Cyathostome nematodes have become the central focus of concerns related to internal parasites of horses due to their pathological and persistent effects on the growing and mature horse (Murphy and Love, 1997). Current anthelmintic treatments have, however, led to resistance and alternative control measures are required. Glucosinolate hydrolysis derivatives have a wide range of biological activities, and have previously been shown to inhibit root nematodes (Brown and Morra, 1997). The aim of the study was to examine whether cyathostome nematode eggs could be inhibited by glucosinolate hydrolysis products.

An in vitro egg hatch assay was set up using eggs extracted from the faeces of naturally infected horses (Kassai, 1999). The egg suspension (containing approximately 100 eggs) were incubated with nine different concentrations (range: 20-10,000 ppm) of the glucosinolate hydrolysis products (allyl isothiocyanate (C), allyl nitrile (N) and phenethyl isothiocyanate (P). A control was set up in which water replaced the hydrolysis product. The number of eggs and larvae were counted using an inverted microscope. Statistical differences between treatments were assessed using General Linear Model, ANOVA.