The σC Gene Characterization of Seven Turkey Arthritis Reovirus Field Isolates in Pennsylvania during 2011-2014

Seven turkey arthritis reovirus (TARV) field isolates made in our laboratory during 2011-2014 were characterized by sequencing of reovirus σC genes. Of the seven TARV field isolates, six were isolated from 3-to-17-week-old turkeys with tenosynovitis in six Pennsylvania farms and one was isolated from an Indiana turkey case submitted to our lab in 2014. This report describes the amplification and sequencing of the σC genes for genetic characterization studies on the seven TARV field isolates. Phylogenetic analysis of the sequence data of the seven TARV isolates together with recent published five TARVs detected in Minnesota (MN) and 25 avian reovirus (ARV) strains retrieved from GenBank revealed that all the seven PA TARV field isolates and five MN TARVs fit into genotyping cluster two when compared with a total of five different genotyping clusters (cluster 1-5) generated by the TARV and ARV reference strains. Comparison of amino acidsequences of the seven TARV isolates in cluster two with ARV vaccine strains (S1133, 1733, and 2048) in cluster one revealed that there were less than 60% similarity in nucleotide sequence and less than 56% in amino acid sequence between the two clusters. However the seven PA TARV isolates shared greater than 99% similarity with each other. Our research findings have indicated that the seven PA TARV field isolates and the five MN TARVs are grouped in the same genotype two, a separate genotype or virus species within the Orthoreovirus genus.