Biomedical subjects

John H Tegzes

Publications and source records attributed to John H Tegzes.

5 recordsLinked to original sources

PubMed2004

Influence of age, sex, and production class on liver zinc concentration in calves.

Determination of zinc concentrations in the liver of calves and young stock is commonly requested by practitioners and nutritionists to assess whether they receive an appropriate amount of zinc in their diet. However, interpretation of liver zinc concentrations is currently based on information reported for adult cattle for which the health status was unknown and irrespective of production class, sex, and age. A retrospective study of necropsy reports was undertaken to assess the relationships between liver zinc concentrations and age, sex, and production class for calves that did not have a history compatible with zinc toxicosis or zinc deficiency. Results of a generalized least squares, polynomial regression analysis of 474 records found that zinc concentration was not affected by sex (P = 0.29) or production class (P = 0.50). Zinc concentration was significantly associated with linear (P < 0.00001) and nonlinear (quadratic, P = 0.0039) functions of age (r2 = 0.1503), where the concentration decreased from 93 mg/kg wet weight at 30 days of age to 57 mg/kg wet weight at 9 months of age, after which it began to increase. The age-specific 95% confidence limits of the mean concentration for a group of calves and the 95% prediction limits of a single concentration value for an individual animal estimated in this study suggest reconsideration of the recommended limits for liver zinc concentration in calves. As a consequence of the significant influence of age on liver zinc concentration of calves presumably not experiencing zinc toxicosis or deficiency, diagnosis of zinc imbalances based on liver zinc concentration needs to consider age as a diagnostic covariate.

Age Factors↗

PubMed2003

Cyanide toxicosis in goats after ingestion of California Holly (Heteromeles arbutifolia).

Cyanogenic glycosides are found in many native and naturalized plants throughout North America. The glycosides themselves are not toxic, but they yield hydrogen cyanide (hydrocyanic or prussic acid) when they are hydrolyzed by beta-glycosidases, either as a result of injury to the plant cells or by microbial action in the rumen. Hydrogen cyanide is readily absorbed from the gastrointestinal tract. Cyanide ion binds with iron in cytochrome oxidase, interfering with cellular respiration. The clinical effects are peracute, often resulting in death less than 1 hour after ingestion. This study describes a case that resulted in significant morbidity and mortality in a herd of goats after exposure to California holly (Heteromeles arbutifolia).

Animals↗

PubMed2002

Toxic mushrooms.

Poisonous mushrooms contain toxins that are as diverse as the mushrooms themselves. Clinical syndromes often involve multiple organ systems, and progression of clinical signs is often directly related to the quantity eaten. Diagnostic detection of the toxins is rarely an option; rather, diagnosis is based on a history of possible exposure and identification of mushroom species in the stomach contents and environment. Treatments are usually based on clinical signs, as most mushroom toxins are without an antidote. There are exceptions, however, and prompt identification of mushroom species involved is vital whenever possible. Collection of the toxicologic minimum database and gastrointestinal decontamination are important in all cases where mushroom ingestion is suspected.

Agaricales↗

PubMed2002

Coma and apnea in a dog with hydroxyzine toxicosis.

Hydroxyzine is a commonly prescribed H1-receptor antagonist in small animal practice. The most common adverse effect reported after therapeutic dosing is mild sedation; severe reactions resulting in coma have occasionally been reported in children. We present a case of large po hydroxyzine exposure causing in coma and apnea in a dog. Exposure was confirmed with gas chromatography/mass spectrometry analysis of urine. Extensive therapeutic measures to enhance drug elimination and assist ventilation were required for 11 d. The positive outcome justifies critical care of similarly exposed animals. Veterinarians should be aware of the potential for coma and apnea secondary to hydroxyzine exposure.

Animals↗

PubMed2002

Amanita mushroom poisoning: efficacy of aggressive treatment of two dogs.

Amatoxins, the primary toxins found in mushrooms of the genus Amanita, are very toxic to dogs. Acute fulminant liver failure and death can occur within a few days of ingestion. By their curious nature, dogs, especially young dogs, are prone to ingest mushrooms. Early identification of suspect mushrooms, and prompt emergency measures aimed at decreasing absorption of the toxins can improve the chance of survival. Knowing the major clinical syndromes associated with Amanita mushroom toxicosis can help direct the treatment and supportive care of affected animals and improve survival rates. We describe 2 cases in dogs with confirmed ingestion of Amanita phalloides and Amanita ocreata resulting in fulminant liver failure. Death occurred in 1 dog despite aggressive treatment measures including hemoperfusion, while aggressive measures resulted in a favorable outcome in the other dog.

Amanita↗