Morphological and molecular characterization of Haemonchus contortus isolated from the small ruminants of south Gujarat, India.

The successful design of strategic control measures against the blood-sucking gastrointestinal nematode, in small ruminants can be facilitated by revealing its general features from morphology to the molecular level. In the south Gujarat region of India, a total of 2408 were collected from 84 slaughtered sheep's abomasum, consisting of 347 males and 2061 females (1:6 ratio) (p<0.05). Furthermore, 726 were collected from 61 goats, comprising 145 males and 581 females (1:4 ratio) (p<0.05). The male worms were approximately 12±0.06 mm long, while female worms were about 20±0.09 mm long. The vulvar morphotypes of the female worms were found to be 17.7% linguiform, 76.6 % knobbed/button (p<0.05), and 5.7 % smooth type, demonstrating common features of . The nucleotide sequences of the Internal Transcribed Spacer 1 (ITS-1) of 165 bp or ITS-2 plus of 256 bp were aligned, and it was found that the genotypes of male and female specimens of either sheep or goat origin were identical, with a 100 % match. The present isolates shared >95 % and >94 % homology with published sequences of ITS-1 and ITS-2 plus of , respectively, with more nucleotide transitions than transversions in the aligned sequences. The reconstructed phylogram of either ITS-1 or ITS-2 plus revealed two major clades, one for and another for other nematodes, with showing its proximity with the clade of . The study established the role of morphological and molecular features in identifying and differentiating parasite at the local level.