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At least 487 records · Page 27Linked to original sources
USGS1990

Mass-marking of otoliths of lake trout sac fry by temperature manipulation

The otoliths of 676,000 sac fry of lake trout Salvelinus namaycush in 1986, and of 1,100,000 in 1987, were marked by daily manipulation of water temperature. The fish were stocked into Lake Huron in the spring. Otolith marks consisted of groups of daily growth rings accentuated into recognizable patterns by steadily raising and lowering the temperature about 10 degrees C (from a base of 1-4 degrees C) over 14 h. In 1987, groups of marked and control fish were held for 6 months. The otoliths were removed from samples of the fish, embedded in epoxy, thin sectioned by grinding in the sagittal plane, etched, and viewed by using a combination of a compound microscope (400-1000x) and a video enhancement system. One or more readable otolith sections were obtained from 39 of a sample of 40 fish. Three independent readers examined 41 otoliths for marks and correctly classified the otoliths, with accuracies of 85, 98, and 100%, as being from marked or unmarked fish. The exact number of rings in a recognizable pattern sometimes differed from the number of temperature cycles to which the fish were exposed. Counts of daily rings within groups of six rings varied less than counts within groups of rings.

American Fisheries Society Symposium↗
USGS1988

Morphology of glochidia of Lampsilis higginsi (Bivalvia: Unionidae) compared with three related species

Glochidia of the endangered unionid mussel Lampsilis higginsi (Lea) are morphologically similar to those of several other species in the upper Mississippi River. Life history details, such as the timing of reproduction and identity of host fish, can be readily studied if the glochidia of L. higginsi can be distinguished from those of related species. Authors used light and scanning electron microscopy and statistical analyses of three shell measurements, shell length, shell height, and hinge length, to compare the glochidia of L. higginsi with those of L. radiata siliquoidea (Barnes), L. ventricosa (Barnes), and Ligumia recta (Lamarck). Glochidia of L. higginsi were differentiated by scanning electron microscopy on the basis of a combined examination of the position of the hinge ligament and the width of dorsal ridges, but were indistinguishable by light microscope examination or by statistical analyses of measurements.

American Malacological Bulletin↗
USGS1993

Diagnostic riddles

A bridled white-eye ( Zosterops conspicillata ) was captured in a mist net on the island of Saipan and transported to the island of Guam for an experimental study. Beginning on day three, it was immunosuppressed by intramuscular injections of dexamethasone. It was unexpectedly found dead on day 20, at which time it had lost 0.9 g (12.9% of initial body weight). Gross Pathology: Despite the weight loss, the white-eye was in good flesh, with abundant subcutaneous and visceral fat. The spleen was 3 x 11 mm, about 5 times normal size. The striatum of the forebrain was congested. There were no other lesions. Histopathology: There were microscopic abnormalities in skeletal muscle, brain, and gizzard (Figs. 1 and 2; Figure 2 is from a different white-eye which had virtually identical gizzard lesions).

Wildlife Disease Newsletter↗
USGS1999

Inclusion body disease of cranes

In March 1978, a previously unidentified herpesvirus was isolated at the National Wildlife Health Center (NWHC) from a die-off of captive cranes housed at the International Crane Foundation (ICF) in Baraboo, Wisconsin. Serological testing of this virus against other previously isolated avian herpesviruses does not result in cross-reactions, thereby supporting this agent’s status as a distinctly new virus. The NWHC assigned the descriptive name, “inclusion body disease of cranes” (IBDC) to this disease when reporting the outbreak in the scientific literature, because the disease is characterized by microscopic inclusions in cell nuclei throughout the liver and spleen. Very little is known about how this disease is transmitted. As with duck plague and avian cholera, outbreaks are thought to be initiated by disease carriers within a population of birds. The disease likely spreads by direct contact between infected birds and other susceptible birds and by contact with a virus-contaminated environment. Findings of antibody in sera of cranes bled nearly 3 years before the deaths at ICF indicates that the IBDC virus can be maintained in a captive crane population for at least 2 years and 8 months without causing mortality. The IBDC virus has been isolated from the cloaca of antibody-positive cranes, which indicates the potential for fecal shedding of the virus.

Information and Technology Report↗
USGS1979

Experimental lead poisoning in bald eagles

Captive, crippled bald eagles unsuitable for release were fed lead shot to determine diagnostic criteria for lead poisoning. The eagles were fluoroscoped and bled periodically to determine shot retention and blood delta--aminolevulinic acid dehydratase activity. Microscopic examination revealed renal tubular degeneration, arterial fibrinoid necrosis and myocardial necrosis. Acid-fast intra-nuclear inclusion bodies were not found in proximal convoluted tubule cells. Analyses of blood and toxicological data are not yet complete.

Book chapter↗
USGS2005

Effects of dietary selenium exposure in captive American common eiders

We conducted two studies of Se exposure in captive common eiders (Somateria mollissima). In Study 1, eiders were fed diets with added Se (as L-selenomethionine) in concentrations increasing from 10 ppm to 80 ppm. In Study 2, eiders received control, low exposure (20 ppm Se), and high exposure (60 ppm Se) diets. One duck in the high exposure group in Study 2 died after 36 days. Remaining high exposure ducks in Study 2 and ducks in Study 1 were euthanized after losing 25-30% of their body weight, which occurred after 41 days and 60-78 days, respectively. Body weights did not differ between control and low exposure ducks in Study 2. At the end of Study 1, the mean Se concentration in blood was 32 ppm wet weight (ww). In Study 2, mean blood Se reached 14 ppm ww in the low exposure group and 17 ppm ww in high exposure ducks. Mean Se concentrations in liver were 1252 ppm dry weight (dw) in Study 1, and 351 and 735 ppm dw, respectively, in the low and high exposure groups of Study 2. Oxidative stress was evidenced by Se-associated effects on glutathione metabolism, but not entirely in the same manner as with previous laboratory studies in mallards. In plasma, activities of total and Se-dependent glutathione peroxidase increased with time. As Se concentrations in liver increased, Se-dependent glutathione peroxidase, glutathione reductase, oxidized glutathione, and the ratio of hepatic oxidized to reduced glutathione increased. Total and protein bound sulfhydryl concentrations, reduced glutathione, glutathione-S-transferase, and glucose-6-phosphate dehydrogenase in liver were negatively correlated with Se concentrations in the liver. In Study 2, spleen weights were significantly lower in ducks receiving 60 ppm Se than in those receiving 20 ppm. Gross lesions associated with high Se exposure included emaciation, absence of thymus, loss of nails from digits, and alopecia. Microscopic lesions included severe depletion of lymphoid organs, hepatopathy, and necrosis of feather pulp and feather epithelium. Common eiders fed high levels of Se lost weight and developed lesions similar to findings in experimental mallards, but they accumulated greater Se concentrations in tissues, particularly liver. Field studies have shown that apparently healthy seaducks generally have higher levels of Se in liver than healthy fresh water birds, but lower than the concentrations we found in our study. We conclude common eiders and probably other seaducks have a higher threshold, or adverse effect level, of Se in tissues than fresh water species.

Conference Paper↗
USGS1980

Disseminated visceral coccidiosis in whooping cranes

Three 13- to 18-day-old whooping cranes (Grus americana) and a 9-year-old whooping crane died in outdoor pens at the Patuxent Wildlife Research Center. The deaths were associated with an overwhelming systemic infection by an intracellular protozoan parasite, which resulted in enteritis, granulomatous bronchopneumonia, hepatitis, splenitis, and myocarditis. The clinical, histopathologic, and electron microscopic findings were similar to those in sandhill cranes (Grus canadensis) at the Patuxent Center found to be infected with Eimeria reichenowi and E gruis. Since these eimerian species also parasitize wild whooping cranes, this parasite might be an important pathogenic agent for this species.

Journal of the American Veterinary Medical Associa↗
USGS1979

Disseminated granulomas caused by an unidentified protozoan in sandhill cranes

Oral granulomas were observed in 31 (33%) of 95 captive sandhill cranes (Grus canadensis) at the Patuxent Wildlife Research Center. Necropsy of six of the afflicted cranes revealed granulomatous nodules throughout many of their organ systems. Intracellular protozoan organisms morphologically resembling schizogonic stages were observed within the granulomas by light and electron microscopy. Sexual and asexual stages of coccidia were seen in sections of the intestines of 4 of 5 cranes examined microscopically, and Eimerian oocysts were seen in fecal flotation specimens from 3 of 4 birds.

Journal of the American Veterinary Medical Associa↗
USGS1986

Mortality of captive whooping cranes caused by eastern equine encephalitis virus

Of 39 captive whooping cranes (Grus americana), 7 died during a 7-week period (Sept 17 through Nov 4, 1984) at the Patuxent Wildlife Research Center, Laurel, Md. Before their deaths, 4 cranes did not develop clinical signs, whereas the other 3 cranes were lethargic and ataxic, with high aspartate transaminase, gamma-glutamyl transferase, and lactic acid dehydrogenase activities, and high uric acid concentrations. Necropsies indicated that the birds had ascites, intestinal mucosal discoloration, fat depletion, hepatomegaly, splenomegaly, and visceral gout. Microscopically, extensive necrosis and inflammation were seen in many visceral organs; the CNS was not affected. Eastern equine encephalitis (EEE) virus was isolated from specimens of the livers, kidneys, lungs, brains, and intestines of 4 of the 7 birds that died, and EEE virus-neutralizing antibody was detected in 14 (44%) of the 32 surviving birds. Other infectious or toxic agents were not found. Morbidity or mortality was not detected in 240 sandhill cranes (Grus canadensis) interspersed among the whooping cranes; however, 13 of the 32 sandhill cranes evaluated had EEE virus-neutralizing antibody. Of the 41 wild birds evaluated in the area, 3 (4%) had EEE virus-neutralizing antibody. Immature Culiseta melanura (the most probable mosquito vector) were found in scattered foci 5 km from the research center.

Maryland↗
USGS1994

Erysipelothrix rhusiopathiae infection in a captive bald eagle (Haliaeetus leucocephalus)

An adult bald eagle (Haliaeetus leucocephalus) kept in captivity for nearly 7 yr at the Patuxent Wildlife Research Center, Laurel, Maryland, died suddenly with gross and microscopic lesions characteristic of septicemia. Erysipelothrix rhusiopathiae was isolated from the liver. Fish comprised part of the bird's diet and may have been the source of the organism.

Virginia↗
USGS1982

Inclusion body hepatitis in kestrels (Falco sparverius)

Inclusion body disease of suspected adenovirus etiology was the apparent cause of death of 9 captive kestrels (Falco sparverius). Cloacal hemorrhage was the only prominent gross lesion; disseminated hepatocellular necrosis and intranuclear inclusion bodies were evident microscopically. Attempts to reproduce the disease, and to propagate and serologically characterize the agent were unsuccessful.

Wildlife Disease Association Conference Proceeding↗
USGS2006

Disseminated visceral coccidiosis in a wild white-naped crane (Grus vipio)

Disseminated visceral coccidiosis (DVC) was unexpectedly recognized in a wild white-naped crane (Grits vipio) killed by phosphamidon insecticide. On gross pathologic examination, widely disseminated white nodules were found on the serosa of the proventriculus, gizzard, and intestine, as well as on the surface and in the parenchyma of liver, spleen, and cardiac muscle. Microscopically, asexual stages of a coccidia were observed in some nodules. However, the species of coccidia could not be determined because no oocysts were found on fecal examination. This is believed to be the first reported case of DVC in a wild white-naped crane infected with Eimeria spp.

Journal of Wildlife Diseases↗
USGS2010

Elodontoma in captive southern red-backed voles ( Myodes gapperi )

Five southern red-backed voles ( Myodes gapperi ) of the first generation of a wild-caught breeding colony were presented with lesions at the maxillary incisors consistent with elodontoma. The affected animals had a history of chronic weight loss, were >16 months of age, and were siblings. Radiographs of the head showed multiglobular to irregularly outlined mineral opacity masses at the apices of the maxillary incisors. On necropsy, maxillary incisor teeth were not grossly visible, and a gingival ulceration was observed at the expected site of eruption. Microscopically, the apical region of the maxillary incisors was thickened or replaced by irregular dental tissue masses consistent with elodontoma. This is the first report to describe elodontoma in red-backed voles.

Journal of Zoo and Wildlife Medicine↗
USGS2011

Measured reflectance suppressed by thin-film interference of crude oil smeared on glass - as on vitrinite in coal or petroliferous rocks

The tool of measuring "vitrinite reflectance" under a microscope has great value in petroleum exploration and coal utilization, and the reflectance is a simple number, such as 1.4% Ro, with some slight variations depending on technique. Sample collection, preparation and measurement are simple and many sedimentary rocks yield vitrinite. However, the reported number can lead one astray if its origin and quality are not fully understood. I analyze here just one factor, "smear" of crude oil on the polished surface (from the sample), which may reduce reflectance because of thin-film interference. Some other causes of error are listed in an addendum to this note.

Society for Organic Petrology Newsletter↗
USGS2008

Trichinella murrelli in scavenging mammals from south-central Wisconsin, USA

Tissues and serum from 59 raccoons (Procyon lotor), 42 coyotes (Canis latrans), and seven Striped Skunks (Mephitis mephitis) collected in Dane and Iowa Counties, Wisconsin, USA, between October 2005 and March 2006 were microscopically and serologically examined for the presence of Trichinella spp. Encapsulated larvae were found on compression slides prepared from tongue tissues from a few animals. Complete tissue digestion of tongues revealed that 19% of the raccoons, 26% of the coyotes, and none of the seven skunks tested were infected with Trichinella spp. Cats were subsequently experimentally infected by feeding them the raccoon tissues containing muscle larvae, and muscle larvae isolated from the collected tongues were experimentally transmitted to mice. Multiplex polymerase chain reaction analysis of the isolated muscle larvae demonstrated two distinct bands migrating at 127 base pairs (bp) and 316 bp in all samples, which together are diagnostic for Trichinella murrelli; the isolates were assigned Istituto Superiore di Sanita (ISS) codes ISS1656 through ISS1667, and ISS1708 through ISS1710 by the International Trichinella Reference Centre. These findings extend the geographic range of T. murrelli into Wisconsin, USA. ?? Wildlife Disease Association 2008.

Journal of Wildlife Diseases↗
USGS1984

ORIGIN OF QUARTZ IN COAL.

Both a scanning electron microscope and an electron microprobe (EMP) were used in this study to analyze the cathodoluminescence properties of quartz grains in samples of the Upper Freeport coal bed because quartz grains in coal are small (silt sized) and below the resolution capabilities of a standard luminoscope. Quartz grains were identified by the detection of silicon alone with energy dispersive X-ray units attached to both the SEM and the EMP.

Conference Paper↗
USGS1985

GEOLOGIC ASPECTS OF TIGHT GAS RESERVOIRS IN THE ROCKY MOUNTAIN REGION.

The authors describe some geologic characteristics of tight gas reservoirs in the Rocky Mountain region. These reservoirs usually have an in-situ permeability to gas of 0. 1 md or less and can be classified into four general geologic and engineering categories: (1) marginal marine blanket, (2) lenticular, (3) chalk, and (4) marine blanket shallow. Microscopic study of pore/permeability relationships indicates the existence of two varieties of tight reservoirs. One variety is tight because of the fine grain size of the rock. The second variety is tight because the rock is relatively tightly cemented and the pores are poorly connected by small pore throats and capillaries.

JPT, Journal of Petroleum Technology↗
USGS1985

Elemental X-ray mapping of agglutinated foraminifer tests: A non- destructive technique for determining compositional characteristics.

The composition of agglutinated foraminiferal tests vary remarkably in response to local substrate characteristics, physiochemical properties of the water column and species- dependant selectivity of test components. We have employed a technique that combines a scanning electron microscope with an energy dispersive X-ray spectrometer system to identify major and minor elemental constituents of agglutinated foraminiferal walls. As a sample is bombarded with a beam of high energy electrons, X-rays are generated that are characteristic of the elements present. As a result, X- ray density maps can be produced for each of several elements present in the tests of agglutinated foraminifers.

Micropaleontology↗