PubMed Health⌕ Search

Biomedical subjects

H S Gosser

Publications and source records attributed to H S Gosser.

At least 19 recordsLinked to original sources
PubMed1998

District, state or regional veterinary diagnostic laboratories.

The district, regional or state laboratory is the local laboratory to which veterinarian practitioners usually submit samples, and consequently these laboratories are usually the first to observe a suspected disease problem. In most countries, these laboratories are under the jurisdiction of the State or region in which they are located. In the United States of America (USA), most veterinary diagnostic laboratories are State-associated and operate under the aegis of either the State Department of Agriculture or a university. The national laboratory provides reference assistance to the State laboratories. In the USA, the national Laboratory (the National Veterinary Services Laboratories) acts as a consultant to confirm difficult diagnoses and administer performance tests for State-associated laboratories. District, state or regional laboratories need to share information regarding technological advances in diagnostic procedures. This need was met in the USA by the formation of the American Association of Veterinary Laboratory Diagnosticians (AAVLD) in the late 1950s. Another requirement of district, state or regional diagnostic laboratories is a method to confirm quality assurance, which was fulfilled in the USA by an accreditation programme established through the AAVLD. The Accreditation Committee evaluates laboratories (on request) in terms of organisation, personnel, physical facilities and equipment, records, finance and budget. Those laboratories which meet the standards as established in the 'Essential Requirements for Accreditation' are given accreditation status, which indicates that they have the expertise and facilities to perform tests on food-producing animals for shipment in national or international commerce and on companion, laboratory or zoo animals. While confidentiality of test records is most important, it is becoming necessary to release certain types of animal disease test information if a country is to participate in the exportation of animals and animal products. As district, state and regional laboratories operate under many different administrative entities (i.e., universities, State governments and the Federal government), various checks at different administrative levels provide safeguards and reduce the possibility of faulty disease reporting.

Accreditation↗
PubMed1995

An epizootic of hemorrhagic disease in white-tailed deer (Odocoileus virginianus) in Missouri: necropsy findings and population impact.

An epizootic occurred among white-tailed deer (Odocoileus virginianus) from July through October 1988 in Missouri (USA). From late July through September, nine necropsied deer had lesions of the peracute or acute forms of hemorrhagic disease (HD) or no apparent lesions, whereas two deer necropsied in October had lesions of the chronic form of HD. Epizootic hemorrhagic disease virus was isolated from two necropsied deer. Based on changes in population indices, there is evidence that deer populations declined in seven of Missouri's 57 deer management units from 1987 to 1990. Based on a deterministic model designed to simulate deer populations in management units, it appeared that summer and fall 1988 mortality ranging from 6% to 16% accounted for the population decreases in deer management units with population declines. Heavily hunted areas where high deer mortality was not reported in the summer and fall of 1988 did not have population declines. Based on these results, we believe that HD mortality was high and resulted in deer population declines in parts of Missouri when combined with hunting harvest.

Animals↗
PubMed1994

Amaranthus retroflexus (redroot pigweed) poisoning in cattle.

Amaranthus retroflexus (redroot pigweed)-induced nephrotoxicity was diagnosed in 6 herds of cattle from 3 counties in southwest Missouri. Forty-eight cows and calves died and another 35 were clinically affected. Serum urea nitrogen concentration, determined in 4 affected calves, was between 55 and 284 mg/dl, and serum creatinine concentration was between 6.7 and 29.9 mg/dl. Postmortem examination of affected cows and calves revealed amber-colored fluid in peritoneal cavities and retroperitoneal perirenal edema. Histologic examination of kidney sections revealed widespread degeneration and necrosis of proximal and distal tubules. Compared with archived kidney sections from cattle with Quercus (oak) poisoning, distal renal tubules were more severely affected. Oak poisoning also was associated with a higher prevalence of interstitial fibrosis and renal tubular oxalosis. We concluded that ingestion of the aerial and leafy portions of pigweed by cattle in drought situations does not necessarily lead to nitrate-induced sudden death associated with consumption of the nitrate-containing stems.

Animals↗
PubMed1993

Aldrin intoxication and clearance of associated dieldrin residues in a group of feedlot cattle.

A sudden onset of bizarre neurologic dysfunction was found in 8 of 90 mixed-breed feeder calves. Seven other calves were dead, and 3 more died during the next week. A diagnosis of organochlorine toxicosis was made when rumen and abomasal contents from 1 of the calves revealed 22.4 and 20.6 micrograms of aldrin/g of ingesta, respectively. Complete feeds retrieved from self-feeders contained 54 and 528 micrograms of aldrin/g of feed. The initial concentration range in fat from 40 live calves was 6.01 to 42.44 micrograms of dieldrin/g of fat. Additional fat samples were analyzed to verify residue compliance until the entire herd was clear of residue 18 months after removal of the contaminated ration. The range of apparent half-lives for dieldrin in body fat of heifers and steers was 69 to 231 and 53 to 116 days, respectively. These findings demonstrate the considerable variability in apparent half-life of dieldrin in field cases. In cases of dieldrin-contaminated livestock, veterinarians and regulatory personnel must accurately determine the necessary slaughter withholding times so that informed economic decisions are made in the best interest of the producer while enhancing the probability of a safe food supply. Excretion rates of dieldrin from field-contaminated cattle may not be consistent with results obtained under experimental conditions.

Adipose Tissue↗
PubMed1991

Cutaneous neoplasia in 340 cats.

A total of 340 cases of cutaneous neoplasia were diagnosed in 340 of 3,564 cats that were examined by biopsy or necropsy during a 41-month period from January 1, 1986 through May 31, 1989. Eighteen types of tumor occurred, but four types comprised 77% of the cases. These were basal cell tumor, 89 cases (26%, mean age 10.3); mast cell tumor, 72 cases (21%, mean age 8.6); squamous cell carcinoma, 52 cases (15%, mean age 11.6); and fibrosarcoma, 50 cases (15%, mean age 10.2). For each of these four types of tumors, peak number of cases occurred in cats older than 10 years. Mast cell tumor was the only tumor diagnosed in cats younger than 1 year. The head was the most common site for basal cell tumors, mast cell tumors, and squamous cell carcinomas. The legs were the most common location of fibrosarcomas. Siamese cats had approximately three times as many mast cell tumors as statistically expected, but only one-fourth as many squamous cell carcinomas. Breed predilection for other skin tumors was not apparent. Sex predilection was not detected for any skin tumor.

Animals↗
PubMed1990

Chlamydial infection in aborted and stillborn lambs.

Chlamydia psittaci is a major cause of ovine abortion in the fourth to fifth months of gestation. During the lambing seasons of 1986, 1987, and 1988, fetuses from 52 cases of ovine abortion, stillbirth, or perinatal death were submitted to the laboratory for necropsy examination. Placenta or fetal tissues from 34 cases were cultured on mouse L cells for C. psittaci. Chlamydia psittaci was identified by immunofluorescence on cultures in 20 of these cases. The major gross lesion consistently associated with chlamydial abortion was placentitis with multifocal cotyledonary necrosis and accumulation of red-brown exudate in the intercotyledonary placenta. Chlamydiae appeared as spherical organisms, less than 1 micron in diameter, in the cytoplasm of trophoblasts in impression smears of cotyledons. Histologically, placentitis was sometimes accompanied by pneumonia or encephalitis in the fetus. Chlamydia psittaci was considered the cause for fetal death when chlamydial isolation was associated with placentitis or inflammation of other fetal tissues and when other abortifacient agents were not detected.

Abortion, Veterinary↗
PubMed1986

Transmissibility and abortogenic effect of equine viral arteritis in mares.

A group of 14 pregnant mares was exposed via contact to 4 mares bred to stallions infected with equine viral arteritis virus. There was a demonstrable febrile response in each donor mare and in 12 of the pregnant mares. All 18 mares became seropositive after exposure. Equine viral arteritis virus was isolated from the nasopharynx of 5 pregnant mares, but not from the donor mares. Ten of the pregnant mares aborted, and virus was isolated from fetal specimens or placenta of 8.

Abortion, Veterinary↗
PubMed1986

Cassia occidentalis toxicosis in growing pigs.

Approximately 70 feeder pigs developed ataxia and other signs of neuromuscular dysfunction. The ration fed the pigs was found to be contaminated with Cassia occidentalis seeds. Experimentally, other feeder pigs were fed this ration, and they developed ataxia and other signs of neuromuscular dysfunction within 6 to 8 weeks. In further experiments, feeder pigs fed diets containing 1%, 2%, or 4% ground cassia seeds also became intoxicated. Microscopically, diaphragmatic myopathy and pancreatic tissue necrosis were the principal pathologic findings.

Animal Feed↗
PubMed1984

Aflatoxicosis in feeder cattle.

Aflatoxicosis was diagnosed as the cause of deaths in a group of crossbred feeder steers. Corn used in the ration being fed the steers was found to be contaminated with 1,500 ng of aflatoxin/g. Residues of the mycotoxin were detected in kidney tissue, and microscopic examination of liver sections revealed lesions typical of aflatoxicosis.

Animal Feed↗
PubMed1983

Cyclopiazonic acid production by Aspergillus flavus and its effects on broiler chickens.

Cyclopiazonic acid (CPA) was purified from cultures of Aspergillus flavus, and ca. 14 g of the toxin was collected for use in feeding studies. Chicken rations were artificially contaminated with purified CPA at concentrations of 10, 50, and 100 ppm (microgram/g) and fed ad libitum to eight groups of chickens for 7 weeks. Chickens receiving feed with 100 ppm of CPA had high mortality, decreased weight gain, and poor feed conversion when compared with birds receiving other doses. Postmortem examination showed that chickens fed the two greatest doses of CPA had proventricular lesions characterized by mucosal erosion and hyperemia (100 ppm) and by thick mucosa and dilated proventricular lumens (50 ppm). Birds given 100 ppm of CPA in feed also had numerous yellow foci in their livers and spleens. Microscopic examination of tissues of birds that received 100 ppm of CPA revealed ulcerative proventriculitis, mucosal necrosis in the gizzard, and hepatic and splenic necrosis and inflammation. Birds given 50 ppm of CPA had hyperplasia of the proventricular mucosal epithelium. Birds given 10 ppm of CPA and control birds had no significant treatment-related lesions.

Animal Feed↗
PubMed1983

Paralysis in swine due to focal symmetrical poliomalacia: possible selenium toxicosis.

A paralytic disease in swine was observed on three farms located in the same geographical area of Georgia. Postmortem examinations revealed the paralysis to be related to spinal poliomalacia. Feed collected from two of the affected farms was used in a feeding study, and the paralytic condition was reproduced. In pigs from both the feeding trial and field cases, the poliomyelomalacia was characterized by focal, symmetrical lesions located in the cervical and lumbar intumescences. Selenium was detected in the feed at levels ranging from 19 to 24 ppm.

Animal Feed↗
PubMed1982

Coccidiosis in swine: dose and age response to Isospora suis.

Coccidiosis is a disease of the young piglet due to infection with Isospora suis and is characterized by diarrhea which is nonresponsive to antibacterial therapy. There is variable morbidity and mortality. Piglets develop a more severe clinical illness and enteritis when infected with I. suis at one to three days of age than when infected at two weeks of age. Microscopic lesions range from villous atrophy and mild erosion to severe fibrinonecrotic enteritis.

Age Factors↗
PubMed1982

Demonstration of immunity against Isospora suis in swine.

Piglets naturally exposed or experimentally infected with Isospora suis oocysts were given challenge doses of oocysts to determine the extent of development of immune resistance. Piglets in both studies shed low numbers of, or no detectable oocysts, following challenge. Administration of methylprednisolone acetate failed to induce oocyst shedding in previously infected piglets. Piglets rechallenged with I. suis following steroid injections also failed to shed significant numbers of oocysts suggesting development of immunity to reinfection.

Age Factors↗
PubMed1981

Cocklebur (Xanthium strumarium, L. var. strumarium) intoxication in swine: review and redefinition of the toxic principle.

Cocklebur (Xanthium strumarium) fed to feeder pigs was associated with acute to subacute hepatotoxicosis. Cotyledonary seedings fed at 0.75% to 3% of body weight or ground bur fed at 20% to 30% of the ration caused acute depression, convulsions, and death. Principle gross lesions were marked serofibrinous ascites, edema of the gallbladder wall, and lobular accentuation of the liver. Acute to subacute centrilobular hepatic necrosis was present microscopically. The previously reported toxic principle, hydroquinone, was not recovered from the plant or bur of X. strumarium. Authentic hydroquinone administered orally failed to produce lesions typical of cocklebur intoxication but did produce marked hyperglycemia. Carboxyatractyloside recovered from the aqueous extract of X. strumarium and authentic carboxyatractyloside, when fed to pigs, caused signs and lesions typical of cocklebur intoxication. Marked hypoglycemia and elevated serum glutamic oxaloacetic transaminase and serum isocitric dehydrogenase concentrations occurred in pigs with acute hepatic necrosis that had received either cocklebur seedlings, ground bur or carboxyatractyloside.

Animals↗
PubMed1981

Occurrence of antibody to Trypanosoma cruzi in dogs in the southeastern United States.

Seven of 365 dogs from Georgia and other southeastern states were seropositive for antibody to Trypanosoma cruzi by the complement-fixation (CF) test. Sera from 24 dogs, including the 7 dogs seropositive by CF test, were reactive at dilutions of 1:128 or 1:256 by the direct-agglutination (DA) test. Dogs with positive CF titers were significantly (P less than 0.05) younger than were the dogs in the total population surveyed. The occurrence of antibody to T cruzi was similar, regardless of the dogs' origin, sex, or length of hair. Dogs with specific antibody to T cruzi did not have clinical signs of disease related to the cardiovascular or gastrointestinal systems, the systems most frequently affected in American trypanosomiasis (Chagas' disease). Sera from an additional 20 dogs from Minnesota were examined by the DA test. One of these sera had a reaction at a dilution of 1:2, and 19 sera had no reaction in the DA test for antibody to T cruzi.

Animals↗