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At least 109 records · Page 6Linked to original sources
USGS1989

Divergent effects of postmortem ambient temperature on organophosphorus- and carbamate-inhibited brain cholinesterase activity in birds

Time- and temperature-dependent postmortem changes in inhibited brain cholinesterase (ChE) activity may confound diagnosis of field poisoning of wildlife by anticholinesterase pesticide. Carbamate-inhibited ChE activity may return to normal within 1 to 2 days of exposure of intact carcass to moderate ambient temperature (18-32C). Organophosphorus-inhibited ChE activity becomes more depressed over the same time. Uninhibited ChE activity was resilient to above freezing temperature to 32C for 1 day and 25C for 3 days. Carbamate- and organophosphorus-inhibited ChE can be separated by incubation of homogenate for 1 hour at physiological temperatures; carbamylated ChE can be readily reactivated while phosphorylated ChE cannot.

Pesticide Biochemistry and Physiology↗
USGS1992

Suppression of guinea pig ileum induced contractility by plasma albumin of hibernators

Previous studies suggest that hibernation may be regulated by internal opioids and that the putative “hibernation induction trigger” (HIT) may itself be an opioid. This study examined the effect of plasma albumin (known to bind HIT) on induced contractility of the guinea pig ileum muscle strip. Morphine (400 nM) depressed contractility and 100 nM naloxone restored it. Ten milligrams of lyophilized plasma albumin fractions from hibernating ground squirrels, woodchucks, black bears, and polar bears produced similar inhibition, with partial reversal by naloxone. Five hundredths mg of d-Ala2-d-Leu5-enkephalin (DADLE) also inhibited contractility and naloxone reversed it. Conclusions are that hibernating individuals of these species contain an HIT substance that is opioid in nature and summer animals do not; an endogenous opioid similar to leu-enkephalin may be the HIT compound or give rise to it.

Pharmacology Biochemistry and Behavior↗
USGS1976

Influence of water temperature on gill sodium, potassium-stimulated ATPase activity in juvenile coho salmon (Oncorhynchus kisutch)

1. Gill sodium, potassium-stimulated ATPase activity was determined from December to July in gills of yearling coho salmon ( Oncorhynchus kisutch ) maintained at four temperatures, 6, 10, 15 and 20°C. 2. Compared to fish held at 6°C, elevation in ATPase activity and the associated parr-smolt transformation were accelerated in fish at 10 and 15°C whereas animals at 20°C experienced at best only a transitory elevation in activity. 3. Fish transferred from one temperature to another developed ATPase activities characteristic of fish residing at temperatures to which they were transferred. 4. Cold water (6°C) tended to preserve the elevated ATPase activity while higher temperatures (10 and 15°C) caused decreases after an initial accelerated increase.

Comparative Biochemistry and Physiology, Part A: P↗
USGS1978

Indocyanine green: A test of hepatic function and a measure of plasma volume in the duck

1. The exponential removal of ICG from the plasma by the mallard duck liver made possible the measurement of fractional dye clearance (K), plasma volume (PV) and plasma clearance (PC). 2. Values obtained for K (14.9%/min), PV (39.2 ml/kg) and PC (5.8 ml/min per kg) agreed with those obtained by other techniques used in a number of species. 3. Sex did not affect the removal of ICG by the liver. However, increases in K, PV and PC were noted in hen mallards in laying condition. 4. The data should prove useful as baseline values for physiological and pathological studies on the avian liver

Comparative Biochemistry and Physiology, Part A: P↗
USGS1980

The influence of hunger on meal to pellet intervals in barred owls

1. Barred owls fed at a sub-maintenance (SM) level had significantly (P < 0.01) longer meal to pellet intervals (MPI)/g eaten/kg body weight (BW) than those fed at an above maintenance (AM) level; MPI/g per kg for owls fed at a maintenance (M) level was intermediate but significantly (P < 0.01) different from both SM and AM. 2. During SM feeding, MPI/g per kg gradually increased. 3. The proportion of a meal occurring in a pellet was less in “hungry” owls whether losing weight (SM) or gaining (AM) as compared to owls maintaining their normal body weight (M). 4. SM fed owls appear to be able to increase digestion time as well as thoroughness of digestion.

Comparative Biochemistry and Physiology, Part A: P↗
USGS1983

The bile acid composition of crane gallbladder bile

1. The biliary bile acids of the whooping crane ( Grus americana ) and the Florida sandhill crane ( G. canadensis pratensis ) have been examined. 2. Cholic acid (CA), chenodeoxycholic acid (CDOCA) and lithocholic acid were found in bile from both species of these North American cranes. 3. CDOCA and CA were the primary bile acids in both species, together constituting 70% or more of the bile acids by weight. 4. The primary bile acids of cranes appear to be the same as those that have been identified in other avian species.

Comparative Biochemistry and Physiology, Part A: P↗
USGS1984

Composition and energy contents of mature inshore spawning capelin ( Mallotus villosus ): Implications for seabird predators

1. Lipid levels of capelin are highest in late fall and lowest during the summer spawning season; protein levels are constant at 13–14% body wt throughout the year. 2. Ovid females contained significantly more lipid and protein and less water and had higher energy densities than males and spent females. 3. Surgically-removed egg masses made up 34.2 ± 10.3% female body wt and were very similar in composition and energy density to gravid females, differing from spent females and males in similar respects. Owing to the ovarian development of females, sexes differ in energy density only during the spawning season. 4. Sexes were similar in amino acid composition. Analysis of capelin and three other seabird forage species revealed that isoleucine levels were lower than minimum avian maintenance and growth requirements. 5. Implications for the foraging behaviour and food preferences of diving seabird predators (murres, puffins) are discussed

Comparative Biochemistry and Physiology, Part A: M↗
USGS1984

Effects of dietary excesses of branched-chain amino acids on the metabolism and tissue composition of lake trout ( Salvelinus namaycush )

1. Excesses of either leucine, isoleucine or valine were fed in separate experiments to determine if the branched-chain amino acid antagonism reported in other animals occur in trout ( Salvelinus namaycush ). 2. Parameters measured include growth rate, feed utilization efficiency, plasma and muscle-free amino acids, carcass composition and branched-chain amino acid aminotransferase. 3. Dietary excesses of leucine or isoleucine caused an increase in the valine requirement. 4. The inability of leucine and isoleucine supplementations to ameliorate the effects of excess dietary valine are interpreted as a valine toxicity rather than an antagonism.

Comparative Biochemistry and Physiology, Part A: P↗
USGS1986

Response of rainbow trout to source and level of supplemental dietary methionine

1. Methionine and total sulfur amino acid (TSAA) requirements of rainbow trout ( Salmo gairdneri ) were investigated by feeding graded isosulfurous levels of l - and dl -methionine, l -cystine, and the free acid and calcium forms of methionine hydroxy analog (MHA). 2. Added cystine did not promote growth, survival or prevent cataracts. 3. l -methionine produced fastest growth, followed by dl -methionine, CaMHA and free acid MHA. 4. Trout fed CaMHA gained 85.7 and 92.3% as much as those fed l -methionine and dl -methionine. 5. Within each experiment, the level of L-methionine isomer that prevented cataracts was constant (1.86 g/100g protein in experiment (1), 1.45 in experiment (2) and was lower than for maximum growth (2.89 and 2.15 g) regardless of methionine source.

Comparative Biochemistry and Physiology, Part A: P↗
USGS1990

Whole body and tissue blood volumes of two strains of rainbow trout ( Oncorhynchus mykiss )

1. Estimates of apparent packed cell, plasma and total blood volumes for the whole body and for 13 selected tissues were compared between Kamloops and Wytheville strains of rainbow trout ( Oncorhynchus mykiss ) by the simultaneous injection of two vascular tracers, radiolabeled trout erythrocytes ( 51 Cr-RBC) and radioiodated bovine serum albumin ( 125 I-BSA). 2. Whole body total blood volume, plasma volume and packed cell volume were slightly, but not significantly greater in the Wytheville trout, whereas, the apparent plasma volumes and total blood volumes in 4 of 13 tissues were significantly greater in the Kamloops strain. 3. Differences were most pronounced in highly perfused organs, such as the liver and kidney and in organs of digestion such as the stomach and intestines. 4. Differences in blood volumes between the two strains may be related to the greater permeability of the vascular membranes in the Kamloops strain fish.

Comparative Biochemistry and Physiology, Part A: M↗
USGS1991

Male sex steroids and hormonal control of male courtship behavior in the yellow-bellied slider turtle, Trachemys scripta

Survey of androgens and estrogens in serum, liver and testes of male yellow-bellied slider turtles, Trachemys (= Pseudemys ) scripta , a species exhibiting dissociated gametogenesis age-dependent melanism, revealed the presence of numerous androgen precursors, androgens, androgen metabolites, and estrogens in quantities varying with season, tissue, and male coloration. The most commonly found and abundant androgens in all males were dehydroepiandrosterone (DHEA) and androstenedione, which were present at significantly higher levels in testes than in serum or liver. Epitestosterone was found in the serum and liver of only melanistic males; testosterone was only rarely recovered. Behavioral testing of castrated male turtles implanted with various androgens, as well as intact and sham-operated controls, revealed that melanistic males courted more frequently than nonmelanistic males, and that exogenous testosterone was most effective in inducing courtship behavior in castrated males.

Comparative Biochemistry and Physiology, Part A: M↗
USGS1993

Effects of salinity on chloride cells and Na+ K+-ATPase activity in the teleost Gillchthys mirabilis

1. Longjawed mudsuckers, Gillichthys mirabilis , in 30ppt seawater (SW) were transferred to 1.5, 30 and 60ppt SW. 2. In the first 1–3 days after transfer, plasma chloride level and plasma osmolarity rose in the 60ppt SW fish, and decreased in the 1.5ppt SW fish. 3. By day 21, however, plasma chloride and osmolarity were at or near the levels seen in the controls (30ppt). 4. Branchial and jawskin Na + , K + -ATPase activities were high in all salinities, and did not differ significantly among treatments. 5. The vital fluorescent stains DASPEI and anthroylouabain were used to detect mitochondria and Na + , K + -ATPase, respectively, in chloride cells. 6. Both stains indicated that jawskin chloride cell density did not differ among treatment groups. 7. In contrast, chloride cell size increased significantly with increasing salinity. 8. The chloride cells of fish in 60 ppt SW were noticeably angular in outline, whereas those of both the 1.5 and 30ppt SW fish were circular. 9. The results are discussed in relation to the ion transport requirements encountered in the intertidal habitat of the mudsucker.

Comparative Biochemistry and Physiology, Part A: P↗
USGS1995

Protein retention and liver aminotransferase activities in Atlantic salmon fed diets containing different energy sources

Atlantic salmon ( Salmo salar ) fingerlings (14.4 g) were fed diets containing either glucose, dextrin, raw corn starch and lipid, or a high protein U.S. Fish and Wildlife Service open-formula diet (ASD2-30) for 12 weeks. Significant differences in weight gain and feed: gain ratio were not observed among salmon fed the diets containing glucose, dextrin or ASD2-30. Diets containing dextrin and glucose supported greater protein retention and reduction in alanine aminotransferase activity than the other diets. Activity of aspartate aminotransferase was not affected by the dietary treatment. Protein retention correlated highly with alanine aminotransferase activity.

Comparative Biochemistry and Physiology, Part A: P↗
USGS1996

Kangaroo rat bone compared to white rat bone after short-term disuse and exercise

Kangaroo rats ( Dipodomys ordii ) were used to study the effects of confinement on mechanical properties of bone with a long range objective of proposing an alternative to the white rat model for the study of disuse osteoporosis. Kangaroo rats exhibit bipedal locomotion, which subjects their limbs to substantial accelerative forces in addition to the normal stress of weight bearing. We subjected groups of kangaroo rats and white rats ( Rattus norvegicus ) to one of two confinement treatments or to an exercise regime; animals were exercised at a rate calculated to replicate their (respective) daily exercise patterns. White laboratory rats were used as the comparison because they are currently the accepted model used in the study of disuse osteoporosis. After 6 weeks of treatment, rats were killed and the long bones of their hind limbs were tested mechanically and examined for histomorphometric changes. We found that kangaroo rats held in confinement had less ash content in their hind limbs than exercised kangaroo rats. In general, treated kangaroo rats showed morphometric and mechanical bone deterioration compared to controls and exercised kangaroo rats appeared to have slightly “stronger” bones than confined animals. White rats exhibited no significant differences between treatments. These preliminary results suggest that kangaroo rats may be an effective model in the study of disuse osteoporosis.

Comparative Biochemistry and Physiology, Part A: P↗
USGS1977

Effect on tricaine methanesulfonate (MS-222) on hematocrit values in rainbow trout ( Salmo gairdneri )

1. Anesthesia of rainbow trout ( Salmo gairdneri ) with 70 ppm tricaine methanesulfonate (MS-222) for 3-9 min resulted in a linear increase in hematocrit. 2. Handling of unanesthetized trout caused a higher and more variable hematocrit reading than did exposure to MS-222 for up to 3 min. 3. The range and standard error of hematocrit readings was smallest in trout treated with MS-222 for 1 min.

Comparative Biochemistry and Physiology, Part C: C↗
USGS1978

Six different plasma enzymes in bald eagles ( Haliaeetus leucocephalus ) and their usefulness in pathological diagnosis

1. Activities of creatine phosphokinase, glutamic oxalacetic transaminase, glutamic pyruvic transaminase, lactate dehydrogenase, fructose diphosphate aldolase and cholinesterase were measured in plasma of bald eagles. 2. There were no sex differences in the plasma enzyme activities. 3. An acute dieldrin dosage (10 mg/kg) of a female bald eagle resulted in 400% increases in activities of plasma creatine phosphokinase and glutamic oxalacetic transaminase and 250% increases in activities of lactate dehydrogenase and glutamic pyruvic transaminase. 4. At 11 days post-dosage all but one of the plasma enzyme activities had returned to normal; glutamic oxalacetic transaminase activity remained 100% above pre-dosage values. 5. Plasma enzyme assays constitute a non-destrcutive procedure that can be used in valuable wildlife species to screen for the presence and prevalence of environmental contaminants.

Comparative Biochemistry and Physiology, Part C: C↗
USGS1979

Allantoinase in lake trout ( Salvelinus namaycush ): In vitro effects of PCBs, DDT and metals

1. Allantoinase, an enzyme in the purine-urea cycle, was found in livers of Salvelinus namaycush (Osteichthyes: Salmoniformes). 2. The enzyme was active from pH 6.6 to 8.2 at 37°C and from pH 7.4 to 9.0 at 10°C and had an Arrhenius energy was activation of 11.0 kcal/mol and a temperature quotient of 2.0. The K m of the enzyme homogenate was 8.4 mM allantoin. 3. The concentrations of inorganic metals at which 50% inhibition occurred during in vitro exposure were 6.0 mg/l Cu 2+ , 6.7 mg/l Cd 2+ , 34 mg/l Hg 2+ and 52 mg/l Pb 2+ . The in vitro sensitivity to PCBs, DDT and DDE and kinetics in the presence of metals were determined. 4. Allantoinase activity was negatively correlated with body length for fish from Lake Michigan but not from Lake Superior or the laboratory.

Comparative Biochemistry and Physiology, Part C: C↗
USGS1980

Effects of petroleum hydrocarbons on hepatic function in the duck

1. The indocyanine green dye clearance test for hepatic function was determined in mallard ducks before and during the chronic ingestion (7 months) of representative paraffinic or aromatic petroleum hydrocarbons (PH). 2. No mortality or visible symptoms of toxicity occurred in any of the tests. Ingestion of 4000 ppm aromatic PH produced significant increases in liver (25%), plasma clearance of indocyanine green (33%) and hepatic blood flow (30%). 3. Although the aromatics elicited a greater hepatic stress response than the paraffins, the ducks tolerated high concentrations of PH for extended periods.

Comparative Biochemistry and Physiology, Part C: C↗