Identification and molecular characterization of some trematodes of domestic ruminants parasitic in snail intermediate hosts

Intramolluscan larval stages of Fasciola gigantica, Explanatum explanatum, Paramphistomum epiclitum, Fischoederius elongatus and Schistosoma spindale infecting various aquatic snails were identified and species confirmed for using ribosomal DNA viz. internal transcribed spacer-2 (ITS-2), 28S rDNA, 12S mitochondrial DNA and COX1 markers. Genomic DNA was isolated from randomly selected Lymnaea auricularia, L. luteola, Gyraulus convexiusculus and Indoplanorbis exustus, collected from three districts of U.P (Bareilly, Meerut and Jhansi), Ranchi (Jharkhand) and Jabalpur (M.P). These snails were screened for larval trematode infections by polymerase chain reaction (PCR) amplification ofthe genomic DNA for the above markers. Restriction fragment length polymorphism (RFLP) profiles of the PCR products with different restriction enzymes were generated and PCR amplicons sequenced for species identification. The above markers are suitable in the identification of the prepatent stages of the trematode parasites and their genetic variants (if any) prevalent in the snail intermediate hosts.