| Background:Haemonchosis has a negative effect on the farming industry throughout the world, especially in the tropic and sub-tropic countries. The present study was carried out to differentiate Haemonchus species from its main hosts in Iran, including sheep, goat and camel. Methods:The identification took place based on the morphometrics of the spic-ules and molecular characters. Two hundred seventy adult male nematodes were collected from the abomasums of different ruminants (90 samples from each ani-mal) at the slaughterhouses from different localities in Iran. Samples were morpho-logically identified according to the spicules’ morphometric measurements. In the section on molecular study, 10 samples of each Haemonchus isolates were genetically examined. A simple PCR-restriction fragment length polymorphism (PCR-RFLP) assay of the second internal transcribed spacer of ribosomal DNA (ITS2-rDNA) were described to confirm the PCR results. Results:PCR-RFLP profile obtained from the restriction enzyme HPa1 in H. con-tortus and H. longistipes indicated 1 (278 bp) and 2 (113 and 135 bp) different frag-ments, respectively. The morphological parameters clearly distinguish H. contortus from H. longistipes. Moreover, regarding the ITS2-rDNA, sequences of 295 bp and 314 bp were obtained from H. contortus and H. longistipes, respectively. Conclusion:High similarity of cloned PvMSP-142 kDa gene in comparison to reference sequence and other sequences could be beneficial as a remarkable mo-lecular marker for serological diagnostic. |