Search Results

Abstract

Objective—To evaluate complications and outcomes associated with use of gastrostomy tubes in dogs with renal failure.

Design—Retrospective study.

Animals—56 dogs.

Procedure—Medical records were reviewed for dogs with renal failure that were treated by use of gastrostomy tubes.

Results—Mean ± SD BUN concentration was 134 ± 79 mg/dl and mean serum creatinine concentration was 9.0 ± 3.8 mg/dl. Low-profile gastrostomy tubes were used for initial placement in 10 dogs, and traditional gastrostomy tubes were used in 46 dogs. Mild stoma-site complications included discharge, swelling, erythema, and signs of pain in 26 (46%) of dogs. Twenty-six gastrostomy tubes were replaced in 15 dogs; 11 were replaced because of patient removal, 6 were replaced because of tube wear, and 3 were replaced for other reasons. Six tubes were replaced by low-profile gastrostomy tubes. Gastrostomy tubes were used for 65 ± 91 days (range, 1 to 438 days). Eight dogs gained weight, 11 did not change weight, and 17 lost weight; information was not available for 20 dogs. Three dogs were euthanatized because they removed their gastrostomy tubes, 2 were euthanatized because of evidence of tube migration, and 1 died of peritonitis.

Conclusions and Clinical Relevance—Gastrostomy tubes appear to be safe and effective for improving nutritional status of dogs with renal failure. (J Am Vet Med Assoc 2000;217:1337–1342)

Abstract

Objective—To determine signalment, history, clinical signs, blood and plasma taurine concentrations, electrocardiographic and echocardiographic findings, treatment, and outcome of dogs with low blood or plasma taurine concentrations and dilated cardiomyopathy (DCM).

Design—Retrospective study.

Animals—12 client-owned dogs with low blood or plasma taurine concentrations and DCM.

Procedure—Medical records were reviewed, and clinical data were obtained.

Results—All 12 dogs were being fed a commercial dry diet containing lamb meal, rice, or both as primary ingredients. Cardiac function and plasma taurine concentration improved with treatment and taurine supplementation. Seven of the 12 dogs that were still alive at the time of the study were receiving no cardiac medications except taurine.

Conclusions and Clinical Relevance—Results suggest that consumption of certain commercial diets may be associated with low blood or plasma taurine concentrations and DCM in dogs. Taurine supplementation may result in prolonged survival times in these dogs, which is not typical for dogs with DCM. Samples should be submitted for measurement of blood and plasma taurine concentrations in dogs with DCM, and taurine supplementation is recommended while results of these analyses are pending. (J Am Vet Med Assoc 2003;223:1137–1141)

Abstract

Objective—To determine effects of lipoic acid, vitamin E, and cysteine before and after oxidant challenge in cats.

Animals—24 sexually intact adult cats.

Procedure—Cats were allocated into 4 equal groups. For 25 weeks, group A was fed a control dry diet and groups B, C, and D received this diet supplemented with vitamin E (2,200 U/kg [dry matter basis {DMB}]) plus cysteine (9.5 g/kg [DMB]), lipoate (150 mg/kg [DMB]), or all 3 antioxidants together, respectively. Weights were measured every 3 days and venous blood obtained every 5 weeks for CBC; serum biochemical analyses; lymphocyte blastogenesis; thiobarbituric acid reactive substances concentration; and concentrations of plasma protein carbonyl, 8-OH dguanosine, blood glutathione, plasma amino acid, lipoate, and dihydrolipoate. At 15 weeks, all cats received acetaminophen (9 mg/kg, PO, once), clinical effects were observed, and methemoglobin concentrations were measured.

Results—Lymphocyte blastogenesis increased transiently in group C and D cats. After acetaminophen administration, all groups had transient increases in methemoglobin within 4 hours and mild, brief facial edema; group C had decreased glutathione concentration and increased 8-OH d-guanosine concentration versus controls; and protein carbonyl concentration increased least for group B. Plasma lipoate and dihydrolipoate concentrations peaked by week 10 for groups C and D.

Conclusions and Clinical Relevance—Lipoate, vitamin E, and cysteine did not have synergistic effects. Lipoate supplementation (150 mg/kg [DMB]) did not act as an antioxidant but appeared to enhance oxidant effects of acetaminophen. Vitamin E plus cysteine had protective effects. (Am J Vet Res 2005;66:196–204)

Abstract

Objective—To determine whether oral administration of L-lysine to cats would lessen the severity of conjunctivitis caused by feline herpesvirus (FHV-1).

Animals—8 healthy young adult cats.

Procedure—Cats received oral administration of lysine monohydrochloride (500 mg, q 12 h) or placebo (lactose) beginning 6 hours prior to inoculation of virus. The left conjunctival sac received a 50-µl suspension of FHV-1 grown in cell culture (1.8 X 10⁸ tissue culture infective dose₅₀) on day 1. Cats were evaluated and scores given for clinical signs each day for 21 days. Samples for virus isolation were collected from the eye and throat every third day. Plasma lysine and arginine concentrations were measured prior to the study and on days 3, 14, and 22.

Results—Cats that received lysine had less severe conjunctivitis than cats that received placebo. Virus isolation results did not differ between the groups. Plasma lysine concentration was significantly higher in cats that received lysine, compared with control cats, whereas plasma arginine concentrations did not differ between groups.

Conclusion and Clinical Relevance—Oral administration of 500 mg of lysine to cats was well tolerated and resulted in less severe manifestations of conjunctivitis caused by FHV-1, compared with cats that received placebo. Oral administration of lysine may be helpful in early treatment for FHV-1 infection by lessening the severity of disease. (Am J Vet Res 2002;63:99–103)

Abstract

Objective—To validate a recently developed commercially available leptin radioimmunoassay (RIA) for use with feline serum and evaluate the relationship between serum leptin concentrations and body fat mass in domestic cats.

Animals—19 sexually intact male specific–pathogenfree domestic cats that weighed 3.8 to 7.1 kg and were 1.1 to 3.5 years old.

Procedure—Specificity for feline leptin was evaluated by use of gel filtration chromatography and reversephase high-performance liquid chromatography fractionation of serum. Body fat mass was determined by use of the deuterium oxide (D₂O) dilution method. Serum water D₂O enrichment was measured by use of gas-phase Fourier transform infrared spectroscopy.

Results—Body fat mass and percentage body fat ranged from 0.3 to 2.3 kg and 7.5 to 34.9%, respectively. Serum leptin concentrations were lower in the unfed versus the fed state and ranged between 1.6 and 4.9 ng/ml human equivalent (HE); mean ± SD value was 2.9 ± 0.2 ng/ml HE. Leptin concentrations increased with increasing body fat mass and percentage of body fat.

Conclusions—Leptin is in the serum of domestic cats in free (> 78%) and apparently bound forms. The relationship between body fat and serum leptin concentration was similar to that observed in humans and rodents and indicative of a lipostatic role for leptin in cats. Cats that have an overabundance of body fat appear to be less sensitive to the weight-normalizing action of leptin than cats of ideal body condition. (Am J Vet Res 2000;61:796–801)

Abstract

Objective—To determine the effectiveness of 3 antioxidants in preventing Heinz body anemia in cats.

Design—Prospective study.

Animals—44 specific-pathogen-free healthy cats.

Procedure—Cats were housed individually, divided randomly into 4 groups, and given the following orally every 12 hours: empty gelcaps (control cats), Nacetylcysteine (NAC, 100 mg/kg of body weight), vitamin E (d,l-α-tocopherol; 400 IU), or ascorbate (250 mg). After 2 weeks, Heinz bodies were induced by dietary onion powder (OP; 1% or 3% of dry matter) or propylene glycol (PG, 8% wt/vol in drinking water) for an additional 3 weeks. Intake of treated water or food was recorded daily. Body weight, PCV, Heinz body and reticulocyte percentages, reduced glutathione concentration, and total antioxidant status were measured twice weekly in all cats.

Results—Heinz body percentage and degree of anemia did not differ significantly among cats receiving antioxidants and control cats except in cats that ingested water containing PG, in which antioxidant supplementation was associated with a decrease in water intake. Of cats that were fed a diet that contained OP, cats that received NAC had significantly higher reduced glutathione concentrations, compared with other cats in the experiment. Total antioxidant status did not consistently correlate with antioxidant supplementation or type of oxidant administered (ie, OP or PG).

Conclusions and Clinical Relevance—Although the effect of antioxidant supplementation on Heinz body anemia in cats was minimal, antioxidants may have subclinical biochemical effects such as GSH sparing that may be important against milder forms of oxidative stress. (Am J Vet Res 2001;62:370–374)

Abstract

Objective—To determine taurine status in a large group of Newfoundlands related by environment, diet, or breeding to a dog with dilated cardiomyopathy and taurine deficiency.

Design—Prospective study.

Animals—19 privately owned Newfoundlands between 5 months and 11.5 years old that had been fed commercial dry diets meeting established nutrient recommendations.

Procedure—Diet histories were obtained, and blood, plasma, and urine taurine concentrations and plasma methionine and cysteine concentrations were measured. In 8 dogs, taurine concentrations were measured before and after supplementation with methionine for 30 days. Ophthalmic examinations were performed in 16 dogs; echocardiography was performed in 6 dogs that were taurine deficient.

Results—Plasma taurine concentrations ranged from 3 to 228 nmol/mL. Twelve dogs had concentrations < 40 nmol/mL and were considered taurine deficient. For dogs with plasma concentrations < 40 nmol/mL, there was a significant linear correlation between plasma and blood taurine concentrations. For dogs with plasma concentrations > 40 nmol/mL, blood taurine concentrations did not vary substantially. Taurine-deficient dogs had been fed lamb meal and rice diets. Retinal degeneration, dilated cardiomyopathy, and cystinuria were not found in any dog examined for these conditions. The taurine deficiency was reversed by a change in diet or methionine supplementation.

Conclusions and Clinical Relevance—Results indicate a high prevalence of taurine deficiency among an environmentally and genetically related cohort of Newfoundlands fed apparently complete and balanced diets. Blood taurine concentrations indicative of taurine deficiency in Newfoundlands may be substantially less than concentrations indicative of a deficiency in cats. (J Am Vet Med Assoc 2003;223:1130–1136)

Abstract

Objective—To characterize the effect of maintenance hemodialysis on plasma amino acid concentrations and to quantitate free amino acid losses into the dialysate during hemodialysis in healthy dogs.

Animals—8 healthy adult dogs.

Procedure—Five dogs received hemodialysis treatments 3 times per week for 4 weeks. Plasma amino acid concentrations were evaluated once per week for 4 weeks in each of the 5 dogs prior to hemodialysis (time 0), 90 minutes during hemodialysis, and immediately after hemodialysis (180 minutes). Total free amino acid concentrations and plasma amino acid concentrations (time 0, 90 minutes, and 180 minutes) in the dialysate were evaluated in 3 dogs that received 1 hemodialysis treatment.

Results—Significant time versus week interactions with any plasma amino acid were not detected; however, significant decreases in all plasma amino acid concentrations measured were detected at the midpoint of dialysis (46 ± 2%) and at the end of each dialysis session (38 ± 2%). Mean (± SEM) total free amino acid loss into the dialysate was 2.7 ± 0.2 g or 0.12 g/kg of body weight.

Conclusions and Clinical Relevance—Hemodialysis is associated with significant alterations in plasma amino acid concentrations and loss of free amino acids into the dialysate. Loss of amino acids into the dialysate, coupled with protein calorie malnutrition in uremic patients, may contribute to depletion of amino acid stores.(Am J Vet Res 2000;61:869–873)

Abstract

Objective—To assess effects of deficiency of lipoprotein lipase (LPL) on body condition scores and lean and fat body masses of adult cats.

Animals—12 cats without LPL mutations and 23 cats that were heterozygous or homozygous carriers of the Gly412Arg LPL mutation.

Procedure—Lean and fat body masses were estimated by use of body condition scores and change in enrichment of serum after IV administration of deuterium oxide. Mass spectroscopy and infrared absorbance methods were used to determine deuterium enrichment.

Results—Fat body mass (mean ± SD; 0.2 ± 0.1 kg) and percentage body fat (6.2 ± 1.4%) of homozygotes were significantly less than those of clinically normal cats and heterozygotes (0.7 ± 0.1 kg, 18.2 ± 1.6% and 0.5 ± 0.1 kg, 15.6 ± 1.7%, respectively). Homozygous offspring of homozygous dams had significantly less fat body mass (0.1 ± 0.1 kg) and percentage body fat (2.1 ± 1.0%) than homozygous offspring of heterozygous dams (0.3 ± 0.1 kg and 9.2 ± 1.7%, respectively). Lean body mass did not differ significantly among groups. For all groups, percentage body fat was significantly correlated with body condition score (r = 0.65), and body condition scores supported findings for fat body mass.

Conclusions and Clinical Relevance—Deficiency of LPL activity in cats diminishes stores of body fat. This is consistent with a low rate of de novo synthesis of fat. The effect of dam on body masses in mature LPLdeficient cats indicates nutrient programming of adipose formation during gestation or lactation. (Am J Vet Res 2001;62:264–269)