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Geology topics

Donald F. Amend

Publications and source records attributed to Donald F. Amend.

22 records · Page 2Linked to original sources
USGS1970

Experimental control of Columnaris sisease with a new Nitrofuran drug, P-7138

P-7138 is a new, broad-spectrum, vinylogous, nitrofuran chemotherapeutic that was developed specifically for treating fish diseases. Although it can be added to the diet of fish, therapeutic tissue levels can be obtained in eels (Anguilla japonica) and goldfish (Carassius auratur) by absorption of the drug directly from the water. Moreover, the drug is eliminated from the tissues within hours and shows a low level of toxicity (Shimizu and Takase 1967). The purpose of the present study was to deterime 910 the efficacy of P-7138 in controlling an experimentally induced Chrondrococcus columnaris infection, 920 the absorption and elimination rates, and 930 the degree of acute and chronic toxicity to coho salmon (Oncorhynchus kitutch).

Progressive Fish-Culturist↗
USGS1969

Some factors influencing susceptibility of rainbow trout to the acute toxicity of an ethyl mercury phosphate formulation (Timsan)

This study determined the influence of water temperature (55–68° F), dissolved oxygen (4–12 ppm), water hardness as CaCO 3 (20–256 ppm), and chloride ions (to 2 mM) on the susceptibility of rainbow trout ( Salmo gairdneri ) to the acute toxicity of ethyl mercury phosphate (EMP). The fish were exposed for one hour to 0.125 ppm EMP, the active ingredient of Timsan, a commercial EMP formulation. The death rate because of the exposure to EMP increased with an increase in water temperature, a decrease in dissolved oxygen, and an increase in chloride ions; calcium appeared to have no effect. The effect of water temperature and dissolved oxygen was ascribed to changes in the respiration rate of the fish, and a chemical explanation is presented for the effect of chloride ions.

Transactions of the American Fisheries Society↗
USGS1969

A hematopoietic virus disease of rainbow trout and sockeye salmon

A previously undescribed virus disease epizootic of hatchery rainbow trout ( Salmo gairdneri ) in British Columbia, Canada is presented. In the same locality, a similar virus disease was experienced among hatchery sockeye salmon ( Oncorhynchus nerka ). Typical symptoms included flashing, fecal casts, hemorrhagic areas at the base of fins, and petechial hemorrhages on the visceral fat and membranes in the abdominal cavity. Histopathologic changes were typified by extensive degeneration and necrosis in the hematopoietic tissues of the kidney and spleen. A virus was isolated from both species of fish on tissue culture and the viruses showed cross-infectivity. Based upon the pathological changes in the hematopoietic tissue and the demonstration of a vital infection, a tentative descriptive name was designated Infectious Hematopoietic Necrosis. The isolated viruses were distinctly different from the infectious pancreatic necrosis or viral hemorrhagic septicemia viruses of trout, but did show similarities to the Oregon sockeye and Sacramento River chinook viruses. Positive identification awaits further tests. The significance of these observations is the reporting of a new viral disease of rainbow trout and the extension of the geographic range of sockeye salmon viruses.

Transactions of the American Fisheries Society↗