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Geology topics

K. Wolf

Publications and source records attributed to K. Wolf.

At least 109 records · Page 6Linked to original sources
USGS1965

Infectious pancreatic necrosis: its detection and identification

Ultimate control of infectious pancreatic necrosis (IPN) in hatcheries depends largely upon learning where the virus occurs. To detect the presence of virus either susceptible fish or susceptible fish cell cultures may be used as test systems. In modern virology, it is generally agreed that cell cultures are more convenient, are usually a much more sensitive test system, and allow more rapid determinations.

Progressive Fish-Culturist↗
USGS1963

Egg-associated transmission of IPN virus of trouts

Infectious pancreatic necrosis virus (IPN) of salmonid fishes has been isolated and identified in suspect but normal-appearing stocks of adult brook trout ( Salvelinus fontinalis ), and thus a pattern for the epizootiology of the virus has been demonstrated. Virus titers as high as 10 6.5 ID 50 were found in egg fluids from 7 of 12 fish tested. In contrast, egg homogenates contained much less virus; their maximum titer was 10 1.8 ID 50 . The presence of virus within the eggs, however, was not established. Viral neutralizing ability of serum from the same fish showed an inverse relationship to the presence of virus in “ovarian fluid.” The highest serum titers occurred in those fish from which little or no virus had been isolated.

Virology↗
USGS1962

Experimental propagation of lymphocystis disease of fishes

The agent of lymphocystis disease has been propagated under laboratory conditions for more than 2 years. Although several hatchery-propagated centrarchids are susceptible, the bluegill ( Lepomis macrochirus ) is the host of choice because it is most easily maintained. At 12.5° the disease was transmitted by implantation and by injection, but there was no evidence of fish-to-fish spread, nor seasonal change in host susceptibility. The infective agent was clearly demonstrated to be filterable (Millipore HA). It retained infectivity in storage at −20° for almost two years, and its viability after desiccation was confirmed. These facts support its postulated viral nature. The virus was glycerol- and ether-sensitive and did not induce formation of giant lymphocystis cells in monolayer cultures of bluegill ovary cells.

Virology↗
USGS1960

Preparation of monolayer cell cultures from tissues of some lower vertebrates

Cold trypsin dispersion at p H 7.2 was used to obtain cultivable cells and cell groups from tissues of six species of fresh-water bony fishes, a frog, and a turtle. The cells readily attached to glass and were capable of at least limited, and in some cases extended, division in media consisting of commercially available components.

Science↗
USGS1959

Test of 34 therapeutic agents for control of kidney disease in trout

Sixteen strains of fish kidney disease bacterium were tested in vitro to determine their reaction to 34 therapeutic agents. On the basis of the results obtained ten of the drugs were employed in experimental therapy of kidney disease in eastern brook trout (Salvelinus fontinalis). Erythromycin at the rate of 100 milligrams per kilogram of fish per day (4.5 grams per 100 pounds of fish) for 21 days gave the best results. Other drugs gave only temporary benefit if any.

Transactions of the American Fisheries Society↗