J. Craven et al., A comparison of in vitro tests and a faecal egg count reduction test in detecting anthelmintic resistance in horse strongyles, VET PARASIT, 85(1), 1999, pp. 49-59
This study reports a comparison between faecal egg count reduction test (FE
CRT), egg hatch assay (EHA) and larval development assay (LDA) for detectin
g anthelmintic resistance in equine strongyles.
Resistance to benzimidazoles was demonstrated in 33 of 42 (79%) farms teste
d by FECRT and in 32 (62%) of the 52 farms tested by EHA. As the reference
strain used was not fully susceptible to benzimidazoles it was not possible
to determine the level of resistance by LDA.
Pyrantel resistance was indicated on three of 15 farms by faecal egg count
reduction. Resistance was also indicated by LDA for one of these farms. In
addition resistance was indicated by LDA on two more farms that were not te
sted by FECRT. Further testing is needed to confirm if these findings are t
ruly indicative of resistance.
Generally, correlations between the tests were poor and it was not possible
to use the outcome of one test to predict the outcome of another. (C) 1999
Elsevier Science B.V. All rights reserved.