Morpho-Molecular Characterization of Cattle Haemonchus Nematodes From Southeast of Iran

Haemonchosis is one of the most important nematode infections in cattle population. Knowledge of genetic diversity and morphological analysis can provide a foundation for understanding the drug resistance, epidemiological features, and control strategies in a geographical area.

The aims of this study were to evaluate the morphological parameters and molecular targets (ITS1-ITS2 and Beta-tubulin) of cattle Haemonchus nematodes from southeast of Iran and to find species diversity and benzimidazole resistance.

From May 2016 to April 2017, 300 abomasa of cattle slaughtered at slaughterhouses of Zabol, Zahedan, and Iranshahr were inspected. Ninety-eight adults male Haemonchus nematodes were morphologically analyzed. For molecular analysis, the amplification of ITS1, 5.8S and ITS2 regions, and Beta-tubulin fragment was done.

All specimens were morphologically identified as H. contortus. The ITS2 sequencing and the phylo-genetic tree revealed 99% similarity between H.contortus from this study and those from other parts of the world. There was no mutation in the positions and all nematodes were benzimidazole susceptible.

Our results showed that although H. placei is the most common Haemonchus species in the cattle around the world, H. contortus is mostly prevalent in southeast region of Iran. Moreover, it seems that the induction of benzimidazole resistance is less important in many parts of the world.