Genomic characterisation of the large segment of a rabbit picobirnavirus* and comparison with the atypical picobirnavirus of Cryptosporidium parvum

The 2362 base pair sequence of the larger of the two double stranded RNA ge nome segments of a rabbit strain of picobirnavirus (PBV) has a major open r eading frame (ORF) of 591 amino acids and two smaller ORFs of 55 and 155 am ino acids. A clone of the segment did not hybridise with other viral bisegm ented ds RNAs from faecal samples. There is no relationship in sequence or organisation between this PBV sequence and the bisegmented dsRNAs found ass ociated with Cryptosporidium parvum. This suggests that there are at least two distinct classes of bisegmented dsRNA viruses or viral-like agents in f aeces.