Genotyping of calves rotavirus in China by reverse transcription polymerase chain reaction.

To investigate the epidemical characteristics and genotype distributions of bovine rotavirus (BRV) in China, 195 fecal samples were collected from calves with diarrhea in China. Fecal samples were detected for rotavirus A antigen using ELISA. The positive samples were screened for VP7 and VP4 by RT-PCR. G serotyping and P genotyping were conducted on 53 VP7 and VP4 positive samples using RT-PCR. The results showed that 82 samples were found positive for BRV. 752bp, 660bp and 285bp bands were amplified for G-typing. 478bp, 375bp and 361bp bands were amplified for P-typing. The G6 and G10 serotypes were 29 (54.7%) and 8 (15.1%) in positive samples for VP7. P[5] and P[11] genotypes were 28 (52.8%) and 10 (18.9%) in the positive samples for VP4. The main combinations of BRV G serotype and P genotype were G6P[5] (28.3%), G6P[5]P[11] (5.7%), G10P[5] (5.7%) and G10G6P[5] (5.7%), respectively. Other combinations (including untypable) of G serotype and P genotype were 54.6%. The dominant G serotype and P genotype were G6 and P[5] respectively. The predominant combination of G and P serotypes was G6P[5]. This has significance for establishing the preventive measures against diarrhea caused by group A rotaviruses in cattle.