SPECIES IDENTIFICATION OF TRICHOSTRONGYLE NEMATODES BY PCR-LINKED RFLP

Restriction fragment length polymorphisms (RFLP) of the second interna l transcribed spacer (ITS-2) of ribosomal DNA were examined for 6 spec ies of ruminant nematodes; Trichostrongylus colubriformis, T. axei, T. vitrinus, Haemonchus contortus, Teladorsagia circumcincta and Cooperi a oncophora. The ITS-2 of each species was amplified by PCR and restri cted with the endonucleases DraI, HinfI, RsaI and VspI. Using this app roach, the 6 species could be distinguished. No intraspecific variatio n in RFLP's has been detected so far in the ITS-2 of these species, su ggesting that this technique has considerable potential for the identi fication of eggs of different nematode species in faecal samples.