Journal of Veterinary Parasitology

The polymerase chain reaction (PCR) was used for amplification of ß-tubulin gene, followed by its restriction fragment length polymorphism (RFLP) analysis to identify four gastro-intestinal nematodes viz., Haemonchus contortus, Trichostrongylus colubriformis, Teladorsagia circumcincta and Oesophagostomum columbianum, infecting small ruminants. The PCR was performed using adult and single larval DNA of the four nematodes. The PCR of ß-tubulin gene of all four nematodes generated 840 bp fragment and in nested PCR the product size was 770 bp. Restriction enzyme analysis with Rsa I generated different restriction patterns in three species. Alu I was used to differentiate O. columbianum and T. colubriformis. PCR followed by RFLP was successfully used in diagnosis of the infection of the host with these four strongyle nematodes at their larval stage.