Morphological characteristics of Echinococcus granulosus derived from buffalo in Iran.

Cystic echinococcosis is a significant parasitic disease in Iran, where a variety of animals act as intermediate hosts. In this study, 25 isolates of Echinococcus granulosus obtained from water buffalo from various parts of Iran were characterized on the basis of the morphology of the metacestode and the adult worm. The characteristics of protoscoleces from the different studied areas were nearly similar. They showed 2 rows of alternating large and small hooks and their shapes were smooth in outline. In contrast to the protoscoleces, the adult rostellar hooks showed a rough outline. The results showed that the total length, the blade lengths of the large and small hooks and the number of hooks are almost similar to those isolated from sheep but significantly different from those isolated from camels. The growth rates of adult E. granulosus (total worm length, segmentation and maturation) of buffalo origin, at 35 and 41 days post-infection of dogs, were nearly comparable to the common sheep strain. The form of the strobila and the morphology of the reproductive system were also similar to those of sheep origin. This suggests that the common sheep strain (G1) of E. granulosus may also use buffaloes as its intermediate host.

Comparative genotyping of Echinococcus granulosus infecting buffalo in Iran using cox1 gene.

Twenty-five isolates of Echinococcus granulosus protoscoleces from hydatid cysts were collected from 25 buffaloes in five different provinces of Iran. DNA was extracted from protoscoleces and used for phylogenetical analysis. For this aim, the DNA was amplified using specific primers derived from cox1 gene and, subsequently, the corresponding polymerase chain reaction products were sequenced. The sequence analysis showed five genotypes within the samples. Twenty-three isolates were identified as G1 and under grouped as separate genotypes: G1α, G1ß, G1γ and G1δ, and two isolates were identified as G3 strain in Iran. G3 strain has not been already reported in buffaloes in Iran. The nucleotide and amino acid sequences of cox1 gene from corresponding isolates were documented in GenBank under accession numbers: HM130574, HM130575, HM130576, HM130577, HM130578, HM130579, HM130580, HM130581, HM130582, HM130583, HM130584, HM130585, HM130586, HM130587, HM130588, HM130589, HM130590, HM130591, HM130592, HM130593, HM130594, HM130595, HM130596, HM130597 and HM 130598.