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C. E. Dunbar

Publications and source records attributed to C. E. Dunbar.

18 recordsLinked to original sources

Two new species of Plistophoroa (Microsporidea) from North American fish with a synopsis of Microsporidea of freshwater and euryhaline fishes

Two new species of Microsporidea, Plistophora salmonae from steelhead and rainbow trout (Salmo gairdntri) and Plistophora crpedianar from gizzard shad ( Dorosoma cepedianum) are described. Schizonts to spores of P. cepedianae were found at one time within the same cyst, while only sporonts and spores of P. salmonae were found within the cyst. An illustrated synopsis of the known Microsporidea of freshwater and euryhaline fishes is given.

Journal of Protozoology

Visceral granuloma in brook trout (Salvelinus fontinalis)

Brook trout were fed a synthetic diet with suspect diet components added or a meat-meal diet with individual components removed to determine their effect on the incidence of visceral granuloma. Removal or addition of cottonseed meal had the greatest effect on incidence. Gossypol was not the causative agent. The disease is characterized, histologically, by the presence of Langhans-type giant cells and concretions like Schaumann bodies giving an apparent similarity to sarcoidosis in humans. Gross symptoms of the disease are papillary growths of connective tissue on the serosal surface of the stomach, and calcification of the posterior kidney. In severe cases, lesions may be present throughout the visceral mass. Visceral granuloma is similar to nephrocalcinosis in rainbow trout and may be the same disease modified by difference in species response.

Journal of Nutrition

Characteristics and identification of oxidative Pseudomonads isolated from diseased fish

Several characteristics of 20 strains of oxidative pseudomonads, all but one of which were isolated from freshwater fish, were determined. All strains oxidized glucose and gluconate, produced NH 3 from 1 % peptone, grew at 6, 12, 20 and 30° and produced cytochrome oxidase. Lipase was produced by 17 of the strains, while 15 produced gelatinase, and 16 produced fluorescent pigment. These and other characteristics used to identify fish-spoilage pseudomonads are also useful for identification of fish-pathogenic pseudomonads. Species determinations from the present data were not attempted. However, from previously published data on speciation of Pseudomonas , most of the 20 strains appeared to be closely related to or identical with P. fluorescens .

Journal of General Microbiology

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