Determination of bovine rotavirus G genotypes in Kashmir, India

Rotavirus ribonucleic acid (RNA) was extracted from ten faecal samples of diarrhoeic calves positive for group A rotavirus by enzyme-linked immunosorbent assay (ELISA). A portion of the extracted RNA was run in polyacrylamide gel to determine the presence of rotaviral RNA and the rest subjected to reverse transcriptase-polymerase chain reaction (RT-PCR) to generate the near full length VP7 gene. Only six samples yielded the desired product. The amplified products were subjected to G-typing by PCR using a cocktail of G6, G8 and G10 typing primers. All of the six samples were characterised as G10 and none of the samples revealed mixed infection by twin G types. Four samples, despite possessing sufficient rotavirus particles as revealed by ELISA and polyacrylamide gel electrophoresis, did not yield any amplified product on RT-PCR. This could be due to non-specific inhibitors of the PCR reaction, present in the faecal samples, being carried through the extraction procedures.