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At least 55 records · Page 3Linked to original sources
USGS1996

Effects of dietary lipid on the hematology of channel catfish, Ictalurus punctatus

Juvenile channel catfish were fed diets containing either soybean oil, menhaden oil, beef tallow, or a combination of these three lipid sources. After 90 days, total erythrocyte, leucocyte, and thrombocyte counts, hematocrit, mean corpuscular volume, plasma recalcification time, erythrocyte osmotic fragility, total serum iron, and iron-binding capacity were measured. Total erythrocyte counts, leucocyte counts, and mean corpuscular volume were not significantly different ( P < 0.05) among dietary groups. However, fish fed the menhaden oil diet had significantly lower ( P < 0.05) hematocrits, higher thrombocyte counts, and higher serum iron concentrations. They also had the highest concentration of n − 3 fatty acids in the pronephros tissue and their erythrocytes were the least susceptible to osmotic lysis. Catfish fed the beef tallow diet had the lowest level of n − 3 fatty acids in pronephros tissue and their erythrocytes were the most susceptible to osmotic lysis. Results suggest that dietary lipids affect several hematological factors of cultured channel catfish.

Aquaculture↗
USGS2005

Effects of body size, condition, and lipid content on the survival of juvenile lake herring during rapid cooling events

Juvenile lake herring Coregonus artedi were exposed to rapid cooling events during two laboratory experiments to determine the effects of body size, physiological condition, and lipid content on survival. The first experiment was conducted at the onset of winter, exposing small (50 to 85 mm) and large (85 to 129 mm) fish to a decline in water temperature from 12 to 2°C at a rate of 1°C/hr. During this experiment, both large and small individuals exposed to a rapid cooling event experienced no mortality or abnormal behaviors. Separate fish were then maintained under thermal and photoperiod regimes that mimicked those in Lake Superior from October through May. Fish in each size class were maintained at two feeding treatments: Artemia ad libitum and no food. At the completion of the winter period, these lake herring were subjected to the same rapid cooling event conducted in the first experiment. During the experiment, lake herring exhibited no mortality or abnormal behaviors despite treatment-dependent differences in condition and lipid content. Our results indicate that mortality due to rapid cooling events does not appear to contribute to the recruitment variability observed for juvenile lake herring in Lake Superior.

Journal of Great Lakes Research↗
USGS2003

Relation of fatty acid composition in lead-exposed mallards to fat mobilization, lipid peroxidation and alkaline phosphatase activity

The increase of n-6 polyunsaturated fatty acids (PUFA) in animal tissues has been proposed as a mechanism of lead (Pb) poisoning through lipid peroxidation or altered eicosanoids metabolism. We have studied fatty acid (FA) composition in liver and brain of mallards ( Anas platyrhynchos ) feeding for 3 weeks on diets containing combinations of low or high levels of vitamin E (20 or 200 UI/kg) and Pb (0 or 2 g/kg). Saturated FA, n-6 PUFA and total concentrations of FA were higher in livers of Pb-exposed mallards, but not in their brains. The percentage of n-6 PUFA in liver and brain was slightly higher in Pb-exposed mallards. The increase of n-6 PUFA in liver was associated with decreased triglycerides and increased cholesterol in plasma, thus could be in part attributed to feed refusal and fat mobilization. The hepatic ratios between adrenic acid (22:4 n-6) and arachidonic acid (20:4 n-6) or between adrenic acid and linoleic acid (18:2 n-6) were higher in Pb exposed birds, supporting the existing hypothesis of increased fatty acid elongation by Pb. Among the possible consequences of increased n-6 PUFA concentration in tissues, we found increased lipid peroxidation in liver without important histopathological changes, and decreased plasma alkaline phosphatase activity that may reflect altered bone metabolism in birds.

Comparative Biochemistry and Physiology, Part C: T↗
USGS1999

Determination of uptake kinetics (sampling rates) by lipid-containing semipermeable membrane devices (SPMDs) for polycyclic aromatic hydrocarbons (PAHs) in water

The use of lipid-containing semipermeable membrane devices (SPMDs) is becoming commonplace, but very little sampling rate data are available for the estimation of ambient contaminant concentrations from analyte levels in exposed SPMDs. We determined the aqueous sampling rates (R(s)s; expressed as effective volumes of water extracted daily) of the standard (commercially available design) 1-g triolein SPMD for 15 of the priority pollutant (PP) polycyclic aromatic hydrocarbons (PAHs) at multiple temperatures and concentrations. Under the experimental conditions of this study, recovery- corrected R(s) values for PP PAHs ranged from ???1.0 to 8.0 L/d. These values would be expected to be influenced by significant changes (relative to this study) in water temperature, degree of biofouling, and current velocity- turbulence. Included in this paper is a discussion of the effects of temperature and octanol-water partition coefficient (K(ow)); the impacts of biofouling and hydrodynamics are reported separately. Overall, SPMDs responded proportionally to aqueous PAH concentrations; i.e., SPMD R(s) values and SPMD-water concentration factors were independent of aqueous concentrations. Temperature effects (10, 18, and 26 ??C) on Rs values appeared to be complex but were relatively small.The use of lipid-containing semipermeable membrane devices (SPMDs) is becoming commonplace, but very little sampling rate data are available for the estimation of ambient contaminant concentrations from analyte levels in exposed SPMDs. We determined the aqueous sampling rates (Rss; expressed as effective volumes of water extracted daily) of the standard (commercially available design) 1-g triolein SPMD for 15 of the priority pollutant (PP) polycyclic aromatic hydrocarbons (PAHs) at multiple temperatures and concentrations. Under the experimental conditions of this study, recovery-corrected Rs values for PP PAHs ranged from ???1.0 to 8.0 L/d. These values would be expected to be influenced by significant changes (relative to this study) in water temperature, degree of biofouling, and current velocity-turbulence. Included in this paper is a discussion of the effects of temperature and octanol-water partition coefficient (KOW); the impacts of biofouling and hydrodynamics are reported separately. Overall, SPMDs responded proportionally to aqueous PAH concentrations; i.e., SPMD RS values and SPMD-water concentration factors were independent of aqueous concentrations. Temperature effects (10, 18, and 26??C) on RS values appeared to be complex but were relatively small.

Environmental Science & Technology↗
USGS2026

Variation in diet and lipid content of age-0 sturgeon (Scaphirhynchus sp.) in the lower Missouri River basin

Shovelnose sturgeon ( Scaphirhynchus platorynchus ) and related endangered pallid sturgeon ( S. albus ) are species of interest in the highly modified Missouri River. Scaphirhynchus sturgeon require long distances of riverine habitat for the development of drifting free embryos along with suitable foraging habitat during the subsequent transition to exogenous feeding. Working with specimens collected by the US Army Corps of Engineers and Nebraska Game and Parks Commission, we examined diet composition of age-0 (<12 cm) sturgeon at four reaches in the lower Missouri River to examine the potential role of prey acquisition at this vulnerable life stage. In general, Ephemeroptera were more represented at reaches further upstream in the lower Missouri River, whereas Diptera larvae were the dominant prey item in reaches downstream. Body condition, as measured by total lipid content and length‒weight regressions, exhibited spatial differences in 2016 but not in 2017. Even with differences in prey frequencies and numbers consumed, percent consumption regardless of prey type remained consistent among reaches within years, but was overall higher in 2016 when river discharge was greater. Although temporal and spatial differences were observed in condition, comparisons using previous data from 2014 and 2015 suggest that these condition results were not driven by the longitudinal variability in prey composition as the reaches below Kansas city yielded relatively high and low lipid values despite the limited consumption of ephemeropteran prey relative to upstream reaches. Although it is unknown if any of the observed differences affected survival, our results, coupled with previous work, suggest that age-0 sturgeon can opportunistically forage in the lower Missouri River.

Missouri River↗
USGS2020

How lipid content and temperature affect American shad (Alosa sapidissima) attempt rate and sprint swimming: Implications for overcoming migration barriers

How seasonal effects such as temperature increases and reduced lipid content affect the ability of anadromous fishes to traverse high-velocity barriers and sprint swimming is poorly understood. We evaluated American shad ( Alosa sapidissima ) swimming performance in a flume against high flow velocities (2.5–3.7 m·s −1 ) during the upstream migration period (April–May; temperatures 11.1–21.4 °C) to determine how their willingness to enter a velocity barrier (attempt rate) and their swimming endurance changed during migration. American shad did not make attempts at low temperatures, and attempt rate gradually increased throughout the migration as temperatures warmed. American shad displayed two distinct, nonsustained swimming modes (prolonged and sprint swimming), and endurance was different between sexes. At warmer temperatures, females swam at prolonged speeds more often and longer females displayed a lower endurance. Males primarily swam at sprint speeds and were affected by swimming speed, fork length, and lipid content. Our results indicate that American shad motivation and swimming endurance change over the course of the migration as conditions change, potentially limiting their ability to pass barriers.

Canadian Journal of Fisheries and Aquatic Sciences↗
USGS2005

Plasma lipid metabolites and refueling performance of Semi palmated Sandpipers at migratory stopovers

Assessing stopover habitat quality and refueling performance of individual birds is crucial to the conservation and management of migratory shorebirds. Plasma lipid metabolites indicate the trajectory of mass change in individuals and may be a more accurate measure of refueling performance at a particular site than static measures such as nutrient reserves. We measured lipid metabolites of Semipalmated Sandpipers at 4 coastal stopover sites during northward migration: Merritt Island, FL; Georgetown, SC; Pea Island, NC; and Delaware Bay, NJ. We described spatial and temporal variation in metabolic profiles among the 4 stopovers and evaluated the effects of body mass, age, and date on metabolite concentrations. Triglyceride concentration, an indicator of fat deposition, declined during the migration, whereas B-OH-Butyrate, a measure of fasting, increased. Triglyceride concentration correlated with phospholipids and inversely related to B-OH-butyrate, but was not related to body mass or age. Triglyceride levels and estimated percent fat were greater at Delaware Bay than at any stopovers to the south. Plasma metabolite profiles accurately reflected stopover refueling performance and provide an important new technique for assessing stopover habitat quality for migratory shorebirds.

Book chapter↗
USGS1990

Body mass and lipid content of shorebirds overwintering on the south Texas coast

Three species of shorebirds were collected at bimonthly intervals in 1979-1980, from the time of their arrival in early autumn to mid-February, on the south Texas coast. Female Long-billed Dowitchers (Limnodromus scolopaceus) and Western Sandpipers (Calidris mauri) were heavier (P < 0.05) than males, but the reverse was true for American Avocets (Recurvirostra americana). Lipid content, relative to whole body mass, did not differ (P > 0.05) between sexes in any of the three species. During the wintering period, fat stores in Long-billed Dowitchers and Western Sandpipers declined 70% and 44%, respectively, but not in American Avocets. Lipid content was highly correlated (P < 0.001) with body mass in all three species, providing further evidence that fat accumulation is responsible for the major variation in total mass of some shorebird species.

Journal of Field Ornithology↗
USGS1995

Evaluation of lipid-containing semipermeable membrane devices for monitoring organochlorine contaminants in the Upper Mississippi river

Organochlorine contaminants sequestered in lipid-containing semipermeable membrane devices (SPMDs) were compared to those found in tangential-flow ultrafilter permeates as part of a pilot study at 10 sites in the Upper Mississippi River system. Caged and feral fish from three primary sites were also analyzed for comparison. Concentrated organochlorine (OC) compounds were readily extracted from the SPMDs by dialysis into hexane, and samples were analyzed by gas chromatography-negative chemical ionization-mass spectrometry. Fish and water samples were processed by conventional methods. Reasonable agreement was found between analyte SPMD-derived water concentrations and measured values of ultrafilter permeates; however, concentrations of the same analytes in caged fish did not appear to be proportional to water concentrations derived from SPMDs and ultrafilter permeates. The greatest number of OC compounds was detected in SPMDs; fewer were detected in caged fish and feral fish.

Illinois, Iowa, Minnesota, Missouri, Wisconsin↗
USGS1977

The stereoisomeric composition of phytanyl chains in lipids of Dead Sea sediments

Lipid extracts from five recent Dead Sea sediments were analyzed for isoprenoid compounds and the following were isolated: free and phospholipid-bound di- O -phytanylglycerol, free phytanol and free and esterifled phytanic acid. The phytanyl groups of the diether and the free phytanol were oxidized to the corresponding phytanic acid; the stereoisomeric composition of the derived phytanic acids as well as of the ester-bound phytanic acid was determined by open-tubular gas-liquid chromatography of the corresponding methyl esters on butanediolsuccinate polyester. Only the 3 R ,7 R ,11 R -isomer of phytanic acid was detected in each of the phytanate samples, indicating that these phytanyl chains in the Dead Sea sediments are most likely derived from extremely halophilic bacteria rather than from phytol of chlorophyll origin. These findings also provide further evidence that the mixtures of RRR and SRR -phytanic acids previously isolated from organic-rich shales were most likely derived from the phytyl chain in chlorophyll.

Geochimica et Cosmochimica Acta↗
USGS1984

Stereochemical studies of acyclic isoprenoids—XII. Lipids of methanogenic bacteria and possible contributions to sediments

Abundant volatile lipids of Methanobacterium thermoautotrophicum and Methanosarcina barkeri include isoprenoid hydrocarbons (≤ C 30 ), and C 15 , C 20 and C 25 isoprenoid alcohols. M. barkeri contains 2,6,10,15,19-pentamethyleicosane, whose relative stereochemistry is the same as found in marine sediments, indicating that it is a marker of methanogenic activity. The C 20 , C 30 and C 25 alkenes in M. thermoautotrophicum also have a preferred sterochemistry; the latter have the 2,6,10,14,18-pentamethyleicosanyl skeleton, suggesting that the alkane in marine sediments may derive from methanogens. The stereochemistry of squalane in a marine sediment is also compatible with an origin in methanogens; in contrast, the stereochemistry of pristane in M. thermoautotrophicum indicates a fossil fuel contaminant origin, suggesting that this and certain other alkanes reported in archaebacteria might also be of contaminant origin. There is, therefore, little evidence at present that the pristane in immature marine sediments originates in methanogens. The C 15 and C 20 saturated alcohols in M. thermoautotrophicum have mainly the all-R configuration. If this is generally true for methanogens, the C 20 alcohol in the Messel shale may originate mainly from methanogens, whereas that in the Green River shale may originate mainly from photosynthetic organisms.

Organic Geochemistry↗
USGS1994

Lipids and proteins in the Rathke's gland secretions of the North American mud turtle ( Kinosternon subrubrum )

Lipids and proteins in the Rathke's gland secretions of the North American mud turtle ( Kinosternon subrubrum , Kinosternidae) were analyzed by gas chromatography-mass spectrometry (GC-MS) and SDS-polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Analysis by GC-MS indicates 2,3-dihydroxypropanal and C 3 –C 24 free or esterified fatty acids. Analysis by SDS-PAGE indicates a major protein component with an approximate molecular mass of 60 kDa and minor components ranging from ca. 23 to 34 kDa. The major component of K. subrubrum glandular secretions exhibits a mobility that matches that of the Kemp's ridley sea turtle ( Lepidochelys kempi , Cheloniidae), suggesting that these proteins are evolutionarily conserved.

Comparative Biochemistry and Physiology, Part B: C↗
USGS2009

Organochlorine concentrations in bald eagles: Brain/body lipid relations and hazard evaluation

Residue levels of 12 organochlorine compounds found In the brains of bald eagles can be predicted from the corresponding concentrations in the carcass when expressed on a hexane‐extractable lipid basis. The compounds varied by a factor of about 3 in the degree to which they accumulated In the brain. An understanding of these relations enhances our ability to assess the toxic hazards of environmental contamination.

Journal of Toxicology and Environmental Health↗
USGS1989

Hepatic glutathione metabolism and lipid peroxidation in response to excess dietary selenomethionine and selenite in mallard ducklings

Selenium from selenomethionine accumulated in a dose-dependent manner in the liver, resulting in a decrease in hepatic-reduced glutathione with a corresponding decrease in total hepatic thiols. There was a dose-dependent increase in the oxidized to reduced glutathione ratio, and an increase in lipid peroxidation. These findings indicate that Se in the diet at 10 ppm and higher causes significant sublethal alterations in mallard ducklings, and 20-40 ppm causes significant hepatotoxicity.

Journal of Toxicology and Environmental Health↗
USGS2006

Co-oxidation of the sulfur-containing amino acids in an autoxidizing lipid system

Oxidation of the sulfur amino acids by autoxidizing lipids was studied in a model system consisting of an amino acid dispersed in cold-pressed, molecularly distilled menhaden oil (20&ndash;80% w/w). Under all conditions investigated, cysteine was oxidized completely to cystine. Preliminary results suggest that at 110&deg;C the oxidation follows first-order kinetics for at least the first 8 hr. A specific reaction rate constant of 0.25 per hour was calculated. When fatty acids were added to the system, cystine was oxidized to its thiosulfinate ester. When the fatty acid-cystine ratio was 1:2, oxidation of cystine was a maximum. No oxidation of cystine occurred unless either a fatty acid, volatile organic acid, or ethanol was added. Under the conditions investigated, methionine was not oxidized to either its sulfoxide or its sulfone.

Journal of Food Science↗
USGS2004

Overview and comparison of lipid-containing semipermeable membrane devices and oysters (Crassostrea gigas) for assessing organic chemical exposure

We performed 20-d, flow-through exposures of lipid-containing semipermeable membrane devices (SPMDs) and Pacific oysters ( Crassostrea gigas ) to three concentrations (nominally 10, 100, and 250 ng/L) of a diverse mixture of polycyclic aromatic hydrocarbons (PAHs). Exposure water was seawater free of particulates larger than 0.1 μm. The results of these controlled laboratory studies demonstrated that SPMDs and oysters concentrate the same chemicals but that the relative amounts accumulated are different. For oysters, the 20-d mean (across treatments) concentration factors (CFs) of test compounds with log K ow ≤ 4.8 were much lower (4.0- to 20-fold lower) than those of the same compounds in SPMDs. In contrast, the 20-d CFs of PAHs with log K ow ≥ 5.6 in oysters from the low-level treatment were higher than the corresponding CFs for SPMDs. The CFs of these compounds in oysters from the low-level treatment ranged from approximately 3.0- to 13-fold higher than those in oysters from the high-level treatment. This physiologically mediated difference in oyster CFs appears to be linked to active feeding in the low-level treatment and to apparent toxicity-induced cessation of feeding (i.e., valve closure) in the high-level treatment. Because CFs for these compounds in oysters were not independent of exposure concentrations, it follows that tissue levels were not proportional to exposure concentration. However, both sampling approaches have advantages and disadvantages, and the appropriateness of their use depends on the goals of a given study.

Environmental Toxicology and Chemistry↗
USGS1985

Organochlorine concentrations, whole body weights, and lipid content of black skimmers wintering in Mexico and in south Texas, 1983

Since 1978, a large proportion of the black skimmers (Rynchops niger) nesting along the Texas coast have had high concentrations of DDE in their eggs. Of 284 eggs collected from 5 sites during 1978-81, 99.5% contained detectable (> 0.i0 ppm) w levels of DDE, ranging up to 86 ppm wet-weight; 36% of the eggs contained > i0 ppm DDE (White et al., 1984). During the 4-year period, geometric mean concentrations of DDE remained strikingly similar, with no significant decline in egg contaminant levels. The sources of DDE contamination in skimmers are unknown. Recoveries of juvenile skimmers banded in Texas, Louisiana, and Mississippi indicate that a large proportion of the birds (60%) spend the winter on the east and west coasts of Mexico. Therefore, it is possible that the DDE exposure to Texas skimmers occurs in Mexico during the winter, although some birds remain along the Gulf Coast year-round.\ This study was conducted to determine the degree of DDE and other organochlorine contamination in black skimmers and their food items from sites in Mexico and Texas, and to statistically compare residue concentrations and body condition in individuals from the 2 areas.

Texas, Veracruz↗
USGS1973

Pesticide residues in eggs of wild birds: Adjustment for loss of moisture and lipid

Eggs of wild birds collected for the purpose of measuring concentrations of pesticides or other pollutants vary from nearly fresh to nearly dry so that objective comparisons cannot be made on the basis of weight of the contents at the time of collection. Residue concentrations in the nearly dry eggs can be greatly exaggerated by this artifact. Valid interpretation of residue data depends upon compensation for these losses. A method is presented for making adjustments on the basis of volume of the egg, and formulas are derived for estimating the volume of eggs of eagles, ospreys, and pelicans from egg measurements. The possibility of adjustments on the basis of percentage of moisture, solids, or fat in fresh eggs is discussed also.

Bulletin of Environmental Contamination and Toxico↗