Characterization of Avian Reoviruses Isolated from the Synovia and Breast Blister

SUMMARY Reoviruses Texas, S 1133, UMI 203, and WVU 2937 induced swelling of the foot pad and inflammatory changes in the synovial membranes when inoculated in the foot pad of 2-week-old gnotobiotic chicks. From differences in virus neutralization as measured with geometric mean (R) value, all four viruses are subtypes of a single serotype. The cell-associated and cell-released virus growth curves were similar, with a lag phase of about 15 hours and a log phase of 15 to 21 hours. Viral RNA synthesis reached a peak in 5 hours and was active at 14 hours but not at 18 hours. In 90 minutes at 60 C the titer of each virus had decreased about 4 logs1o.