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Objectives The objectives for this study were to compare the body composition of adult indoor neutered domestic cats with outdoor intact cats with an ideal body condition score using dual-energy x-ray absorptiometry, and to report the body composition findings of free-roaming cats, as this has not been previously reported. Most domestic house cats differ from free-roaming cats as they are confined indoors and neutered. Indoor neutered cats have reduced activity and hormonal alterations that may result in lower muscle mass and higher body fat percentages vs outdoor intact cats, despite similar body condition scores. Methods Twenty-one outdoor intact cats (10 male, 11 female) were selected from a trap–neuter–return program and 16 indoor neutered domestic cats (10 male, six female) were client-owned. Inclusion criteria included an estimated age between 1 and 6 years, complete blood count, biochemistry panel, urinalysis, total thyroxine, feline leukemia virus/feline immunodeficiency virus screening and a body condition score of 4–5/9. Results Indoor neutered cats had a higher body fat percentage (22.1% [range 17.3–28.2%]) than outdoor intact cats (17.3% [range 10.0–33.6%]; P = 0.002). Indoor neutered male cats had a higher body fat percentage ( P Conclusions and relevance The results of this study suggest indoor confinement and neutering increase body fat percentage and bone mineral density in cats with an ideal body condition score.

Objectives The aim of the study was to evaluate overall dry matter, organic matter, crude protein, crude fat and gross energy digestibility of a feline commercial raw diet and a homemade raw diet compared with a canned, heat-processed diet. Methods Six domestic shorthair kittens (20–28 weeks old) were fed three different diets in a Latin square crossover design. Diet A was a commercially available, canned, heat-processed diet. Diet B was a complete commercial, prefrozen, raw diet (commercial raw), and diet C was a raw diet supplement mixed with ground raw meat obtained locally (homemade raw). Both diets A and B were formulated to meet nutritional profile levels for cats at all life stages. Kittens were given specific diet amounts to maintain a 2–4% weight increase per week. Food was measured before and after feedings to determine the amount eaten, and all feces were collected, weighed and frozen prior to submission. Composite food samples and all feces were submitted to a national laboratory for proximate analysis of crude protein, crude fiber, ash, crude fat, moisture and caloric density. Results Significantly higher digestibility of dry matter ( P Conclusions and relevance Higher dry matter, organic matter and protein digestibility was seen in two commercial raw diets compared with a heat-processed diet. Digestibility differences could have been due to variance in dietary protein, fat and carbohydrate concentrations between the diets, variance in dietary ingredients or quality, alterations in protein structure secondary to heat processing, as well as alterations in gastrointestinal flora. Future research examining digestibility in diets with the same macronutrient proportions and ingredients, and mechanisms for any differences, is warranted.

Objective—To develop morphometric equations for prediction of body composition and create a body fat index (BFI) to estimate body fat percentage in overweight and obese dogs. Design—Prospective evaluation study. Animals—83 overweight or obese dogs ≥ 1 year of age. Procedures—Body condition score (BCS) was assessed on a 5-point scale, morphometric measurements were made, and visual and palpation-based assessments and dual-energy x-ray absorptiometry (DEXA) were performed. Equations for predicting lean body mass, fat mass, and body fat as a percentage of total body weight (ie, body fat percentage) on the basis of morphometric measurements were generated with best-fit statistical models. Visual and palpation-based descriptors were used to develop a BFI. Predicted values for body composition components were compared with DEXA-measured values. Results—For the study population, the developed morphometric equations accounted for 98% of the variation in lean body mass and fat mass and 82% of the variation in body fat percentage. The proportion of dogs with predicted values within 10% of the DEXA values was 66 of 83 (80%) for lean body mass, 56 of 83 (68%) for fat mass, and 56 of 83 (67%) for body fat percentage. The BFI accurately predicted body fat percentage in 25 of 47 (53%) dogs, whereas the value predicted with BCS was accurate in 6 of 47 (13%) dogs. Conclusions and Clinical Relevance—Morphometric measurements and the BFI appeared to be more accurate than the 5-point BCS method for estimation of body fat percentage in overweight and obese dogs. Further research is needed to assess the applicability of these findings to other populations of dogs. (J Am Vet Med Assoc 2014;244:1279–1284)

Objective—To develop morphometric equations for prediction of body composition and create a body fat index (BFI) system to estimate body fat percentage in overweight and obese cats. Design—Prospective evaluation study. Animals—76 overweight or obese cats ≥ 1 year of age. Procedures—Body condition score (BCS) was determined with a 5-point scale, morphometric measurements were made, and dual-energy x-ray absorptiometry (DEXA) was performed. Visual and palpation-based evaluation of various body regions was conducted, and results were used for development of the BFI system. Best-fit multiple regression models were used to develop equations for predicting lean body mass and fat mass from morphometric measurements. Predicted values for body composition components were compared with DEXA results. Results—For the study population, prediction equations accounted for 85% of the variation in lean body mass and 98% of the variation in fat mass. Values derived from morphometric equations for fat mass and lean mass were within 10% of DEXA values for 55 of 76 (72%) and 66 of 76 (87%) cats, respectively. Body fat as a percentage of total body weight (ie, body fat percentage) predicted with the BCS and BFI was within 10% of the DEXA value for 5 of 39 (13%) and 22 of 39 (56%) cats, respectively. Conclusions and Clinical Relevance—The BFI system and morphometric equations were considered accurate for estimation of body composition components in overweight and obese cats of the study population and appeared to be more useful than BCS for evaluation of these patients. Further research is needed to validate the use of these methods in other feline populations. (J Am Vet Med Assoc 2014;244:1285–1290)

Objective—To evaluate the influence of acidifying or alkalinizing diets on bone mineral density and urine relative supersaturation (URSS) with calcium oxalate and struvite in healthy cats. Animals—6 castrated male and 6 spayed female cats. Procedures—3 groups of 4 cats each were fed diets for 12 months that differed only in acidifying or alkalinizing properties (alkalinizing, neutral, and acidifying). Body composition was estimated by use of dual energy x-ray absorptiometry, and 48-hour urine samples were collected for URSS determination. Results—Urine pH differed significantly among diet groups, with the lowest urine pH values in the acidifying diet group and the highest values in the alkalinizing diet group. Differences were not observed in other variables except urinary ammonia excretion, which was significantly higher in the neutral diet group. Calcium oxalate URSS was highest in the acidifying diet group and lowest in the alkalinizing diet group; struvite URSS was not different among groups. Diet was not significantly associated with bone mineral content or density. Conclusions and Clinical Relevance—Urinary undersaturation with calcium oxalate was achieved by inducing alkaluria. Feeding an alkalinizing diet was not associated with URSS with struvite. Bone mineral density and calcium content were not adversely affected by diet; therefore, release of calcium from bone caused by feeding an acidifying diet may not occur in healthy cats.

Objectives The objective of this study was to determine if two raw feline diets were nutritionally adequate for kittens. Methods Twenty-four 9-week-old kittens underwent an Association of American Feed Control Officials’ (AAFCO) 10 week growth feeding trial with two raw diet groups and one cooked diet group (eight kittens in each). Morphometric measurements (weight, height and length), complete blood counts, serum chemistry, whole blood taurine and fecal cultures were evaluated. Results Overall, the growth parameters were similar for all diet groups, indicating the two raw diets used in this study supported feline growth, within the limitations of an AAFCO growth feeding trial. Kittens fed the raw diets had lower albumin ( P = 0.010) and higher globulin ( P = 0.04) levels than the kittens fed the cooked diet. These lower albumin levels were not clinically significant, as all groups were still within normal age reference intervals. A red cell microcytosis ( P = 0.001) was noted in the combination raw diet group. Increases in fecal Clostridium perfringens were noted in all groups, along with positive fecal Salmonella serovar Heidelberg and Clostridium difficile toxin in the combination raw diet group. Conclusions and relevance The majority of the parameters for feline growth were similar among all groups, indicating the two raw diets studied passed an AAFCO growth trial. In theory, it is possible to pass an AAFCO growth trial but still have nutrient deficiencies in the long term due to liver and fat storage depots. Some of the raw feeders had elevated globulin and microcytosis, likely associated with known enteropathogenic exposure. Disease risks to both pets and owners are obvious. Additional research in this area is needed to investigate the impact of raw diets on the health of domestic cats.

Background.Obesity has reached epidemic proportions in dogs and, as in humans, cost of care has increased due to associated comorbidities. In humans, asymptomatic urinary tract infections (UTI) may be more prevalent in the obese. Asymptomatic bacteriuria (AB) is the term used when UTI are asymptomatic. We hypothesized that morbidly obese dogs are similarly more likely to have asymptomatic bacteriuria than lean, overweight, and moderately obese dogs.Methods.A retrospective study was undertaken to explore a possible association between obesity and asymptomatic bacteriuria. Records from lean, overweight, and obese dogs receiving both a dual energy absorptiometry (DXA) scan and urine culture were included.Results.Six positive urine cultures were identified among 46 dogs fulfilling search criteria. All six positive cultures were found in dogs with body fat percentage of >45%. In dogs with body fat percentage of Discussion.There was an increased prevalence of asymptomatic bacteriuria in the morbidly obese dogs in this study compared to those that were lean, overweight, or moderately obese. Whether antibiotic therapy is necessary in such cases is still being debated, but because asymptomatic bacteriuria may be associated with ascending infections, uroliths, or other complications, the data reported herein support the screening of obese patients for bacteriuria.

Acceptance of feline commercial canned and raw-type moist foods was evaluated in 18 adult cats with and without dietary pre-exposure to the same moist foods in the postweaning period. We hypothesized that cats pre-exposed to moist foods would readily accept canned or raw foods on re-exposure as adults, despite consuming a commercial expanded dry food for a period of 7-23 months. A total of 13 cats were fed 1 of 3 moist foods (commercial canned, commercial raw, or homemade raw foods) exclusively between 9 and 20 weeks of age (exposed), and 5 adult cats were offered only dry food during the postweaning period (unexposed). All 18 cats were offered 1 of 3 moist foods as adults. The relative risk, confidence intervals, and P values were determined for weight maintenance and food intake between the exposed and nonexposed cats when they were fed moist foods as adults. Moist food acceptance was generally poor when offered to adult cats accustomed to eating an expanded dry diet for >7 months. There was no difference ( P = 0.61) in weight maintenance between those cats fed a moist food or expanded dry food as kittens and the later acceptance of a commercial canned or raw-type moist food as an adult. Similarly, adequacy of food intake measured as a proportion of estimated resting energy expenditure was not different between groups. The shorter the duration of dry food feeding, the greater was the likelihood of weight maintenance on reintroduction of moist foods. Kittens fed canned foods showed greater adaptability and acceptance of both raw and canned foods than those pre-exposed to either of the raw foods. In conclusion, prefeeding kittens a raw or canned food during the postweaning period between 9 and 20 weeks of age, followed by a period of dry foods for >7 months, did not increase later acceptance of the foods as an adult as compared with feeding expanded dry foods alone. Further studies with larger numbers of cats are needed to verify these observations and determine statistical significance.

Summary The incidence of canine obesity appears to be increasing dramatically and understanding factors impacting the amount of food pet owners provide their dogs may improve weight management. Human research has shown the size of food bowls, plates and utensils can significantly impact the amount of food portioned and consumed. This effect can be attributed to both the Delboeuf optical illusion and the Ebbinghaus-Titchener size-contrast illusion. To investigate the existence of a similar effect with dog owners, 54 dogs and their owners were recruited for a four treatment randomized prospective trial. Owners scooped out a normal kibble-based meal using a small bowl and small scoop, small bowl and large scoop, large bowl and small scoop or a large bowl and large scoop. Each treatment was used once per owner over four visits. Repeated measures anova revealed the mean amount of food portioned using the small bowl and small scoop was significantly less than all other bowl and scoop combinations (150.7 g vs. 171.5 g vs. 172.7 g vs. 184.5 g, p 0.05). Owners were more likely to portion a larger amount of food with a large bowl and large scoop. Results are consistent with human data and emphasize the need for owners to use standard measuring cups. Results also suggest owner compliance during weight loss programs may be improved with smaller bowls and serving scoops.

Problem statement: Adiponectin is a hormone expressed from adipose tissue in people, rodents and dogs. Adiponectin has anti-inflammatory action with beneficial effects on cardiovascular health and insulin sensitivity. With increasing fat mass, adiponectin concentrations paradoxically decrease. Adiponectin’s role in metabolism and diabetes mellitus is of interest in feline medicine because cats are susceptible to developing type II diabetes with weight gain. This study determined relative amounts of adiponectin mRNA expression from various body tissues and organs in domestic cats. Approach: Two intact male cats and one intact female cat were evaluated post-mortem. All cats were estimated to be young adults and had lean body conditions. Tissues samples from inguinal subcutaneous adipose, visceral mesenteric adipose, liver, skeletal muscle, cardiac muscle, aorta, stomach fundus, duodenum, pancreas, thyroid gland, adrenal gland (cortex and medulla) and renal cortex were collected and frozen. Following RNA extraction, adiponectin mRNA expression of each tissue was detected using Reverse Transcriptase (RT) real-time (Q) PCR. Results: Visceral adipose tissue had the highest level of expression, averaging 12% higher than subcutaneous adipose. All other tissues had negligible levels of expression compared to adipose samples. Conclusion: This study provided a valuable step for adiponectin research in cats by determining which tissues express this hormone. Cats differ from human beings by expressing higher levels of adiponectin in visceral compared to subcutaneous fat. The metabolic impact of this expression pattern is not known and provides a basis for future research.

Objective—To compare blood glucose concentrations measured with 2 portable blood glucose meters (PBGMs) validated for use in dogs (PBGM-D) and humans (PBGM-H) and an automated chemistry analyzer. Design—Validation study. Sample Population—92 samples of fresh whole blood and plasma from 83 dogs with various diseases. Procedures—Each PBGM was used to measure whole blood glucose concentration, and the automated analyzer was used to measure plasma glucose concentration. Passing-Bablok linear regression and Bland-Altman plots were used to determine correlations and bias between the PBGMs and the automated analyzer. Calculated acceptability limits based on combined inherent instrument imprecision were used with Bland-Altman plots to determine agreement. Clinical relevance was assessed via error grid analysis. Results—Although correlation between results of both PBGMs and the standard analyzer was > 0.90, disagreement was greater than could be explained by instrument imprecision alone. Mean difference between PBGM-H and chemistry-analyzer values was −15.8 mg/dL. Mean difference between PBGM-D and chemistry-analyzer values was 2.4 mg/dL. Linear regression analysis revealed proportional bias of PBGM-H (greater disagreement at higher glucose concentrations); no proportional bias was detected for PBGM-D. No constant bias was detected for either PBGM. Error grid analysis revealed all measurements from both PBGMs were within zones without an anticipated effect on clinical outcome. Conclusions and Clinical Relevance—Neither PBGM had exact agreement with the automated analyzer; however, the disagreement detected did not have serious clinical consequences. Our findings stressed the importance of using the same device for monitoring trends in dogs and using instrument-specific reference ranges.

We investigated hepatic gene expression in dogs with experimentally induced nutritional iron deficiency (ID). Our hypothesis was that ID would result in decreased hepcidin gene expression, and possibly in altered expression of other genes associated with iron metabolism.Liver biopsies were collected from each of 3 dogs before induction of ID, at the point of maximal ID, and after resolution of ID. Using Affymetrix microarray technology and analytical tools specifically designed for microarray data, we identified genes that had at least a 2-fold change in expression in response to ID. Four genes were selected for further analysis by reverse transcriptase PCR (RT-PCR).Dogs with ID had markedly decreased expression of the hepcidin gene (mean decrease of 40-fold for one probe and100-fold for another probe) and increased expression of the transferrin receptor gene (mean increase of7-fold). There was also mildly decreased expression of the "similar to calreticulin" gene and a gene of unknown function. Results of RT-PCR analysis were consistent with microarray findings.Changes in hepcidin and transferrin receptor gene expression were consistent with the known biology of iron metabolism. The decrease in expression of a gene identified as "similar to calreticulin," while not statistically significant, was consistent with the findings of other investigators that suggest iron plays a role in calreticulin expression.

The objectives of this study were to evaluate the effects of dirlotapide, a microsomal triglyceride transfer protein inhibitor, on apparent nutrient digestibility of an expanded dry dog food, on defecation frequency and fecal consistency. Eighteen beagles were randomized to either placebo (n = 6) or dirlotapide (n = 12). Testing was divided into a 21-day adaptation phase (days -21 to -1) and a 35-day treatment (digestibility testing) phase (days 0-35). During the treatment phase, dogs were administered oral dirlotapide (0.3 mg/kg) or placebo (0.06 mL/kg) once daily. For digestibility testing, feces were collected over two periods for 7 days each starting on days -9 and 28. All dogs were fed a commercial adult dog food throughout the study. Food intake was adjusted to maintain body weight during adaptation, followed by pair-feeding placebo dogs the amount of food ingested by the dirlotapide dogs during the treatment period. Dogs in both groups had reduced food intake and lost similar amounts of body weight during treatment. Dogs receiving 0.3 mg dirlotapide/kg once daily had a small but significant (P = 0.018) decrease (6.16 +/- 2.22%, mean +/- SD) in crude fat digestibility compared with the placebo-treated food-restricted dogs, but no difference in crude protein, dry matter, or energy digestibility was observed. Fecal consistency and volume and defecation frequency were similar between groups. Dirlotapide effectively reduced appetite and energy intake without affecting nutrient digestibility, except for a minimal decrease in fat digestibility.

The purpose of this study was to characterize light and electron microscopic findings from 9 dogs that had consumed aflatoxin-contaminated commercial dog food from recalled batches. Four dogs died and 5 were euthanized after signs of liver failure. Analysis of feed and liver samples confirmed exposure to aflatoxin. Of the 9 dogs, 8 had classic signs of liver failure, and 1 had signs of liver failure. Enlarged, pale yellow livers were seen macroscopically at necropsy in the dogs with subacute hepatopathy, and cirrhosis was noted in the dog with chronic hepatopathy. Histopathologic findings included hepatic lipidosis, portal fibroplasia, and biliary hyperplasia, which supported a diagnosis of subacute toxic hepatopathy in the 8 symptomatic animals. Marked lobular atrophy, bridging portal fibrosis, and regenerative hepatocellular nodules characterized the dog with chronic hepatopathy. Electron microscopy revealed marked hepatocellular lipid vacuolation and early fibroplasia in the dogs with acute hepatopathy and marked fibrosis and regeneration in the dog with chronic hepatopathy. Analysis of feed for aflatoxin consistently revealed high levels of aflatoxin B1 (range of 223–579 ppb), and hepatic tissue contained elevated levels of aflatoxin B1metabolite M1 (0.6–4.4 ppb). Although dogs are not commonly affected by aflatoxicosis, they are highly susceptible and can present with classic signs of acute or chronic hepatopathy. Characteristic gross, histologic, and electron microscopic changes help pathologists determine a presumptive toxic insult. Detecting aflatoxins or their metabolites in feed or liver specimens can help confirm the diagnosis of aflatoxicosis.

Treatment of diabetes mellitus (DM) in the cat relies primarily on the adequate insulin therapy and controlled dietary intake. The goals of managing DM in the cat have changed from attaining glycemic control to achieving diabetic remission (transient diabetes) in a large proportion of cases. Remission rates of up to 68% have been published. The used of low-carbohydrate foods for cats improves the odds of achieving diabetic remission by fourfold. Nonetheless, some cats show an improved response to high-fiber food. Clinical judgement, trial, and personal preference to currently dictate which diet to offer an individual animal.

Lower urinary tract disease occurs commonly in cats and is often associated with crystal-related disease. Dietary modification is beneficial in managing some of these diseases, including idiopathic cystitis, urolithiasis, and urethral matrix-crystalline plugs. Altering dietary formulation may result in decreasing urinary concentrations of crystallogenic compounds, increasing urinary concentrations fo crystallogenic inhibitors, and diluting urine composition.

Objective: To describe the medical and nutritional management of a 4-year-old Weimaraner with acute hepatic failure and immune-mediated hemolytic anemia (IMHA) associated with consuming a commercial dog food. Case summary: A 4-year-old male castrated Weimaraner developed signs of IMHA, hepatic failure, disseminated intravascular coagulopathy, and malnutrition after consuming a commercial dog food. During the course of hospitalization, medical management included immunosuppressive therapy and supportive care. Nutritional support consisted of both enteral and parenteral nutrition. The dog was discharged after 19 days of hospitalization and fully recovered by 6 months. An investigation by the Food and Drug Administration was not able to determine the exact cause of the acute hepatic failure and IMHA. New information provided: This is the first case report documenting the medical and nutritional management of a critically ill animal associated with ingestion of this commercial dog food.

BACKGROUND Reticulocyte indices, especially reticulocyte hemoglobin content (CH retic), have shown promise as markers of iron deficiency (ID), but there have been no prospective investigations of reticulocyte indices in experimental models of ID. OBJECTIVES The objective of this study was to compare reticulocyte indices with conventional hematologic and biochemical indices as markers of ID in dogs. METHODS Iron deficiency was induced in 7 dogs by feeding an iron-deficient diet, and corrected by restoring dietary iron and by giving iron parenterally. Blood samples were collected at weekly intervals. Results of hematologic and biochemical tests were compared using t-tests and receiver operator characteristic (ROC) curve analysis. RESULTS Comparing mean values on days 0 and 35, by which time hemoglobin concentration decreased to 90% of baseline in all dogs, % Macro retic, % Hypo retic, % Low CH retic, and % High CH retic differed by greater than 3-fold, whereas no conventional hematologic or biochemical indices differed by as much as 2-fold. Comparing conventional hematologic and reticulocyte indices by ROC curve analysis using 4 different biochemical diagnostic criteria of ID, CH retic, % Hypo retic, % Low CH retic, and % High CH retic had higher areas under the curve (AUC) than either MCV conv or MCHC conv according to all 4 criteria, and % Macro retic and MCV retic had higher AUC values according to 3 of 4 criteria (differences were not always statistically significant). CONCLUSIONS Results of this study support the value of reticulocyte indices in the diagnosis and monitoring of ID in dogs. Species similarities in the pathophysiology and hematologic manifestations of ID suggest these findings also may be relevant to ID in people.

This study compared the effects of a moderate carbohydrate–high fiber (MC–HF) food and a low carbohydrate–low fiber (LC–LF) food on glycemic control in cats with diabetes mellitus. Sixty-three diabetic cats (48 male castrated, 15 female spayed) were randomly assigned to be fed either a canned MC–HF ( n=32) food or a canned LC–LF ( n=31) food for 16 weeks. Owners were blinded to the type of diet fed. CBC, urinalysis, serum chemistry panel, fructosamine concentration and thyroxine concentration were determined on initial examination, and a complete blood count, serum chemistry panel, urinalysis and serum fructosamine concentration were repeated every 4 weeks for 16 weeks. Insulin doses were adjusted as needed to resolve clinical signs and lower serum fructosamine concentrations. Serum glucose ( P=0.0001) and fructosamine ( P=0.0001) concentrations significantly decreased from week 0 to week 16 in both dietary groups. By week 16, significantly more of the cats fed the LC–LF food (68%, 22/31), compared to the cats fed the MC–HF food (41%, 13/32), had reverted to a non-insulin-dependent state ( P=0.03). Cats in both groups were successfully taken off of insulin regardless of age, sex, type of insulin administered or duration of clinical disease before entering the study. There was no significant difference in the initial or final mean body weights or in the mean change in body weight from week 0 to week 16 between dietary groups. Diabetic cats in this study were significantly more likely to revert to a non-insulin-dependent state when fed the canned LC–LF food versus the MC–HF food.

Objective—To determine whether urine protein-to-creatinine ratio (UP:C) ≥ 1.0 at initial diagnosis of chronic renal failure (CRF) is associated with greater risk of development of uremic crises, death, and progression of renal failure in dogs. Design—Prospective cohort study. Animals—45 dogs with CRF. Procedure—Dogs were prospectively assigned to 2 groups on the basis of initial UP:C < 1.0 or ≥ 1.0. The association between magnitude of proteinuria and development of uremic crises and death was determined before and after dogs with initial UP:C ≥ 1.0 were assigned to 3 subgroups and compared with dogs with initial UP:C < 1.0. Changes in reciprocal serum creatinine concentration were used to estimate decrease in renal function. Results—Initially, dogs had similar clinical characteristics with the exception of systolic blood pressure and UP:C. Relative risks of development of uremic crises and death were approximately 3 times higher in dogs with UP:C ≥ 1.0, compared with dogs with UP:C < 1.0. Relative risk of adverse outcome was approximately 1.5 times higher for every 1-unit increment in UP:C. The decrease in renal function was of greater magnitude in dogs with UP:C ≥ 1.0, compared with dogs with UP:C < 1.0. Conclusions and Clinical Relevance—Initial UP:C ≥ 1.0 in dogs with CRF was associated with greater risk of development of uremic crises and death, compared with dogs with UP:C < 1.0. Initial determinations of UP:C in dogs with naturally occurring CRF may be of value in refining prognoses. (J Am Vet Med Assoc 2005;226:393–400)

Calcium oxalate has become the most common mineral occurring in canine and feline uroliths. Although calcium oxalate urolith formation may be a consequence of metabolic disease, the underlying cause is not identified in many dogs and cats. Currently, there is no successful medical dissolution protocol, and calcium oxalate uroliths must be removed physically if causing problems. Effective preventative protocols are available for dogs and cats, although they are not uniformly successful.

Ten client-owned cats with calcium oxalate (CaOx) urolithiasis were evaluated to determine the effect of diet on urine CaOx saturation. Two dietary treatments were evaluated in each cat: the diet consumed just prior to urolith detection and a canned diet formulated to prevent CaOx uroliths. This study revealed that hypercalciuria is a consistent abnormality in cats with CaOx urolith formation. When urolith-forming cats consumed a diet formulated to prevent urolith formation, activity product ratios for CaOx (which estimate the degree to which urine is saturated with CaOx) were significantly lower. These results suggest that consumption of an appropriately formulated urolith-prevention diet will reduce recurrence of CaOx urolithiasis.

Adiponectin is an important anti-inflammatory hormone secreted from adipose tissue. The high-molecular-weight form of adiponectin (HMW) closely correlates with insulin sensitivity in human beings. This study uses a novel method of size-exclusion gel chromatography combined with enzyme-linked immunosorbent assay to measure HMW feline adiponectin and determine its relationship to leptin, cholesterol, and insulin sensitivity as cats gain and lose weight. In addition, total adiponectin and its messenger RNA expression in subcutaneous adipose tissue were measured. No correlations were found between total serum adiponectin and subcutaneous adipose messenger RNA expression, fat mass, or measures of insulin sensitivity. This study demonstrates that cats have high percentages of HMW adiponectin. Although weak correlations between HMW adiponectin and fat mass were detected, additional cats are needed to determine if the correlations are significant.

Chromium is an essential dietary trace mineral involved in carbohydrate and lipid metabolism. Chromium is required for cellular uptake of glucose, and chromium deficiency causes insulin resistance. Chromium supplementation may improve insulin sensitivity and has been used as adjunct treatment of diabetes mellitus in humans. In this study, 13 dogs with naturally acquired diabetes mellitus were treated with insulin for 3 months, then with insulin and chromium picolinate for 3 months. Dogs weighing 15 kg (n = 4) received 200 microg of chromium picolinate once daily for 2 weeks, then 200 microg twice daily for 2 weeks, then 400 microg twice daily for 2 months. Type of insulin, frequency of insulin administration, and diet were kept constant, and insulin dosage was adjusted, as needed, to maintain optimal control of glycemia. Mean body weight, daily insulin dosage, daily caloric intake, 10-hour mean blood glucose concentration, blood glycated hemoglobin concentration, and serum fructosamine concentration were not markedly different when dogs were treated with insulin and chromium picolinate, compared with insulin alone. Adverse effects were not identified with chromium picolinate administration. Results of this study suggest that, at a dosage range of 20-60 microg/kg/d, chromium picolinate caused no beneficial or harmful effects in insulin-treated diabetic dogs.

Objective—To determine whether hydrochlorothiazide (HCTZ) reduces urinary calcium excretion in dogs with calcium oxalate urolithiasis. Design—Original study. Animals—8 dogs with calcium oxalate urolithiasis. Procedure—4 treatment protocols were evaluated in each dog (a low calcium, low protein diet designed to prevent calcium oxalate urolith formation with and without administration of HCTZ [2 mg/kg (0.9 mg/lb) of body weight, PO, q 12 h] and a maintenance diet with higher quantities of protein and calcium with and without administration of HCTZ). At the end of each 2-week treatment period, 24-hour urine samples were collected. Blood samples were collected during the midpoint of each urine collection period. Analysis of variance was performed to evaluate the effects of HCTZ and diet on urine and serum analytes. Results—Hydrochlorothiazide significantly decreased urine calcium and potassium concentration and excretion. Hydrochlorothiazide also significantly decreased serum potassium concentration. Compared with the maintenance diet, the urolith prevention diet significantly decreased urine calcium and oxalic acid concentration and excretion. Dogs consuming the urolith prevention diet had significantly lower serum concentrations of albumin and urea nitrogen. Conclusions and Clinical Relevance—Administration of HCTZ decreased urine calcium excretion in dogs with a history of calcium oxalate urolith formation. The greatest reduction in urine calcium concentration and excretion was achieved when dogs received HCTZ and the urolith prevention diet. Results of this study suggest that the hypocalciuric effect of HCTZ will minimize recurrence of calcium oxalate urolith formation in dogs; however, long-term controlled clinical trials are needed to confirm the safety and effectiveness of HCTZ. (J Am Vet Med Assoc 2001;218:1583–1586)

Objective—To determine hepatotoxicity of stanozolol in cats and to identify clinicopathologic and histopathologic abnormalities in cats with stanozololinduced hepatotoxicosis. Design—Clinical trial and case series. Animals—12 healthy cats, 6 cats with chronic renal failure, and 3 cats with gingivitis and stomatitis. Procedures—Healthy cats and cats with renal failure were treated with stanozolol (25 mg, IM, on the first day, then 2 mg, PO, q 12 h) for 4 weeks. Cats with gingivitis were treated with stanozolol at a dosage of 1 mg, PO, every 24 hours. Results—Most healthy cats and cats with renal failure developed marked inappetence, groomed less, and were less active within 7 to 10 days after initiation of stanozolol administration. Serum alanine transaminase (ALT) activity was significantly increased in 14 of 18 cats after stanozolol administration, but serum alkaline phosphatase activity was mildly increased in only 3. Four cats with serum ALT activity > 1,000 U/L after only 2 weeks of stanozolol administration had coagulopathies; administration of vitamin K resolved the coagulopathy in 3 of the 4 within 48 hours. All 18 cats survived, and hepatic enzyme activities were normal in all cats tested more than 4 weeks after stanozolol administration was discontinued. Two of the 3 cats with gingivitis developed evidence of severe hepatic failure 2 to 3 months after initiation of stanozolol treatment; both cats developed coagulopathies. Histologic evaluation of hepatic biopsy specimens from 5 cats revealed diffuse hepatic lipidosis and cholestasis without evidence of hepatocellular necrosis. Conclusions and Clinical Relevance—Results suggest that stanozolol is hepatotoxic in cats. (J Am Vet Med Assoc 2000;217:681–684)

Formation of uroliths is not a disease but rather a complication of several disorders. Some disorders can be identified and corrected (e.g., infection-induced struvite urolith formation), and some can be identified but not corrected (e.g., hyperuricosuria occurring in Dalmatians that form ammonium urate uroliths), although for others, the underlying etiopathogenesis is not known (e.g., calcium oxalate urolith formation in Miniature Schnauzers). A common denominator of these disorders is that from time to time, they can create oversaturation of urine with one or more crystal precursors, resulting in formation of crystals. To develop rational and effective approaches to treatment, abnormalities that promote urolith formation must be identified with the goal of eliminating or modifying them. It is therefore important to understand several basic concepts associated with urolithiasis.

Gastric emptying in 18 healthy cats was assessed simultaneously using scintigraphy and barium-impregnated polyethylene spheres (BIPS®). Canned Prescription Diet(r) Feline c/d(r) (Hill's Pet Nutrition, Inc., Topeka, KS) labeled with 99mTc-disofenin (Hepatolite, DuPont Merck Pharmaceutical Co., Billerica, Mass.) was fed on four separate days, Scintigraphic images were obtained at time 0 and then every 30 minutes to 6 hours. On the fourth scan day, 30 small (1.5 mm) and 10 large (5 mm) BIPS® (Chemstock Animal Health Ltd., Christchnrch, New Zealand) were mixed with the labeled meal, and in addition to scintigraphy, radiographs were made at 60-minute intervals for 6 hours. Gastric emptying was 11 to 15% slower on the day of simultaneous radiography as compared with the 3 days when only scintigraphy was performed (p≤ .05). Percentage retention of 1.5 mm BIPS® in the stomach was significantly greater than the percentage retained gastric activity at hours 1, 2, 3, 4, 5, and 6 (p≤ .05).BIPS® were clustered in the pyloric region of the stomach by 3 hours in all cats. In 10/18 animals, all BIPS® were retained in pyloric region of the stomach at 6 hours, despite observable decreased size of the gastric silhouette and ≤15% retained gastric activity. In conclusion, gastric emptying of 1.5-mm BIPS® does not parallel gastric emptying of 99mTc-disofenin labeled canned Prescription Diet(r) Feline c/d(r). Stress associated with radiography may delay gastric emptying. Diet type should be considered when evaluating clinical radiographic studies where BIPS® have been used.

American black bears (Ursus americanus) have been shown to become transiently insulin resistant and hypothyroid during winter, but no studies have investigated these changes in long-term captive bears or in bears which remain awake year-round. Wild, captive hibernating, and captive nonhibernating bears were evaluated at times corresponding to three of their major physiologic stages: fall (hyperphagic stage), winter (hibernation stage), and summer (normal activity stage). Combined insulin and glucose tolerance tests and thyroid hormone profiles were performed on all bears during each stage. All three groups of bears had evidence of insulin resistance during the winter, as compared to the summer or fall, based on glucose tolerance curves. Analysis of thyroid hormone concentration varied and distinct patterns or similarities were not apparent. While obesity in captive American black bears is multifactorial, the finding that, regardless of their ability to hibernate, captive bears retain similar physiology to their wild counterparts indicates that captive bears' complex physiologic changes need to be addressed in their management.

With the recent identification of non-insulin-dependent diabetes mellitus (NIDDM) in cats, new possibilities arise for the use of oral hypoglycaemic agents in the treatment of feline NIDDM, similar to their use in humans. To identify the future applicability of the oral hypoglycaemic agent, glipizide, in the treatment of feline NIDDM, its effects on serum insulin and glucose concentrations in healthy cats was examined. In addition, adverse effects seen clinically or on bloodwork following shortterm use of the drug were looked for. Serum insulin and glucose concentrations were evaluated after the oral administration of 2·5 5·0 and 10·0 mg glipizide and placebo in 10 healthy cats. For each drug trial, blood was obtained five minutes before, immediately before, and 7·5 15, 30, 45, 60, 90 and 120 minutes after glipizide or placebo administration. Mean serum insulin concentration increased after glipizide administration, with peak mean serum insulin concentration occurring 15 minutes after administration and declining to baseline by 60 minutes. There was no significant difference in peak mean serum insulin concentration, mean serum insulin concentration at 60 minutes after glipizide administration, or mean total insulin secretion between the three glipizide dosages. Mean serum glucose concentration decreased within 15 minutes of glipizide administration, with the glucose nadir occurring 60 minutes after glipizide administration. Placebo trials showed no significant change in mean serum insulin or glucose concentrations from baseline concentrations.

A privately owned, obese, adult female raccoon (Procyon lotor) presented with polyuria, polydipsia, weight loss, and increased appetite. Diabetes mellitus was diagnosed based on laboratory findings, including hyperglycemia and glucosuria. As a result of the raccoon's age and obesity at the onset of clinical signs, the raccoon was thought to have type 2 diabetes mellitus, a diagnosis that was supported by paired glucose tolerance tests. Treatment consisted of dietary management and daily insulin therapy. The raccoon was gradually weaned off insulin with no return of clinical signs, further verifying the characterization of type 2 diabetes mellitus.

Hydrochlorothiazide (1 mg/kg PO q12h) or placebo was administered to healthy cats for 2 weeks in a masked, placebo-controlled, crossover-design study, and 24-hour urine samples were collected. When cats received hydrochlorothiazide, 24-hour urine volume, ammonia, chloride, creatinine, magnesium, oxalic acid, phosphate, potassium, and sodium were significantly higher than when cats received placebo. Hydrochlorothiazide was associated with significantly lower urinary saturation for calcium oxalate, but no difference was found in 24-hour urine calcium and citrate, urinary saturation for struvite, or blood ionized calcium. Hydrochlorothiazide decreased urinary saturation for calcium oxalate and could be useful in managing cats with calcium oxalate uroliths. Results of this study, however, should not be extrapolated to cats that form calcium oxalate uroliths.

Prednisolone (10 mg PO q24h) or placebo was administered to healthy cats for 2 weeks in a masked, placebo-controlled, crossover-design study, and 24-hour urine samples were collected. When cats received prednisolone, 24-hour urine pH was lower and 24-hour urine excretion of creatinine, magnesium, phosphate, and potassium was higher than when cats received placebo. No significant difference was found in urinary relative supersaturation for calcium oxalate (CaOx) or struvite between treatment groups. Prednisolone administration did not induce diuresis, nor was it associated with increased calcium excretion or urinary saturation for CaOx in these healthy cats. Results of this study, however, should not be extrapolated to cats that form CaOx uroliths associated with idiopathic hypercalcemia.