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G. H. Heinz

Publications and source records attributed to G. H. Heinz.

At least 55 records · Page 3Linked to original sources
USGS1993

Selenium accumulation and loss in mallard eggs

Five female mallards (Anas platyrhynchos) that had just started egg laying were first fed a diet containing 15 ppm selenium in the form of selenomethionine for 20 d and then an untreated diet for 20 d. Selenium levels in eggs peaked (to about 13-20 ppm) in about two weeks on the treated diet and leveled off at a low level (< 5 ppm) after about 10 d back on the untreated diet. Selenium levels in egg whites responded faster than levels in yolks to the females' consumption of treated and untreated diets. References

Environmental Toxicology and Chemistry↗
USGS1993

Reproduction of mallards following overwinter exposure to selenium

Forty pairs of mallards ( Anas platyrhynchos ) were fed 15 ppm selenium as selenomethionine for about 21 weeks during winter. Twenty pairs served as controls. At the end of 21 weeks, which coincided with the onset of the reproductive season, selenium treatment was ended. Four birds died while on selenium treatment. Treated females lost weight, and their egg-laying was delayed. Hatching success of some of the first eggs laid by selenium-treated females was lower than that of controls, and a few of these early eggs contained deformed embryos, but, after a period of about two weeks off the selenium-treated diet, reproductive success returned to a level comparable with that of controls. The return to normal reproductive success was the result of a corresponding decrease in selenium concentrations in eggs once selenium treatment ended.

Environmental Pollution↗
USGS1992

Status and Assessment of Chesapeake Bay Wildlife Contamination

As an integral component of its priority setting process, the Chesapeake Bay Program`s Toxics Subcommittee has sought the expertise of Chesapeake Bay researchers and managers in developing a series of Chesapeake Bay toxics status and assessment papers. In the report, evidence for historical and current contaminant effects on key bird species, mammals, reptiles and amphibians which inhabit the Chesapeake Bay basin is examined. For each group of wildlife species, a general overview of effects caused by specific toxic substances is followed by detailed accounts of contaminant effects on selected species. Sponsored by Environmental Protection Agency, Annapolis, MD. Chesapeake Bay Program.

Environmental Protection Agency, Chesapeake Bay Pr↗
USGS1991

Subchronic hepatotoxicity of selenomethionine ingestion in mallard ducks

Twoyearold male mallards (Anas platyrhynchos) received a control diet (0.2 ppm Se) or diets containing 1, 2, 4, 8, 16, or 32 ppm Se as selenomethionine for 14 wk. Se accumulated readily in the liver in a dosedependent manner, reaching a mean concentration of 29 ppm (wet weight) in the 32 ppm group. Dietary Se of 2 ppm or greater increased plasma glutathione peroxidase activity. Mortality (10%) and histopathological effects, including bile duct hyperplasia and hemosiderin pigmentation of the liver and spleen, occurred in the 32 ppm group. These histopathological effects were accompanied by lower hemoglobin concentrations (16 and 32 ppm groups) and hematocrit (32 ppm group), and elevated plasma alkaline phosphatase activity (32 ppm group) indicative of cholestatic liver inJury. Other manifestations of hepatotoxicity included significant linear dose responses for hepatic oxidized glutathione (GSSG) concentrations and ratio of GSSG to reduced glutathione (GSH). Means for both of these responses differed from controls in groups receiving 832 ppm Se. Mean hepatic GSH and malondialdehyde (a measure of lipid peroxidation) concentrations were significantly elevated in the 16 and 32 ppm groups. Subchronic effects of selenomethionine, which occurs in vegetation, are of particular interest with respect to the health of wild aquatic birds in seleniferous locations.

Journal of Toxicology and Environmental Health↗
USGS1990

Avoidance of selenium-treated food by mallards

Adult, male mallards ( Anas platyrhynchos ) were given a choice between a control diet and a diet containing 5, 10 or 20 ppm selenium as selenomethionine dissolved in water and mixed into the diet. At 10 and 20 ppm, selenium-treated diets were avoided. Avoidance appeared to be caused by a conditioned response, probably to illness caused by the selenium and not to an aversion to the taste of the selenium.

Environmental Toxicology and Chemistry↗
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↗
USGS1988

Reproduction in black-crowned night-herons fed selenium

Agricultural and industrial practices can produce wastewater that contains high concentrations of selenium, a naturally-occurring trace element. Selenium entering aquatic systems through wastewater inflow can accumulate in aquatic food chains to levels that may be toxic to fish and wildlife species. Mallard reproduction is known to be adversely affected by 10 ppm selenium in the diet (containing 7–10 percent moisture, in the form of selenomethionine); however, hatching success of eggs laid by black-crowned night-herons fed a 10 ppm selenium diet, as selenomethionine, in this study was not different from eggs laid by herons fed an unsupplemented diet (0.1 ppm selenium). Organ weights, hemoglobin concentrations, hematocrits, eggshell thickness, and shell thickness did not differ between controls and herons receiving 10 ppm selenium. Developmental malformations commonly associated with selenium exposure in other birds were not observed in heron embryos or hatchlings in the 10 ppm group. However, three-day-old hatchlings from herons fed 10 ppm selenium had shorter radius-ulna and femur lengths and higher liver malondialdehyde concentrations than controls. Selenium residues in heron eggs were lower than those reported in mallards fed the same amount of selenium. Results of this study suggest that herons are less sensitive to the toxic effects of selenium than mallards. Other hypotheses are also considered to explain the different responses of the two species.

Lake and Reservoir Management↗
USGS1988

Embryotoxic and teratogenic effects of selenium in the diet of mallards

Mallards (Anas platyrhynchos) were fed a control diet, diets containing 1, 5, 10, or 25 ppm Se as sodium selenite, or a diet containing 10 ppm Se as seleno-DL-methionine in the first of two experiments. Selenium at 10 ppm as selenomethionine or 25 ppm as sodium selenite caused a 40-44% decrease in the total number of eggs that hatched compared to controls. Selenium at 25 ppm (sodium selenite) resulted in a 19% decrease in mean embryonic weight at 18 d of incubation, accompanied by a 6% decrease in crown-rump length. Ten parts per million Se as selenomethionine was more teratogenic than sodium selenite at 25 ppm. Selenomethionine (10 ppm Se) resulted in an incidence of 13.1% malformations that were often multiple, whereas sodium selenite (10 and 25 ppm Se) resulted in 3.6 and 4.2% malformations. The teratogenicity of selenomethionine was confirmed in a second experiment in which mallards received 1, 2, 4, 8, or 16 ppm Se as selenomethionine, resulting in 0.9, 0.5, 1.4, 6.8, and 67.9% malformations, respectively. These malformations included hydrocephaly, microphthalmia, lower bill defects, and foot defects with ectrodactyly. Both forms of selenium increased the incidence of edema and stunted embryonic growth. Selenomethionine (10 ppm Se) resulted in a significant increase of approximately 40% in plasma glutathione peroxidase activity and a 70% increase in sorbitol dehydrogenase activity (indicative of hepatotoxicity) in hatchlings. Sodium selenite (25 ppm Se) resulted in fourfold elevation in plasma uric acid concentration, indicative of renal alteration. Selenomethionine accumulated much better in eggs than did sodium selenite. These findings indicate that selenomethionine is considerably more teratogenic and generally more embryotoxic than sodium selenite, probably due to higher uptake of selenomethionine.

Journal of Toxicology and Environmental Health↗
USGS1987

Behavior of mallard ducklings from adults exposed to selenium

Pairs of adult mallards ( Anas platyrhynchos ) were fed a control diet or a diet containing 1, 2, 4 or 8 ppm selenium in the form of seleno-DL-methionine. Ducklings from these pairs were fed an untreated diet from hatching through 6 d of age, at which time their avoidance of a fright stimulus was tested. Selenium had no effect on the ducklings' response to the fright stimulus.

Environmental Toxicology and Chemistry↗
USGS1987

Reproduction in mallards fed selenium

Mallards (Anas platyrhynchos) were fed diets containing 1, 5, 10, 25 or 100 ppm selenium as sodium selenite, a diet containing 10 ppm selenium as seleno-DL-methionine or a control diet. There were no effects of 1, 5 or 10 ppm selenium as sodium selenite on either weight or survival of adults or on reproductive success, and there did not appear to be a dose-response relationship at these lower levels. The 100 ppm selenium diet killed 11 of 12 adults; one adult male fed 25 ppm selenium died. Selenium at 25 and 100 ppm caused weight loss in adults. Females fed 25 ppm selenium took longer to begin laying eggs and intervals between eggs were longer than in females in other treatment groups. Hatching success appeared to be reduced in birds fed 10 ppm selenium as selenomethionine, but the reduction was not statistically significant. The survival of ducklings and the mean number of 21-d-old ducklings produced per female were reduced in the 25 ppm selenium as sodium selenite group and the 10 ppm selenium as selenomethionine group. Egg weights were not affected by any selenium treatment, but 25 ppm selenium lowered the Ratcliffe Index. Duckling weights at hatching and at 21 d of age were reduced 28 and 36%, respectively, in birds fed 25 ppm selenium, as compared with controls. Body weights measured on day 21 were lower for ducklings fed 10 ppm selenium as selenomethionine than in some other groups. Selenium in concentrations of 10 and 25 ppm as sodium selenite caused mainly embryotoxic effects, whereas 10 ppm as selenomethionine was more teratogenic, causing hydrocephaly, bill defects, eye defects (microphthalmia and anophthalmia) and foot and toe defects, including ectrodactyly. Selenomethionine was much more readily taken up by mallards and passed into their eggs than was sodium selenite, and a greater proportion of the selenium in the eggs ended up in the white when selenomethionine was fed. Adult males accumulated more selenium than did females, probably because of the females' ability to eliminate selenium in their eggs.

Environmental Toxicology and Chemistry↗
USGS1987

Mercury accumulation in mallards fed methylmercury with or without added DDE

Adult female mallards (Anas platyrhynchos) were fed a control diet or diets containing 1 ppm methylmercury chloride, 5 ppm methylmercury chloride, 1 ppm methylmercury chloride plus 5 ppm DDE, or 5 ppm methylmercury chloride plus 5 ppm DDE. The presence of DDE in the diet did not affect retention of mercury in breast muscle or eggs. There was a good correlation between the levels of mercury in the breast muscle of females and their eggs, and this correlation was unaffected by the presence of DDE in the diet. This correlation suggests that one could predict mercury levels in female mallards in the field when only eggs have been collected and vice versa.

Environmental Research↗
USGS1986

Differences in mortality among bobwhite fed methylmercury chloride dissolved in various carriers

Twelve-day-old bobwhite chicks were fed a diet containing 0, 5.4 or 20 ppm methylmercury chloride. The methylmercury chloride was added to the diet either in a dry, pulverized form or dissolved in acetone, propylene glycol or corn oil. Mortality was measured for 6 weeks, and samples of liver were saved for mercury analysis. Mortality was significantly lower in birds fed 20 ppm methylmercury chloride when acetone was the solvent. The reduced mortality could not be explained by effects of acetone on dietary level of mercury or on uptake of mercury into the body.

Environmental Toxicology and Chemistry↗
USGS1986

Reproduction and health of mallards fed endrin

Concentrations of 0, 1 and 3 ppm endrin in dry duck mash were fed to mallards ( Anas platyrhynchos ) starting in December, and health and reproduction were measured the following spring and summer. One male fed 3 ppm endrin died with 2.0 ppm endrin (wet weight), a diagnostically lethal level, in its brain. Birds fed 1 ppm endrin reproduced as well as, if not better than, controls. Birds fed 1 ppm endrin had significantly greater hatching success of fertile eggs than did those fed 0 or 3 ppm, and their clutches hatched significantly earlier than did those of birds fed 3 ppm. Mallards fed 3 ppm endrin appeared to reproduce more poorly than controls, but this finding must be regarded with caution because the results of statistical tests often were not significant. Endrin accumulated in eggs to a mean of 1.1 and 2.9 ppm (wet weight) when fed to hens at 1 and 3 ppm. The concentration of endrin in the carcasses of adults was similar to that in eggs, but the concentration in the fat of adults was about 4 to 7 times higher than in eggs.

Environmental Toxicology and Chemistry↗
USGS1985

Toxicity of abate® 4E (temephos) in mallard ducklings and the influence of cold

Diets mixed to contain 0, 0.1, 1.0, 10 and 100 ppm temephos (determined chemically to contain less than 0.5, less than 0.5, 0.89, 6.0 and 59 ppm temephos, respectively) in an Abate® 4E formulation, were fed to mallard (Anas platyrhynchos) ducklings for 7 d. During this period, half of the ducklings in each dietary treatment group were housed in a heated brooder (39 to 41 °C) and half were housed in an unheated brooder (10 to 18°C). Mortality in all dietary groups in the unheated brooder was higher than in the heated brooder. High temephos-related mortality occurred in the 100 ppm group in the unheated brooder but not in any other diet-temperature groups. Ingestion of the 100 ppm temephos diet inhibited plasma Cholinesterase (ChE) activity and elevated plasma corticosterone concentration and creatine phosphokinase activity, but other selected plasma chemistries were not affected in a dose-related manner. Brain ChE activity was depressed only in the 100 ppm dietary groups; maximum inhibition of brain ChE activity was 48%. These findings suggest that diets containing up to 10 ppm temephos do not directly affect duckling survival during the first week of life and that the toxicity of 100 ppm temephos is markedly enhanced by cold.

Environmental Toxicology and Chemistry↗
USGS1985

Contaminant levels in colonial waterbirds from Green Bay and Lake Michigan, 1975–80

Residues of organochlorine pesticides, polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polychlorinated styrenes (PCSs), and mercury were measured in the eggs of 10 species of colonial waterbirds nesting in areas around Green Bay or Lake Michigan from 1975 to 1980. Residues also were measured in the carcasses and brains of black-crowned night-herons ( Nycticorax nycticorax ). The highest residues were of PCBs, DDE, mercury, and dieldrin; for some species, levels of these chemicals possibly were high enough to have caused reproductive effects. Other organochlorine pesticides were found at low levels. Only trace amounts of PCSs and PBBs were found. Eggs of herring gulls ( Larus argentatus ) collected in 1977 from an island in Lake Michigan contained an average of 100 ppm PCBs and 33 ppm DDE; this was the most-contaminated species. Cattle egrets ( Bubulcus ibis ), the only bird that is not a fish eater, contained only small quantities of DDE and mercury.

Environmental Monitoring and Assessment↗
USGS1985

Lethal and behavioral effects of chlordimeform in bobwhite

The 7-day LC50 of chlordimeform to bobwhite (Colinus virginianus) chicks was 2835 ppm (95% CI = 2169-3705 ppm). Bobwhite chicks fed 1000 ppm (~ LC4) chlordimeform for 7 days ate less, weighed less, travelled farther from a fright stimulus in an avoidance test, and had significantly more groups make >10 light beam interruptions in an open-field test at 8 days of age than bobwhite fed 0, 1, 10, or 100 ppm chlordimeform (P< 0.05). Groups fed 100 ppm (P <0.05) and 1000 ppm (P = 0.11) for 7 days crossed more often from the shallow to deep side of a visual cliff at 8 days of age than birds fed lesser concentrations of chlordimeform. Bobwhites were retested at 15 days of age, after being fed untreated diets for 7 days following the chlordimeform diets. The 1000 ppm group still travelled greater distances in the avoidance test (P < 0.05). But open-field and visual cliff performances were similar to controls and other treatment groups. Chlordimeform concentrations causing behavioral abberations in bobwhite were appreciably higher than environmental concentrations following field applications of chlordimeform.

Toxicology↗