D W Hamar

Colorado State University, Fort Collins, Colorado, United States

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Publications (38)66.09 Total impact

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    ABSTRACT: To determine the safety and efficacy of high-dose fomepizole compared with ethanol (EtOH) in cats with ethylene glycol (EG) toxicosis. Prospective study. University veterinary research laboratory. Thirteen cats. Two cats received injections of high-dose fomepizole (Study 1). Three cats received lethal doses of EG and fomepizole treatment was initiated 1, 2, or 3 hours later (Study 2). Eight cats received a lethal dose of EG and were treated with fomepizole or EtOH (Study 3). Cats treated with fomepizole received 125 mg/kg IV initially, then 31.25 mg/kg at 12, 24, and 36 hours. Cats treated with EtOH received 5 mL of 20% EtOH/kg IV initially, then every 6 hours for 5 treatments, then every 8 hours for 4 treatments. Cats also received fluids and supportive therapy as needed. Clinical signs were monitored and serial blood analyses performed. Cats receiving fomepizole experienced mild sedation but no biochemical evidence of toxicity. Cats receiving fomepizole for EG intoxication survived if therapy was initiated within 3 hours of EG ingestion. One of the 6 developed acute renal failure (ARF) but survived. Only 1 of the 3 cats treated with EtOH 3 hours following EG ingestion survived; 2 developed ARF and were euthanized. Cats treated 4 hours following EG ingestion developed ARF, whether treated with EtOH or fomepizole. Fomepizole is safe when administered to cats in high doses, prevents EG-induced fatal ARF when therapy is instituted within 3 hours of EG ingestion, and is more effective than treatment with EtOH.
    Journal of veterinary emergency and critical care (San Antonio, Tex. : 2001). 04/2010; 20(2):191-206.
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    ABSTRACT: To assess heritability and mode of inheritance for hereditary equine regional dermal asthenia (HERDA) in Quarter Horses. 1,295 horses with Quarter Horse bloodlines, including 58 horses affected with HERDA. Horses were classified as affected or unaffected or as undetermined when data were insufficient to assess phenotype. Pedigree data were analyzed to determine the probable mode of inheritance. Heritability was estimated by use of Bayesian statistical methods. Heritability (mean+/-SD) of HERDA was estimated to be 0.38+/-0.13, with both sexes having an equal probability of being affected. Results for evaluation of the pedigrees were consistent with a single Mendelian autosomal recessive mode of inheritance. HERDA in Quarter Horses is an inherited disease, and affected horses are more likely to produce affected offspring. An autosomal recessive mode of inheritance should be considered by people making breeding decisions involving Quarter Horses when a first-degree relative has been confirmed with HERDA or has produced affected offspring. In addition, breeders whose horses have produced affected offspring can reduce the likelihood of producing affected horses in the future by avoiding inbreeding.
    American Journal of Veterinary Research 04/2005; 66(3):437-42. · 1.21 Impact Factor
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    ABSTRACT: Data on fifty horses with hereditary equine regional dermal asthenia (HERDA; "hyperelastosis cutis") were collected on clinical, histopathological, ultrastructural and immunohistological findings. All horses were Quarter horses or of Quarter horse ancestry. Pedigree evaluation strongly supported an autosomal recessive mode of inheritance. The most common lesions were seromas/haematomas, open wounds, sloughing skin, and loose, easily tented skin that did not return to its initial position. Definitive diagnosis could not be made via histopathology, although the presence of tightly grouped thin and shortened collagen fibres arranged in clusters in the deep dermis was suggestive of the disease. Trichrome, acid orcein-Giemsa and immunohistochemical stains for collagens I and III showed no consistent abnormalities compared to control horses; an increase in elastic fibres was not a consistent finding. Electron microscopy showed no abnormalities in the periodicity of the collagen bundles; neither orientation nor variation of cross-section diameter of the collagen fibrils differentiated control from affected horses. The diagnosis of HERDA relies on clinical presentation, but may be supported by suggestive (although not pathognomonic) histopathological lesions.
    Veterinary Dermatology 09/2004; 15(4):207-17. · 1.99 Impact Factor
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    ABSTRACT: To analyze the sulfur content of water and forage samples from a geographically diverse sample of beef cow-calf operations in the United States and to estimate frequency and distribution of premises where forage and water resources could result in consumption of hazardous amounts of sulfur by cattle. Cross-sectional study. 709 forage samples from 678 beef cow-calf operations and individual water samples from 498 operations in 23 states. Sulfur content of forage samples and sulfate concentration of water samples were measured. Total sulfur intake was estimated for pairs of forage and water samples. Total sulfur intake was estimated for 454 pairs of forage and water samples. In general, highest forage sulfur contents did not coincide with highest water sulfate concentrations. Overall, 52 of the 454 (11.5%) sample pairs were estimated to yield total sulfur intake (as a percentage of dry matter) > or = 0.4%, assuming water intake during conditions of high ambient temperature. Most of these premises were in north-central (n = 19) or western (19) states. Results suggest that on numerous beef cow-calf operations throughout the United States, consumption of forage and water could result in excessively high sulfur intake. All water sources and dietary components should be evaluated when assessing total sulfur intake. Knowledge of total sulfur intake may be useful in reducing the risk of sulfur-associated health and performance problems in beef cattle.
    Journal of the American Veterinary Medical Association 10/2002; 221(5):673-7. · 1.67 Impact Factor
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    ABSTRACT: Concentrations of iron, copper, and zinc were measured in livers of 95 dogs that were suspected of having liver disease. Iron concentrations ranged from 177 to 7,680 ppm (dry weight basis); 54 dogs had iron concentrations greater than the normal concentration of 1,200 ppm. Iron stores were present in Kupffer cells and macrophages but not hepatocytes. The dogs did not have lesions of hemochromatosis. Dogs with high liver iron tended to have high liver copper and inflammatory lesions. High liver copper concentrations usually were associated with hepatocellular necrosis and fibrosis. High liver zinc was found in only 5 animals and was accompanied by histologic inflammatory lesions in one. In humans, increased iron concentration in the liver exacerbates liver damage caused by a variety of insults, and the same may be true for dogs.
    Journal of veterinary diagnostic investigation: official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc 10/2002; 14(5):396-402. · 1.23 Impact Factor
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    ABSTRACT: We compared serum concentrations of zinc, chromium, and iron in dogs with cancer to those of normal dogs. Dogs with lymphoma (n = 50) and osteosarcoma (n = 52) were evaluated. Dogs with lymphoma had significantly lower (P= .0028) mean serum zinc concentrations (mean ± SD; 1.0 ± 0.3 mg/L) when compared to normal dogs (1.2 ± 0.4 mg/L). Dogs with osteosarcoma also had lower mean serum zinc concentrations (1.1 ± 0.4 mg/L), but this difference was not significant (P= .075). Serum chromium concentrations were significantly lower in dogs with lymphoma (2.6 ± 2.6 μg/L, P= .0007) and osteosarcoma (2.4 ± 3.1 μg/L, P= .0001) compared to normal dogs (4.7 ± 2.8 μg/L). Serum iron concentrations and total iron-binding capacity were significantly lower in dogs with lymphoma (110.8 ± 56.7 μg/dL, P < .0001, and 236.6 ± 45.6 μg/dL, P < .0001, respectively) and osteosarcoma (99.6 ± 49.3 μg/dL, P < .0001, and 245.0 ± 43.8 μg/dL, P= .0011, respectively) when compared to normal dogs (175.1 ± 56.7 μg/dL and 277.1 ± 47.4 μg/dL). Mean ferritin concentration was significantly higher in dogs with lymphoma (1291.7 ± 63.0 μg/L) than in normal dogs (805.8 ± 291.1 μg/L, P < .0001) and dogs with osteosarcoma (826.5 ± 309.2 μg/L, P < .0001). Further investigation is needed to explore the clinical significance of these mineral abnormalities in dogs with cancer.
    Journal of Veterinary Internal Medicine 10/2001; 15(6):585 - 588. · 2.06 Impact Factor
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    ABSTRACT: A feline model of Niemann-Pick disease type C (NPC) was employed to evaluate the effect of dietary cholesterol restriction on progression of disease. Two NPC-affected treated cats were fed a cholesterol-restricted diet beginning at 8 weeks of age; the cats remained on the diet for 150 and 270 days respectively. The study goal was to lower the amount of low density lipoprotein (LDL) available to cells, hypothetically reducing subsequent lysosomal accumulation of unesterified cholesterol and other lipids. Neurological progression of disease was not altered and dietary cholesterol restriction did not significantly decrease storage in NPC-affected treated cats. One NPC-affected treated cat had decreased serum alkaline phosphatase activity (ALP) and decreased serum cholesterol concentration. Liver lipid concentrations of unesterified cholesterol, cholesterol ester and phospholipids in NPC-affected treated cats were similar to those seen in NPC-affected untreated cats. Ganglioside concentrations in the NPC-affected treated cats and NPC-affected untreated cats were similar. Histological findings in liver sections from NPC-affected treated cats showed a diffuse uniform microvacuolar pattern within hepatocytes and Kupffer cells, in contrast to a heterogeneous macro/microvacuolar pattern and prominent nodular fibrosis in NPC-affected untreated cats. Similar differences in vacuolar patterns were seen in splenic macrophages. Although some hepatic parameters were modified, dietary cholesterol restriction did not appear to alter disease progression in NPC-affected kittens.
    Journal of Inherited Metabolic Disease 09/2001; 24(4):427-36. · 4.14 Impact Factor
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    ABSTRACT: To determine and compare substrate specificity and kinetic rate constants of feline and canine alcohol dehydrogenase (ADH) with ethanol (EtOH) and ethylene glycol (EG) as substrates in vitro, with and without fomepizole. Livers from 3 dogs and 3 cats. Canine and feline ADH activity, in cytosolic fractions of homogenized liver, was determined by use of various concentrations of nicotinamide adenine dinucleotide (NAD), EtOH, or EG as substrates. Initial reaction velocities were calculated, and kinetic inhibition rate constants (Ki) for fomepizole were determined. Substrate specificity of canine and feline ADH for EtOH or EG was not significantly different. A 2-fold difference was detected in the maximal velocity of canine, compared with feline, ADH, using either substrate. Fomepizole Ki in feline hepatic homogenates was significantly greater than Ki in canine hepatic homogenates when either EtOH or EG was used as substrate (10- and 30-fold, respectively). A 6-fold increase in the concentration of fomepizole was required to achieve ADH inhibition, with feline homogenates equivalent to those of canine homogenates. Feline ADH has lower enzymatic capacity for turnover or is less concentrated in liver than canine ADH with regard to EtOH and EG catalysis. Canine ADH was more effectively inhibited by fomepizole than feline ADH. Results suggest that higher dosages of fomepizole may be more effective to treat cats with EG intoxication than dosages reported to treat dogs.
    American Journal of Veterinary Research 05/2000; 61(4):450-5. · 1.21 Impact Factor
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    ABSTRACT: To determine effects of dietary cysteine on blood sulfur amino acids (SAA), reduced glutathione (GSH), oxidized glutathione (GSSG), and malondialdehyde (MDA) concentrations in cats. 12 healthy adult cats. Cats were fed diets with a nominal (0.50 g/100 g dry matter [DM]), moderate (1.00 g/100 g DM), or high (1.50 g/100 g DM) cysteine content in a 3 X 3 Latin square design with blocks of 8 weeks' duration. Venous blood samples were collected after each diet had been fed for 4 and 8 weeks, and a CBC and serum biochemical analyses were performed; poikilocyte, reticulocyte, and Heinz body counts were determined; and MDA, GSH, GSSG, and SAA concentrations were measured. Blood cysteine and MDA concentrations were not significantly affected by dietary cysteine content. Blood methionine, homocysteine, and GSSG concentrations were significantly increased when cats consumed the high cysteine content diet but not when they consumed the moderate cysteine content diet, compared with concentrations obtained when cats consumed the nominal cysteine content diet. Blood GSH concentrations were significantly increased when cats consumed the moderate or high cysteine content diet. Increased dietary cysteine content promotes higher blood methionine, homocysteine, GSH, and GSSG concentrations in healthy cats. Supplemental dietary cysteine may be indicated to promote glutathione synthesis and ameliorate adverse effects of oxidative damage induced by disease or drugs.
    American Journal of Veterinary Research 04/1999; 60(3):328-33. · 1.21 Impact Factor
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    ABSTRACT: During a 2-week period, 16 of 150 recently weaned calves developed signs of polioencephalomalacia (PEM). One calf was examined and treated at our veterinary teaching hospital and a necropsy was performed on a calf that died. During the peak of the outbreak, clinicians visited the ranch. Ruminal hydrogen sulfide (H2S) and blood thiamine concentrations were measured in 10 clinically normal penmates of PEM-affected calves. Ruminal H2S concentrations were high (> 0.695 mg/L [> 500 ppm]) in all cattle (mean, 12.19 mg/L [8,770 ppm]). All blood thiamine values were within the reference range. Within 12 hours after measurement of blood thiamine concentrations, 2 of the calves from which samples were obtained developed clinical signs of PEM. Dietary analysis revealed an estimated sulfur intake of 0.9% per calf on a dry-matter basis. Hay contributed most of this sulfur. In the investigation reported here, an outbreak of PEM was associated with high ruminal H2S concentrations and excess sulfur intake without evidence of thiamine deficiency.
    Journal of the American Veterinary Medical Association 01/1999; 213(11):1599-604, 1571. · 1.67 Impact Factor
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    ABSTRACT: Weight gain is a common problem in domestic cats, but little is known about its metabolic effects. The purpose of this study was to determine the effects of diet-induced weight gain and subsequent weight loss on metabolic rate, body composition, and glucose tolerance. Gain of approximately 20 per cent body weight (divided approximately equally between fat and fat-free mass) over three months resulted in insulin resistance in females, indicated by increases in basal insulin concentration (68.2+/-7.9 to 119+/-16.5 pmol litre(-1), P<0.05), insulin peak response to glucose (241.1+/-31.6 to 315.0+/-23.0 pmol litre(-1), P<0.05), and deltaI/deltaG (14.2+/-2.6 to 18.1+/-1.3 pmol mmol(-1), P<0.05) compared with pre-gain values. The same numerical trend was noted in male cats, however, changes were not significant (P>0.05). Alterations in serum lipids included significant (P<0.05) elevations in triglyceride concentrations in male cats and decreased beta-lipoprotein concentrations in both genders. Weight loss over three months normalised basal insulin, insulin response to glucose, and serum triglyceride concentrations, and resulted in significant (P<0.05) decreases in serum concentrations of beta- and prebeta-lipoproteins, cholesterol, and triiodothyronine. Diet-induced weight gain of three months' duration, followed by three months' maintenance of increased body weight did not affect fasting or resting metabolic rate. Development and severity of impaired glucose tolerance, insulin resistance, and other changes may be affected by duration and possibly severity of weight gain.
    Research in Veterinary Science 01/1998; 64(1):11-6. · 1.51 Impact Factor
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    Journal of veterinary diagnostic investigation: official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc 11/1997; 9(4):441-3. · 1.23 Impact Factor
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    ABSTRACT: Transient echinocytosis has been reported in association with snake envenomation in humans and dogs. An in vitro model of echinocytosis induced by venom of crotalus atrox (western diamondback rattlesnake) was established to characterize erythrocyte morphologic changes and to investigate potential mechanisms of echinocytic transformation. Erythrocyte morphologic changes produced after the addition of venom to canine, feline, equine, and human blood were characterized by dose-dependent echinocytosis. Type III echinocytosis were consistently induced in vitro at a dose comparable to in vivo envenomation; higher venom doses produced spheroechinocytic and spherocytic transformations. The changes could not be induced in vitro in the presence of ethylenediaminetraacetic acid but were observed in heparinized and citrated blood samples, suggesting the participation of calcium or a metalloprotein in echinocytic change. These findings suggest that phospholipase A2 (PLA2), a calcium-dependent enzyme in snake venom, may be responsible for echinocytic transformation via the production of lysolecithin, a known echinocytic agent. Purified PLA2 from C. atrox venom induced dose-dependent echinocytic change in vitro in canine blood. Other potential mechanisms of echinocytic change evaluated in canine blood included erythrocyte cation loss and erythrocyte ATP depletion. In canine blood mixed with venom, erythrocyte sodium and potassium concentrations were consistently less than those of controls, likely as a result of membrane alteration produced by the actions of PLA2. There was no difference in blood ATP concentrations from dogs with snakebite when compared with normal controls; however, the power of this comparison was low. Echinocytosis induced by rattlesnake venom is related to the degree of venom exposure and may correlate clinically with the amount of venom absorbed. Echinocytic transformation in vitro is induced by PLA2 present in venom.
    Veterinary Pathology 10/1997; 34(5):442-9. · 2.04 Impact Factor
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    ABSTRACT: Few controlled studies have been made of the possible mechanisms and physiological consequences of weight gain after cats have been neutered. In this study, six male and six female cats were gonadectomised and compared with five entire male and six entire female cats, before they were neutered and one and three months later. The neutered males gained significantly more weight (mean [SEM] per cent) than the entire males (30.2 [5.2] v 11.8 [2.3]) and the entire females gained 40.0 (7.3) v 16.1 (3.3) per cent, (P < 0.05). The castrated males gained more weight as fat than the sexually intact males (22.0 [3.3] v 8.8 [4.5] per cent, P < 0.05). There was a significant increase (P < 0.05) in daily food intake after neutering. Spayed females underwent a significant decrease in fasting metabolic rate (83.7 [5.5] v 67.2 [2.3] kcal/kg bodyweight0.75/day P < 0.05). Gonadectomy had minimal effects on serum thyroid hormone concentrations, the resting or fasting metabolic rates in males, or on indices of glucose tolerance.
    Research in Veterinary Science 03/1997; 62(2):131-6. · 1.51 Impact Factor
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    D H Gould, B A Cummings, D W Hamar
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    ABSTRACT: Two groups of 3 120-160-kg Holstein steers were fed a diet high in carbohydrate and low in long fiber and either with or without added sodium sulfate. Prior to and during the course of feeding the experimental diet, the concentrations of rumen hydrogen sulfide gas and rumen fluid sulfide were determined by a simple sulfide detector tube method and by sulfide-selective electrode, respectively. Other measurements included rumen fluid pH, blood creatine kinase, and blood sulfhemoglobin. Two of the 3 steers fed the high-sulfate diet developed signs and lesions of polioencephalomalacia. Clinical signs included episodic ataxia and blunted or absent menace reaction. Increased ruminal H2S gas concentrations occurred in all 3 steers consuming the diet with added sulfate. The onset of clinical signs coincided with the onset of elevated H2S concentrations. These increases were 40-60 times the values measured in the steers consuming the diet without added sulfate. In contrast, increases in rumen fluid sulfide concentrations usually rose to 4 times that of control steers. The steers fed an identical diet but without added sulfate exhibited no signs or lesions of polioencephalomalacia and no elevations of sulfide in rumen gas or fluid. All steers had a modest decrease in rumen fluid pH associated with the transition to the concentrate diet. No significant changes were observed in any of the blood measurements of any of the steers. An additional pair of steers was fed the experimental diet with or without added sulfate to compare the ruminal H2S gas concentrations estimated by H2S detector tubes with those estimated by a different method of analysis utilizing charcoal trapping of H2S, conversion to sulfate, and measurement of the sulfate. Both methods yielded comparable estimates of H2S concentration. Overall, these data indicate that changes in rumen gas cap H2S concentrations are larger than changes in rumen fluid sulfide concentration and the estimation of rumen gas cap H2S concentration may be a practical approach to detecting pathologic increases in ruminal H2S gas. This simple, rapid, minimally invasive method should be useful for estimating the H2S content of ruminal gas under field conditions.
    Journal of veterinary diagnostic investigation: official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc 02/1997; 9(1):72-6. · 1.23 Impact Factor
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    ABSTRACT: To evaluate safety and efficacy of 4-methylpyrazole (4-MP) treatment in dogs and to determine clinical signs and outcome of, and clinicopathologic abnormalities in, dogs treated in early or late stages of ethylene glycol (EG) intoxication. Retrospective study. 107 dogs. For dogs treated with 4-MP, 1 of 2 dosage regimens was usually used: 20 mg/kg of body weight, IV, initially, 15 mg/kg 17 hours later, and 5 mg/kg 25 and 36 hours after the initial dose, or 20 mg/kg, IV, initially, 15 mg/kg 12 and 24 hours later, and 5 mg/kg 36 hours after the initial dose. Neither adverse clinical signs nor clinicopathologic abnormalities were associated with the administration of 4-MP except in 1 dog, which developed tachypnea, gagging, excess salivation, and trembling after the second dose of 4-MP was given. Ethylene glycol intoxication was confirmed in 37 dogs. Of these, 21 were azotemic or became azotemic within 18 hours after admission, and only 1 of the 21 survived. All 16 dogs that did not become azotemic survived. Median time from EG ingestion to treatment with 4-MP was 5 hours (range, 2 to 8.5 hours) for dogs that were not azotemic at admission and 14.5 hours (range, 8.5 to 38 hours) for dogs that were azotemic at admission. 4-MP was a safe and effective treatment for EG intoxication when it was given before sufficient quantities of EG had been metabolized to induce renal failure. Dogs treated within 8 hours of EG ingestion had a good prognosis.
    Journal of the American Veterinary Medical Association 01/1997; 209(11):1880-3. · 1.67 Impact Factor
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    ABSTRACT: Holstein steers were fed carbohydrate-rich, short-fiber basal diets with and without added sodium sulfate. Steers fed the high-sulfate diet developed the CNS disorder polioencephalomalacia (PEM). The onset of signs of PEM was associated with increased sulfide concentration in the rumen fluid. Over the course of the disease, anaerobic rumen bacteria were enumerated in roll tubes by use of the Hungate method Lo determine the effect of dietary sulfate on sulfate-reducing bacterial numbers. Media used included a general type for total counts and sulfate containing media with and without cysteine to assess sulfate-reducing bacteria. Changes in total and sulfate reducing bacterial numbers attributable to dietary sulfate content were not observed. The capacity to generate hydrogen sulfide from sulfate in fresh rumen fluid in vitro was substantially increased only after steers had been fed the high sulfate diet for 10 to 12 days, which coincided with the onset of signs of PEM. The low capacity for hydrogen sulfide production of rumen fluid taken at earlier times in the feeding period suggests that rumen microorganisms must adapt to higher dietary sulfate content before they are capable of generating potentially toxic concentrations of sulfide.
    American Journal of Veterinary Research 11/1995; 56(10):1390-5. · 1.21 Impact Factor
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    ABSTRACT: To study their role in sulfate reduction, anaerobic bacteria were cultured from rumen fluid samples of cattle fed high-carbohydrate, short-fiber diets with and without added sulfate. The steers fed the diet with added sulfate developed polioencephalomalacia. Microbiological methods included colony type profiles, molybdate sensitivity, presence of desulfoviridin, sulfate reduction rates of pure and mixed cultures, and incubation time effects on sulfate reduction. Colony-type profiles indicated decreased diversity, but no relative change in numbers of sulfate-reducing bacteria in rumen fluid from cattle fed diets with and without added sulfate. Thirteen bacteria] isolates were selected for further study on the basis of colony type, sulfate-reducing activity, and growth in lactate, sulfate, and yeast extract media. Seven of the isolates had Desulfovibrio-like characteristics (ie, they were gram-negative, motile rods that reduced sulfate, were inhibited by molybdate, and contained the pigment desulfoviridin). The remaining 6 isolates were gram-negative, nonmotile rods. Four of these released sulfide from cysteine, and 2 generated only limited amounts of sulfide from sulfate or cysteine. The 7 sulfate reducing isolates generated sulfide in rumen fluid broth medium at greater rates than those observed in fresh rumen fluid. Sulfate reduction Could be sustained in cultures for prolonged incubation times if the gas phase containing hydrogen sulfide was replaced at frequent intervals. Variations in the amount of sulfate reduced by the pure cultures were most pronounced at short incubation times. Sulfate reduction was not inhibited in mixed cultures of sulfate-reducing and nonsulfate-reducing bacteria.
    American Journal of Veterinary Research 11/1995; 56(10):1384-9. · 1.21 Impact Factor
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    ABSTRACT: Twenty forage samples were collected and selected for variation in nitrate content. Each forage samples was analyzed 4 times by 4 different methods: diphenylamine spot plate, spectrophotometric, nitrate-selective electrode, and high-performance liquid chromatographic. Five feed extracts were spiked with 2 different amounts of nitrate and analyzed by each method. The spectrophotometric and nitrate-selective electrode had similar percent recoveries, which were close to 100%. The nitrate-selective electrode method had the least variation of the 4 methods. The diphenylamine spot plate method had the poorest average recovery, greatest variation, and was the least accurate. The average coefficients of variation for all samples within a method were 15%, 12%, 6.4%, and 16 for the diphenylamine spot plate, spectrophotometric, nitrate-selective electrode, and high-performance liquid chromatographic methods, respectively. The variation in the nitrate-selective electrode method was lower (P < 0.05) than the other methods. The results from this study suggest that the nitrate-selective electrode method is more accurate and precise than the other methods of analysis tested.
    Journal of veterinary diagnostic investigation: official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc 10/1995; 7(4):527-30. · 1.23 Impact Factor
  • S M Dial, M A Thrall, D W Hamar
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    ABSTRACT: 4-Methylpyrazole (4-MP), an alcohol dehydrogenase inhibitor, was administered to dogs to treat ethylene glycol (EG) intoxication. Eleven dogs were given 10.6 g of EG/kg of body weight; 5 dogs were treated with 4-MP 5 hours after EG ingestion and 6 dogs were treated with 4-MP 8 hours after EG ingestion. 4-Methylpyrazole was administered IV as a 50-mg/ml [corrected] solution in 50% polyethylene glycol: initial dose, 20 mg/kg; at 12 hours after initial dose, 15 mg/kg; at 24 hours after initial dose, 10 mg/kg; and at 30 hours after initial dose, 5 mg/kg. Physical, biochemical, hematologic, blood gas, serum and urine EG concentrations, and urinalysis findings were evaluated at 0, 1, 3, 6, 9, 12, 24, 48, 72 hours, and at 1 week and 2 weeks after EG ingestion. Dogs of both groups developed clinicopathologic signs associated with EG intoxication, including CNS depression, hyperosmolality, high anion gap metabolic acidosis, polydipsia, polyuria, calcium oxalate monohydrate and dihydrate crystalluria, and isosthenuria. Fractional excretion of sodium was increased in all dogs between 1 and 9 hours after EG ingestion, but remained increased beyond 24 hours only in the 2 dogs treated at 8 hours after EG ingestion that developed acute renal failure. All dogs treated 5 hours after EG ingestion recovered without morphologic, biochemical, or clinical evidence of renal impairment. Of the 6 dogs treated 8 hours after EG ingestion, 2 developed acute renal failure. One of the dogs treated 8 hours after EG ingestion remained isosthenuric for 2 months, but did not manifest any other signs of renal impairment.(ABSTRACT TRUNCATED AT 250 WORDS)
    American Journal of Veterinary Research 01/1995; 55(12):1762-70. · 1.21 Impact Factor

Publication Stats

544 Citations
66.09 Total Impact Points

Institutions

  • 1988–2010
    • Colorado State University
      • • Department of Environmental & Radiological Health Sciences
      • • College of Veterinary Medicine and Biomedical Sciences
      • • Department of Clinical Sciences
      Fort Collins, Colorado, United States