R. W. Darlington W.G. Taylor M. C. Quimby T. Nagabayashi K. Wolf 1978 <p><span>A new agent, provisionally designated&nbsp;</span><i>Herpesvirus salmonis</i><span>, was isolated from post-spawning rainbow trout (</span><i>Salmo gairdneri</i><span>) and studied primarily in the RTG-2 rainbow trout cell line. Infection of RTG-2 cells resulted in the formation of syncytia and Cowdry type A intranuclear inclusions. Replication occurred regularly at 5 and 10°C, but was inconsistent at 15°C, largely inhibited at 0°C, and completely inhibited at 20°C or higher. The virus was acid, heat, ether, and chloroform labile, but stable to freezing and thawing. It did not hemagglutinate. Viral DNA had a buoyant density of 1.709 g/cm</span>³<span>&nbsp;and a guanine-cytosine value of 50%. Hexagonal nucleocapsids had a diameter of 90 nm and were first seen in nuclei at 36 h. Enveloped forms measured about 150 nm and occurred both cytoplasmically and extracellularly. At 10°C, a one-step growth culture required about 96 h; cell-associated virus peaked at about 10</span>⁵<span>&nbsp;PFU/ml and exceeded released virus by a factor of about 10.</span></p> application/pdf 10.1128/jvi.27.3.659-666.1978 en American Society for Microbiology Herpesvirus salmonis: Characterization of a new pathogen of rainbow trout article