ABSTRACT
The purpose of this study was to document the prevalence and to analyze morphological characteristics from hydatid cysts to test their suitability for strain identification. In the present study, 4,130 animals, including 278 cattle, 298 buffaloes, 760 sheep, 2,439 goat and 355 pigs were examined for the presence of hydatid cysts on post-mortem inspection at different slaughter houses/shops in northern India. Morphological characteristics from hydatid cysts were analyzed to test their suitability for strain identification. For statistical analysis, five variables were considered: number of hooks per rostellum, blade length of large and small hooks, and total length of large and small hooks. Principal component analysis was applied for analysis of morphological parameters. Out of a total of 4,130 animals examined, 66 were positive for hydatid cysts (prevalence 1.598 %). The prevalence of hydatid cysts was highest in cattle (5.39 %) followed by buffaloes (4.36 %), pigs (3.09 %), sheep (2.23 %) and goat (.41 %). The results indicate significant prevalence of hydatidosis in all the food producing animals and further that morphological analysis can also be used as a valid criterion for differentiation of different strains of E. granulosus particularly in developing countries where molecular studies could not be performed due to lack of infrastructure or financial constraints.
ABSTRACT
Echinococcosis is an important medical, veterinary and economic concern in India. Ten cysts were randomly selected from each intermediate host species (cattle, buffalo, sheep, goat and pigs). Either the germinal layer (sterile cysts) or protoscoleces (fertile cysts) were collected for molecular characterization. A 434 base pair fragment of the mitochondrial cytochrome oxidase-1 gene was amplified using PCR from each isolate. Ten representative samples (2 from each intermediate host species) were sequenced in both the directions from which readable sequences were obtained from nine for phylogenetic analysis (NCBI, Blast). Phylogenetic analysis of cytochrome oxidase I gene revealed that seven (77.7%) isolates, from cattle (2), pigs (2), buffaloes (1) and goat (2) were clustered with the Indian Buffalo (G3) strain of Echinococcus granulosus, while two (22.2%) isolates from sheep were clustered with the sheep strain (G1) of E. granulosus. Phylogenetic analysis of the cytochrome oxidase-1 gene revealed that the buffalo strain (G3) and common sheep strain (G1) are cycling among livestock in north India and that these strains are highly adapted to cattle, buffalo, sheep, goats and pigs.
