Identification of picobirnavirus, viruses with bisegmented double stranded RNA, in rabbit faeces

Picobirnaviruses are a novel group of viruses recently found in the faeces of several species of vertebrates. Examination by polyacrylamide gel electrophoresis of rabbit faecal samples collected in one animal facility revealed the viruses in 23 (11 per cent) of 211 samples. Further analysis by electron microscopy and caesium chloride isopycnic centrifugation confirmed the presence of picobirnaviruses in the samples. The oral inoculation of three newly weaned rabbits with purified viruses resulted in the excretion of a virus with an electropherotype similar to the inoculum, by two of the three inoculated animals. Maximal viral shedding was detected 13 days after inoculation. No sign of diarrhoea was observed either in the inoculated animals or in the virus excreting animals surveyed. No antibody activity could be detected in the paired serum samples taken from the inoculated animals.