APPLICATION OF MOLECULAR BIOLOGICAL TECHNIQUES FOR DETECTION OF EPIZOOTIC HEMORRHAGIC-DISEASE VIRUS (EHDV-318) RECOVERED FROM A SENTINEL CALF IN CENTRAL SUDAN

Epizootic hemorrhagic disease virus (EHDV), isolate 318 (EHDV-318), an untyped virus recovered from a sentinel calf herd at the Khartoum Uni versity farm in central Sudan, was characterized using molecular biolo gical techniques. With dot blot hybridization technique, a cDNA probe derived from genome segment 6 of EHDV-2 (Alberta strain) hybridized wi th RNA from EHDV-318. Application of serogroup-specific EHDV polymeras e chain reaction (PCR) to EHDV-318 RNA resulted in specific amplificat ion of a 387 bp PCR product. Amplification product was visualized on e thidium bromide-stained agarose gel. Specificity of the PCR products w as confirmed by chemiluminescent hybridization with a non-radiolabelle d internal probe. No amplification product or hybridization signal was detected when the serotype-specific EHDV-1 or EHDV-2 PCR-based assays were applied to RNA from EHDV-318. The scientific data presented in t his study indicated that cDNA probes and serogroup-specific PCR-based assay can be used to classify the virus as a member of EHDV serogroup, and as serotypically distinct from EHDV-1 and EHDV-2.