The Larval Migration Inhibition Assay as a bases of determining resistance in sheep nematodes with emphasis on practicality and reproducibility

Abstract

Resistance against anthelmintics is a growing problem in many parts of the world, with Haemonchus contortus being one of the most resistant and most pathogenic nematodes of sheep. Different tests are used to investigate resistance in both worms and larvae, the LMIA being one of the new tests standardized first by Demeler et al (2010). Because of the way this standardized test was performed in high tech laboratories and with known strains of larvae, the question was risen whether this test could be used in the field and thus if it is practical and if the results could be reproduced elsewhere. To investigate this, unknown strains of larvae were used as well as other materials preserving the method as good as possible. It was found that results were difficult to reproduce. On practicality, it was found that if this test should be introduced in the field it should be further standardized and personnel should be thoroughly trained in the use of the test. Thus, it was difficult to reproduce the same results as the test used by Demeler et al (2010), but the test shows promise as to being used in the field.