Study of β-tubulin gene polymorphisms in Haemonchus contortus isolated from sheep populations in Khouzestan, southwestern Iran

In this report, β-tubulin gene polymorphism was investigated in Haemonchus contortus  populations isolated from sheep flocks in different regions of Khouzestan province, southwestern Iran. The samples were chosen on the basis of regional variation in benzimidazole treatment background of sheep flocks. Our objective was to study the relationship between treatment background andβ -tubulin gene polymorphism of H. contortus isolated from the selected regions. H. contortus isolated from Shooshtar revealed reduction in β-tubulin gene polymorphism restriction fragment length polymorphism (RFLP) in respect to other isolates indicating that benzimidazole-resistant isolates of H. contortus  developed in some sheep flock of Shooshtar region.