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M. C. Quimby

Publications and source records attributed to M. C. Quimby.

At least 19 recordsLinked to original sources
USGS1978

Herpesvirus salmonis: Characterization of a new pathogen of rainbow trout

A new agent, provisionally designated Herpesvirus salmonis , was isolated from post-spawning rainbow trout ( Salmo gairdneri ) 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 3 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 5 PFU/ml and exceeded released virus by a factor of about 10.

Journal of Virology↗
USGS1973

Fish viruses: Buffers and methods for plaquing eight agents under normal atmosphere

A universal procedure was sought for plaque assay of eight fish viruses (bluegill myxovirus, channel catfish virus, eel virus, Egtved virus, infectious hematopoietic necrosis virus, infectious pancreatic necrosis virus, lymphocystis virus, and the agent of spring viremia of carp ( Rhabdovirus carpio ), in dish cultures of various fish cells. Eagle minimal essential medium with sodium bicarbonate-CO 2 buffer (Earle’s salt solution) was compared with minimal essential medium buffered principally with tris (hydroxymethyl)aminomethane or N -2-hydroxyethylpiperazine-N′-2′-ethanesulfonic acid at a pH or in the range of 7.6 to 8.0 depending upon temperature. Five fish cell lines collectively capable of replicating all fish viruses thus far isolated were tested and quantitatively found to grow comparably well in the three media. Two-phase (gel-liquid) media incorporating the various buffer systems allowed plaquing at 15 to 33 C either in partial pressures of CO 2 or in normal atmosphere, but greater efficiency and sensitivity were obtained with the organic buffers, and, overall, the best results were obtained with tris(hydroxymethyl)aminomethane. Epizootiological data, specific fish cell line response, and plaque morphology permit presumptive identification of most of the agents. At proper pH, use of organic buffers obviates the need for CO 2 incubators.

Applied Microbiology↗
USGS1973

Fish viruses: Isolation and identification of infectious hematopoietic necrosis in eastern North America

Infectious hematopoietic necrosis virus (IHNV) was isolated from diseased fingerling rainbow trout ( Salmo gairdneri ) from a hatchery in West Virginia. Clinical signs, histopathologic findings, and origin of eggs provided a basis for diagnosis, and virus was isolated and presumptively identified by plaque characteristics. Serum neutralization tests provided positive identification of the agent as IHNV, and electronmicroscopy showed its rhabdovirus morphology. Experimental infections resulted in signs of IHNV and death; test fish had characteristic histopathologic alterations and appropriate virus titers. This is the first completely documented occurrence of IHNV beyond the Pacific Northwest.

Journal of the Fisheries Research Board of Canada↗
USGS1971

Salmonid viruses: Infectious pancreatic necrosis virus

Epizootics occurred among young trout in France, and the behavior and symptoms suggested infectious pancreatic necrosis (IPN) virus. Specimens preserved in glycerol were sent to the U.S.A. for virological examination. Virus was isolated from four of five lots, but neutralization with antiserum against ATCC VR299 strain IPN virus was incomplete. Electron microscopy, bioassay, histopathology, and serology were used to identify the viruses. The results showed the agents to be new strains of IPN virus with distinctive antigenicity and heretofore unknown lability at 4°C and marked vulnerability to a single freezing and thawing. A method of improving stability in storage was found. Electronmicrographs, tabular and graphic data are presented.

Archiv Fur Die Gesamte Virusforschung↗