IDENTIFICATION OF HAEMONCHUS SPECIES IN DOMESTIC RUMINANTS BASED ON MORPHOMETRICS OF SPICULES

An easy and rapid tool for the individual identification of Haemonchus species in domestic ruminants might be very useful in the study of na tural populations, especially when two (or three) species are sympatri c. Techniques based on cytology, cuticular-ridge patterns, sublateral hypodermic chords, or molecular biology allow species identification b ut are either expensive or time-consuming. Therefore, a discriminant f unction combining three measures of male spicules was established from experimental infections with H. contortus in both sheep and goats and with H. placei in zebu. The discriminant function was evaluated on in dividual worms and on average values obtained in natural and experimen tal populations throughout the world. It was compared with a previousl y established function. The use of our function permitted better speci es identification for all Haemonchus species of ruminants, including H . longistipes from camels and H. similis from cattle.