Characterization of a group D rotavirus

A rotavirus isolated from the intestinal contents of commercial ring-neck pheasant chicks was identified as a group D rotavirus based on its RNA electropherotype and its serological relatedness to known turkey group A and D rotaviruses using immune electron microscopy and agar-gel immunodiffusion assays. Further characterization revealed a buoyant density in caesium chloride of 1.347 g/cm³ for double-shelled particles and 1.365 g/cm³ for single-shelled particles. The average size of the pheasant-origin group D rotavirus was 80 and 70 nm for double- and single-shelled particles, respectively. In contrast, the average size for a turkey group A rotavirus isolate was 73 and 60 nm, respectively. There was no evidence of viral replication by the pheasant-origin group D rotavirus (either cytopathic effect or increase in numbers of viral particles) after 6 passages in MA104 cells. The haemagglutinating activity of the pheasant origin group D rotavirus was compared with that of a turkey origin group A rotavirus. Differences and similarities were noted depending upon the species of erythrocytes employed and the temperature of incubation.