HIGH-MOLECULAR-WEIGHT POLYPEPTIDE BANDS SPECIFIC FOR EQUINE HERPESVIRUS-4

Serum neutralisation (SN) and immunoblotting were used in attempts to distinguish between natural infections with the closely related viruse s equine herpesvirus 1 (EHV-1) and equine herpesvirus 4 (EHV-4), Horse sera (n = 323) collected in 1990 from studs with no experience of EHV -1 abortions as well as 197 sera collected in 1992 from studs with a h istory of EHV-1 abortions were tested by SN. The two groups differed i n the proportion with measurable EHV-1 antibody, the 1992 group being significantly higher. Both groups had high proportions with EHV-4 anti body and no serum had antibody to EHV-1 alone, Pools of positive sera were prepared as probes in immunoblots. High molecular weight (> 200 k Da) polypeptide bands specific for EHV-4 were detected. No bands speci fic for EHV-1 only were found. The specific EHV-4 polypeptides shared some properties with gp2 of EHV-1.