Publications

The artificial propagation of salmon starts with the capture of adults as they ascend rivers to spawn. After capture, they are retained in specially constructed holding areas until sexually mature. Though holding periods vary with species, the spring chinook (Oncorhynchus tshawytsca) may be held as long as 4 months before they are spawned. During this interval the fish are often closely...

Aflatoxins (toxic metabolites of the mold Aspergillus flavus) were present in a commercial trout ration causing hepatoma in rainbow trout. Cottonseed meal and solvent extracts of cottonseed meal and of rations containing cottonseed meal and peanut meal were found by chemical assay and confirmed by duckling assay to contain aflatoxins. Diets containing these materials and a purified test...

No abstract available.

Though liver homogenates show apparent microsomal enzyme DDT-dehydrochlorinase activity, in the intact fish the intestinal microflora play a major role in DDT detoxication. Since the presence of this microflora in fish depends on the recent intake of food (12), the rate of detoxication and hence the toxicity of ingested DDT to the rainbow trout will probably depend somewhat on the...

Abstract not available

No abstract available.

The final product of dichlorodiphenyltrichloroethane (DDT) degradation by vertebrates is commonly considered to be dichlorodiphenylacetic acid, DDA (J. E. Peterson and W. H. Robison, Toxicol. Appl. Pharmacol. 6:321, 1964). Recently, certain organisms (A. S. Perry, S. Miller, and A. J. Buckner. J. Agr. Food Chem. 11:457, 1963; J. D. Pinto, M. N. Comien, and M. S. Dunn. J. Biol. Chem. 240...

Hepatoma in commercially reared rainbow trout (Salmo gairdneri) was first seen at this laboratory in April of 1960. The subsequent discovery of it in near epizootic proportions in other hatchery-reared rainbow trout and cutthroat trout (S. clarki) populations throughout the United States precipitated extensive research by numerous agencies. Although the liver neoplasm in trout had been...

The absorption of sulfamethazine by yearling spring chinook salmon (Oncorhynchus tshawytscha) was compared when administered in the Oregon Pellet and a fish-meat diet. The pelleted diet delivered the drug to the fish approximately twice as efficiently as the fish-meat diet. Dosage levels are recommended for both diets, and the efficacy of administering drugs in fish feed is discussed.

Study of a virus disease in the chinook salmon (Oncorhynchus tshawytscha) necessitated the use of a marine environment to study the long range effects of the disease and to complete the life cycle of its etiologic agent. A closed recirculated sea-water system was designed for use under experimental laboratory conditions so that controlled studies of the disease could be made. As others...

No abstract available.

A description was given of a gram-negative, peritrichously flagellated, fermentative bacterium that was isolated on numerous occasions from kidney tissues of rainbow trout (Salmo gairdneri) afflicted with redmouth disease. Although the bacteria apparently were members of the family Enterobacteriaceae, it was impossible to determine their taxonomic position within the family with...