Molecular detection of genogroup I and II picobirnaviruses in pigs in China.

In this study, a total of 187 stool specimens were collected from a pig farm in Hunan province of China, from November 2011 to June 2012. 39 (20.9 %) stool specimens were positive for picobirnaviruses using reverse transcription-polymerase chain reaction. Among 39 stool specimens, 84.6 % (33/39) were identified to be genogroup I (prototype 1-CHN-97), 38.5 % (15/39) belonged to genogroup II (prototype 4-GA-91), and 23.1 % (9/39) of which showed the evidence of genogroup I picobirnavirus were also positive for genogroup II picobirnaviruses. Picobirnaviruses exist in pigs which were divided into five groups according to the age and physiological status. Nineteen representative strains of genogroup I picobirnaviruses and eleven strains of genogroup II picobirnaviruses detected in this study were selected to analyze their phylogenetic relationships with other picobirnaviruses reference strains. The phylogenetic tree analysis suggested the prevalence of multiple picobirnaviruses in pigs in China.