Publications
Publications from USGS science centers throughout the Southeast Region.
Filter Total Items: 9965
Role of intestinal microflora in the degradation of DDT by rainbow trout (Salmo gairdneri)
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 available food s
Authors
Gary Wedemeyer
Some effects of mirex on two warm-water fishes
The effects of mirex on two species of warm-water fishes were studied in three experiments in which the fish were exposed either by feeding a mirex-treated diet, or by treating the holding ponds with a mirex formulation. Bluegills were used in the feeding experiment, where three different levels of mirex were incorporated into the diet and fed to fish held in plastic pools, and in the first pond-e
Authors
Charles C. Van Valin, Austin K. Andrews, Lafayette L. Eller
The relative toxicities of several pesticides to naiads of three species of stoneflies
Static bioassays were conducted to determine the relative acute toxicities of some insecticides, herbicides, fungicides, a defoliant, and a molluscicide to the naiads of three species of stonef!y, Pteronarcys califomica, Pteronarcella badia, and Claassenia sabulosa. Toxic effects were measured by determination of median lethal concn (Lcoo) for 24-, 48-, and 96-hr exposures, at 15.5C. Endrin and di
Authors
Herman O. Sanders, Oliver B. Cope
Electrophoretic separation of fish brain esterases
Fish brains were homogenized in an all-glass Potter-Elvehjem-type tissue grinder in 40% sucrose solution. The homogenate concentration was 10 brains/ml for both the bluegill and channel catfish. The brei was centrifuged at 34,700 g for 30 min at 5 C, and 30 J.lliters of the supernatant were used per column for electrophoresis.
Authors
Charles O. Knowles, Suresh K. Arurkar, James W. Hogan
Degradation of organophosphates by fish liver phosphatases
Liver homogenates of bluegill, Lepomis macrochirus Rafinesque, and channel catfish, Ictalurus punctatus (Walbaum), were shown by a manometric technique to contain soluble enzymes capable of degrading diisopropyl phosphorofluoridate (DFP) and 2,2-dichlorovinyl dimethyl phosphate (dichlorvos). Hydrolysis of the compounds was greatest in the presence of the manganic ion. Tentative identification of c
Authors
James W. Hogan, Charles O. Knowles
Some enzymatic properties of brain Acetylcholinesterase from bluegill and channel catfish
Using a manometric technique an acetylcholinesterase (EC 3.1.1.7, acetylcholine acetyl-hydrolase) was demonstrated in brain tissue from the bluegill, Lepomis macrochirus Rafinesque, and the channel catfish, Ictalurus punctatus (Walbaum). The activities were 19 and 37 μmoles acetylcholine hydrolyzed/milligram protein per hour for the bluegill and channel catfish enzymes, respectively. The optimum s
Authors
James W. Hogan, Charles O. Knowles
The oxidation of drugs by fishes
1. Fish liver microsomal systems have been found to catalyze the hydroxylation of aniline and acetanilide, the N-demethylation of aminopyrine and the O-dealkylation of phenacetin.2. These systems are similar to the corresponding mammalian enzymes and they may be considered to be mixed function oxidase since they require NADPH and oxygen. An absolute requirement for oxygen, however, was difficult t
Authors
Donald R. Buhler, Mary E. Rasmusson
Piezometric surface of principal artesian aquifer in coastal area of Georgia, December 1966
No abstract available.
Authors
R. L. Wait, D. O. Gregg
Salt-water encroachment in the South Edisto River Estuary, South Carolina
No abstract available.
Authors
T. Ray Cummings
Flood profile study, Squaw Creek, Linn County, Iowa
This report is the result of a cooperative agreement between the city of Cedar Rapids and the U.S. Geological Survey that provides for the collection of hydrologic data by the Geologic Survey on small streams in and near the city. The city furnished the large-scale topographic map showing a stream reference line marked off in 100-foot stations and a part of the data on valley cross sections used i
Authors
Climate and streamflow of Puerto Rico
The presently available data on streamflow, runoff rainfall, and temperature of Puerto Rico are evaluated, although the period of record is very short, with a view to contributing to the knowledge of hydrology of tropical islands. The average annual streamflow in Puerto Rico is 45 percent of the annual rainfall, or 15 percent more than in the eastern piedmont of the U.S. where it is 30 percent. Cl
Authors
E.V. Giusti, M. A. Lopez