USGS Science⌕ Search

SEARCH · USGS Science

Results for “Lipids”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

455 records · Page 26Linked to original sources
USGS1989

Persistent infections of fish cell lines by paramyxovirus isolates from Chinook salmon ( Oncorhynchus tschawytscha )

We have reported the isolation of a paramyxovirus from stocks of adult chinook salmon ( Oncorhynchus tshawytscha ) returning to coastal rivers of Oregon, USA (Winton et al 1985). The isolates were obtained from kidney and spleen tissues using the chinook salmon embryo cell line, CHSE-214. Initial cytopathic effect (CPE) was slow to develop, requiring 28 days incubation at 18°C. The virus replicated in CHSE-214, chum heart (CHH-1), kokanee ovary (K0-6), coho salmon embryo (CSE-119), and fathead minnow (FHM) cell lines where it produced a lytic type of CPE. The virus was stable at pH 3-11 and iodo-deoxyuridine did not inhibit wiral replication. Infectivity was lost after treatment with chloroform indicating the presence of essential lipids. The density of virions in CsCl was 1.2 g/ml. The virus hemagglutinated cells of 11 of 14 species of birds, mammals, and fish tested. Electron microscopy of infected cells revealed enveloped particles 125-250 nm in dia. containing coiled nucleocapsids and examination of freon-treated virions showed the nucleocapsid was a helix approximately 18 nm in dia. and > 1000 nm in length (Winton et al 1985). In addition to causing hemagglutination, members of the Paramyxoviridae are known for the ability to establish persistent infections of cell lines (Choppin and Compans 1975). The purpose of this study was to determine if the paramyxovirus isolates from salmon were able to establish persistent infections in fish cell lines and to study the nature of the infection.

Book chapter↗
USGS2006

Toxicokinetics and effects of PCBs in Arctic fish: a review of studies on Arctic charr

In a series of environmentally realistic laboratory experiments, toxicokinetics and effects of polychlorinated biphenyls (PCBs) were studied in the Arctic charr (Salvelinus alpinus). Winter fasting and emaciation, which are common among Arctic charr living in high latitudes, resulted in a redistribution of the lipophilic PCBs from lipid-storing tissue such as the muscle, to vital organs that must be considered sensitive toward PCB (liver and brain). This redistribution was accompanied by a significant potentiation of the hepatic cytochrome P-450 (CYP) 1A biomarker response, from low activities in October (within those measured in uncontaminated charr) to a high, probably maximum, induction in May. Performance studies demonstrated a clear effect of environmentally realistic PCB levels on endocrine mechanisms, immune function, and seawater preadaptation (smoltification) in charr that had been feed deprived for several months after contamination with Aroclor 1254, whereas a high PCB dose exerted only minor, if any, effects in charr that had been fed after contamination. These results demonstrate that emaciation results in decreased dose-response relationships in fish, and indicate that arctic animals undergoing seasonal cycles of "fattening" and emaciation may be extra sensitive toward persistent, lipophilic organochlorines. Pilot studies on Arctic charr from Bjørnøya Island revealed marked CYP1A biomarker responses and an upregulation of genes involved in cellular homeostatic mechanisms in charr from Lake Ellasjøen (high PCB levels).

Journal of Toxicology and Environmental Health, Pa↗
USGS2005

Non-lethal estimation of body composition of Yukon River salmon

Because of the importance of Chinook salmon to commercial and subsistence fisheries on the Yukon River, further study of the factors that may affect the success of this species and our ability to manage the fisheries is warranted. Critical to these studies is the determination of the amount of lipids (fat) stored and available to the fish as its primary energy source for migration and spawning. Recent developments of Bioelectrical Impedance Analysis (BIA) promise a simple, non-lethal means of estimating proximate composition (e.g. fat, protein, water content) for field applications with fish. The goal of the project was to develop BIA models for Chinook salmon from the Yukon River watershed that would permit the non-lethal estimation of body proximate composition for use in field studies. Our results clearly demonstrated that BIA can be used to estimate proximate composition and energy density of salmon. While some minor refinements were suggested, the methodology can be used in a wide variety of field applications. For instance, application of the BIA models to predict energy levels of fish during their migration will allow evaluation of management programs, while also yielding data that can be used to evaluate energy use along the migratory path. Correlations of energy level with ongoing tagging, radio-tracking, and genetic studies also have the potential to allow managers and scientists to understand the relationship between fat content and distance to spawning location. These models have the potential for application to this species in other river systems. They also provide tools for a variety of other scientific investigation such as: 1) differences in energy stores in spawning and recruitment success; 2) effects of global warming on migratory salmonid stocks; and 3) differences in annual flow and temperature regiments upon migratory energy costs and resulting recruitment success.

Alaska, Yukon↗
USGS2006

Basic alumina flash chromatographic separation of bulk ortho-PCBs from on-ortho-PCBs, PBDEs, PCDFs, PCDDs, PCDTs, OCPs, and PCTs

Comprising nearly 100 congeners in environmental samples, PCBs are often still prevalent in concentrations exceeding 1 μg/g. To effectively measure PCBs, they are isolated as a group from other persistent organic pollutants using silica gel, Florisil, or alumina column chromatography for analysis by GC/MS or dual capillary column GC/ECD. When organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) are also targeted, PCBs are often split into two chromatographic eluates. In contrast to the major ortho-substituted PCB congeners, much lower concentrations occur for congeners of polychlorinated- dibenzo- p -dioxins (PCDDs), dibenzofurans (PCDFs), dibenzothiophenes (PCDTs), naphthalenes (PCNs), and dioxin-like non- ortho -PCBs 1 . Such co-planar compounds are usually separated from the bulk PCBs using a carbon LC 2 or reusable porous graphitic carbon HPLC column 3 eluted forward ( o -PCBs, mono- o -PCBs, then non- o -PCBs) before reversal with toluene (PCDFs and PCDDs) and additional separation with basic alumina to remove PCNs, polychlorinated diphenyl ethers (PCDEs), and residual lipid for PCDF/PCDD GC/HRMS analysis. Recently, smaller particle-size normal phase adsorbents including active basic alumina have become available along with custom-made glass columns for use in low pressure flash chromatography. With low gas pressure (< 1-2 bar) and particles 32-63 μm, flash chromatography is a rapid, inexpensive technique with enhanced resolution compared to gravity column chromatography 4 . However, few environmental researchers use the technique, but basic alumina is in the automated PowerPrep LC system for PCDFs, PCDDs, PCBs and PBDEs 5 . A flash LC column is quickly dry-packed, gives improved flow performance, and has sufficient resistance to gravity flow without a shutoff valve. Contamination from lab air, dust, and sample carryover is minimized by using high purity nitrogen, much smaller eluate volumes and blown down in tubes with high purity nitrogen. The disposable adsorbent is used only once with an inert, nonleachable, reusable and cleanable glass column with glass joints and disposable glass fiber. We evaluated basic alumina flash chromatography initially for PCBs, because Loos et al. 6 had separated 13 selected o -PCB congeners from three non- o -PCBs (77, 126, and 169) and then from PCDFs and PCDDs with eluants of 150- 200 mL each from a large 25-g basic alumina (Super 1 active) column. Because the elution properties of other PCB congeners were unknown in addition to some PBDEs, PCDTs, and other compounds, we chose to evaluate basic alumina flash chromatography comprehensively. We optimized the separation of all bulk o-PCBs from all non- o- PCBs, tested other pollutants (PBDEs, PCDTs, PCDFs and PCDDs) under similar elution conditions, and finally applied the chromatographic technique to samples known or suspected to contain complex mixtures of these.

Organohalogen Compounds↗
USGS2018

Direct substitution of fishmeal with bioprocessed soybean meal in brown trout diets

This 121-day experiment evaluated the rearing performance of juvenile brown trout ( Salmo trutta ; initial weight 56.1±1.6 g, length 167.2±1.4 mm, mean ±SE) fed one of four isonitrogenous and isocaloric diets (46% protein, 16% lipid). Fishmeal, the primary protein source for the reference diet, was compared to diets where bioprocessed soybean meal directly replaced approximately 60, 80, or 100% of the dietary fishmeal. At the end of the experiment there were no significant differences in gain, percent gain, food fed, feed conversion ratio, nor specific growth rate among any of the dietary treatments. Gains for the 0, 60, 80, and 100% treatments were 304.6 ± 40.3 g, 215.4±82.6 g, 199.0±39.4 g, and 218.1±37.0 g, respectively. There were also no significant differences observed in intestinal morphology, relative fin lengths, viscerosomatic index, hepatosomatic index, or splenosomatic index among the dietary treatments. Based on these results, bioprocessed soybean meal may be able to replace 100% of the dietary fishmeal in juvenile brown trout diets without any deleterious effects.

Journal of Fisheries and Aquaculture Development↗