Two Electropherotypes of Bluetongue Virus Serotype 2 from Naturally Infected Calves Collisson, Ellen W. and Barber, T. Lynwood and Gibbs, E. Paul J. and Greiner, Ellis C.,, 66, 1279-1286 (1985), doi = https://doi.org/10.1099/0022-1317-66-6-1279, publicationName = Microbiology Society, issn = 0022-1317, abstract= SUMMARY The first isolation of bluetongue virus (BTV) serotype 2 in the U.S.A. was in 1982 from a sentinel herd of cattle at Ona, Florida. Electrophoretic analysis of genome RNA revealed that all 16 serotype 2 isolates obtained from this focus of infection had one of two electropherotypes (designated Ona A and Ona B). All genome segments of Ona A and Ona B had detectable differences in electrophoretic mobility, with major differences noted for segments 1, 4, 5, 7, 8, 9 and 10. Electrophoretic comparison revealed that Ona A was indistinguishable from the African serotype 2 prototype isolated 23 years earlier. In 1983, Ona B, in the apparent absence of Ona A, was isolated from two additional cattle herds in Florida. These results suggest that Ona B may be a variant of Ona A that evolved as a result of mutation or reassortment with another BTV strain, and may be better adapted to the selective pressures found in southern Florida. Comparison of the electropherotypes of Ona B with two Florida isolates of serotype 13 and 17 and the prototypes of BTV 10, 11, 13 or 17 produced no evidence for reassortment between Ona A and any of these strains as the possible origin of Ona B., language=, type=