Resistance; Nematodes; In vitro; Ring test
Published in
Veterinary Parasitology
2010, volume: 174, number: 1-2, pages: 58-64
SLU Authors
Associated SLU-program
AMR: Parasite
UKÄ Subject classification
Animal and Dairy Science
Veterinary Science
Publication identifier
- DOI: https://doi.org/10.1016/j.vetpar.2010.08.020
Permanent link to this page (URI)
https://res.slu.se/id/publ/32277