Isolation and identification of a variant of bluetongue virus serotype 11 from a ram in a bluetongue outbreak in western Texas.

A field strain of bluetongue virus was isolated from a blood sample of a ram during an outbreak of bluetongue in November 1985 in western Texas. In this bluetongue outbreak at least 25 of the 2,000 sheep were infected. Isolation was made by intravenous inoculation of 11-day-old embryonated chicken eggs. The serotype was identified as serotype 11 by serum neutralization tests. The genomic pattern on sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) of the new isolate is similar to that of bluetongue virus prototype 11. Comparisons were also made with proteins labeled in vivo with [3H]leucine and separated by SDS-PAGE. We conclude that this virus belongs to serotype 11, with slight differences in both genome and protein electrophoretic patterns.