COMPARISON OF EPIZOOTIC HEMATOPOIETIC NECROSIS AND BOHLE IRIDOVIRUSES, RECENTLY ISOLATED AUSTRALIAN IRIDOVIRUSES

Epizootic haematopoietic necrosis virus (EHNV) and Bohle virus (BIV) a re piscine and amphibian iridoviruses respectively which have been iso lated in Australia from redfin perch Perca fluviatilis L., cultured ra inbow trout Oncorhynchus mykiss (Walbaum) and the ornate burrowing fro g Limnodynastes ornatus (Gray). To determine whether the viruses were similar they were examined at the ultrastructural, protein, antigenic and genomic levels. EHNV was found to differ from BIV in cytopathic ef fect on host cells, size, site of virus release, molecular weights of proteins and restriction endonuclease digest profiles of the respectiv e DNA's. On the other hand both iridoviruses were also found to infect a similar range of tissue culture cells, exhibit a similar sequence o f ultrastuctural events and possess proteins of similar antigenic reac tivity. DNA from EHNV and BIV cross hybridized to a high level. When t he BIV polypeptides were compared to the published data for purified f rog virus 3 (FV3) and with the appropriate restriction enzyme profiles , a similarity was noted between the 2 viruses. This implies that EHNV , which shares many structural and biochemical characteristics with BI V, is itself related to the Ranavirus genus of iridoviruses.