Isolation and G-typing of Rotaviruses from diarrheal Calves in Tehran and Alborz provinces, Iran

Rotaviruses group A are the major cause of diarrhea in calves under one month and every year causes enormous economic losses. Serological and molecular techniques can be used for rapid detection of rotaviruses but virus isolation requires specific methods of cell culture and suitable cell lines. In this study, 41 samples were collected from diarrheal calves up to the age of one month, from industrial and semi-industrial farms in Tehran and Alborz provinces. The samples were positive by RT-PCR on VP6 gene. After preparation and inoculation onto MA104 cells in roller tube culture and constant cell culture system, the cytopathic effect (CPE) was observed. Eligible cultured with CPE, were confirmed by two-step RT-PCR using VP6 gene primers. Semi-nested PCR using VP7 gene primers was also performed for G-genotyping in which 11 and 2 samples were detected as G6 and G10, respectively. This is the first report on isolation and identification of rotaviruses, one of the causative agents of viral diarrhea in Iran. The results of this research suggest that, these two types, can be used as the dominant strains for manufacturing a suitable vaccine against the rotaviruses in Iran.