Management of anorexia in the cat

One of the most frequent motivations for seeking veterinary attention for a cat is when the owner recognises a loss of normal appetite in his pet. The medical term for a lack of appetite for food is 'anorexia', and it may be partial or complete. While anorexia is a common manifestation of disease, the mechanisms underlying decreased food intake are complex and not completely understood. The regulation of appetite involves interaction of external stimuli with signals from the gastrointestinal tract and central nervous system. Aberrations in any of the internal control systems for hunger and satiety, or changes in external factors such as diet or feeding environment, can result in partial or total anorexia. The challenge for the practitioner is not only to diagnose and treat the underlying condition, but to recognise at what point inadequate food intake has or will impinge on the patient's nutritional status to the extent that it might deleteriously affect clinical outcome. It is also important to bear in mind the significance that the patient's appetite and food intake has for the cat owner in his overall perception of his pet's condition and quality of life.

An investigation of the relationship between caloric intake and outcome in hospitalized dogs

Malnutrition in veterinary patients is thought to increase morbidity and mortality, but this has not been statistically quantified. A study was designed to estimate the proportion of hospitalized canine patients in negative-energy balance; relate calories consumed in-hospital to appetite at home shortly after discharge; determine why these dogs were in a negative-energy balance; and assess the relationship between body condition score, physical status score (PSS), diagnosis, and caloric intake with patient outcome. Data were collected from 276 dogs over several days in one of the various referral hospitals. After eliminating partial hospital days, there were 821 dog-days for evaluation. A daily positive-energy balance (> 95% resting energy requirement) was achieved for only 27% of the 821 full dog-days. Of 226 dogs successfully followed after discharge, 83% were considered by their owners to have a normal appetite and/or food intake by the second day home. Of the 601 negative-energy-balance dog-days, 22% were due to poorly written feeding orders and 34% had orders to have feed withheld; most cases (44%) resulted from the dog refusing to eat any or all of the food offered. There were significant relationships between caloric intake and PSS, outcome and PSS, and outcome and caloric intake. In general, canine patients with lower PSSs (i.e., no or mild systemic diseases) consumed more daily calories and were more likely to be discharged whereas patients with higher PSSs (i.e., incapacitating, life-threatening systemic diseases) were less likely to meet the resting energy requirement and be discharged from the hospital.

Hypomagnesemia and hypocalcemia associated with protein-losing enteropathy in Yorkshire terriers: five cases (1992-1998)

OBJECTIVE

To determine clinical and laboratory findings associated with protein-losing enteropathy, hypomagnesemia, and hypocalcemia in Yorkshire Terriers.

DESIGN

Retrospective study.

ANIMALS

5 purebred or crossbred Yorkshire Terriers with protein-losing enteropathy, hypomagnesemia, and hypocalcemia.

PROCEDURE

Medical records were reviewed for dogs with protein-losing enteropathy, hypomagnesemia, and hypocalcemia.

RESULTS

Of 8 dogs with these signs, 5 had Yorkshire Terrier breeding. Common findings were diarrhea, abdominal effusion, leukocytosis, neutrophilia, hypocalcemia (ionized calcium), hypomagnesemia, hypoproteinemia, hypoalbuminemia, hypocholesterolemia, and increased serum activity of aspartate aminotransferase.

CONCLUSIONS AND CLINICAL RELEVANCE

Yorkshire Terriers are at increased risk for development of protein-losing enteropathy with hypomagnesemia and decreased ionized calcium concentration. Hypomagnesemia and hypocalcemia may have a related pathogenesis involving intestinal loss, malabsorption, and abnormalities of vitamin D and parathyroid hormone metabolism. Serum electrolyte replacement may be required to avoid neurologic and metabolic problems.

Effects of insoluble and soluble dietary fiber on glycemic control in dogs with naturally occurring insulin-dependent diabetes mellitus

OBJECTIVE

To evaluate the effects of diets differing in type and quantity of fiber on glycemic control in dogs with naturally occurring insulin-dependent diabetes mellitus.

DESIGN

Prospective randomized crossover controlled trial.

ANIMALS

7 dogs with well-regulated naturally occurring insulin-dependent diabetes mellitus.

PROCEDURE

Dogs were fed 1 of 3 diets for 1 month each in 1 of 6 randomized diet sequences. Diets included a low-fiber diet (LF) and 2 high-fiber diets; 1 contained only insoluble fiber (HIF), and 1 contained soluble fiber in addition to insoluble fiber (HSF). Caloric intake was unchanged throughout the study. Glycemic control was assessed after each feeding trial by measuring serum fructosamine concentration and performing 5 serial measurements of blood glucose concentration every 2 hours after the morning feeding and insulin injection.

RESULTS

Significant differences were not detected in body weight, required insulin dosage, or albumin concentration among dogs fed the HIF, HSF, and LF diets. Mean and maximum blood glucose concentrations and area under the blood glucose curve were significantly lower in dogs fed the HIF diet, compared with values in the same dogs fed the HSF or LF diet. Fructosamine concentration was significantly lower in dogs fed the HIF or HSF diet, compared with values in the same dogs fed the LF diet.

CONCLUSIONS AND CLINICAL RELEVANCE

In dogs with naturally occurring insulin-dependent diabetes mellitus, a dry, high insoluble-fiber diet may aid in glycemic control.

Subcutaneous emphysema, pneumoperitoneum, and pneumoretroperitoneum after gastrostomy tube placement in a cat

A 17-year-old spayed female domestic shorthair cat developed subcutaneous emphysema, pneumoperitoneum, and pneumoretroperitoneum during endoscopic placement of a gastrostomy feeding tube after gastric insufflation and cannula insertion. The cat underwent exploratory laparotomy to investigate the possibility of gastric rupture but only a 2- to 3-mm defect was found in the gastric fundus at the site of cannula insertion. Pasteurella multocida and Enterobacter spp were cultured aerobically from the peritoneal cavity. The cat recovered without complications.

Critical care nutrition: routes of feeding

Nutrition is an integral part of the management of the critically ill patient. Nutritional support can be provided by either parenteral or enteral routes. Whenever possible, enteral nutrition is the method of choice, as it reduces complication rates and improves outcome. Potential choices for enteral feeding include nasoesophageal, esophagostomy, gastrostomy, jejunostomy, and transpyloric feeding tubes. The modes of parenteral and enteral nutrition are reviewed individually, including indications and selection of appropriate routes of feeding, methods of tube placement, and benefits and risks associated with each feeding approach.

Interventional nutrition for the critical care patient: optimal diets

The classic goals of nutritional support have been to provide for the patient's ongoing nutritional needs and to preserve endogenous tissues from further catabolism. It is becoming increasingly clear that it also is possible to modulate metabolic and pathologic processes through the use of specific nutrients and metabolites and even the route by which nutrition is provided. This article discusses what is and is not known about the nutritional requirements of critically ill dogs and cats and some of the specific nutrients that are being used to enrich formulas for critically ill patients.

Automated, eight-cage indirect calorimetry in rats

We have constructed an automated, eight-cage indirect calorimeter (AIC) for the measurement of energy expenditure in rats. We compared the measurements of resting energy expenditure (REE) in rats during a 30-h fast obtained with the AIC with those obtained with a manual indirect calorimetry (MIC) system. There was both a high degree of correlation between the two techniques during the initial 18 h of the fast (r = 0.90, P < 0.05) and strong intertechnique agreement. REE (AIC) decreased during the final 12 h of the 30-h fast (79.6 +/- 2.7-72.0 +/- 4.4 kcal.kg-0.75.d-1 [mean +/- SD, P < 0.01]). REE (MIC) did not show a significant decrease during this part of the fast (79.7 +/- 2.6 - 75.2 +/- 4.7 kcal.kg-0.75.d-1 [P = NS]). During the final 12 h of the fast agreement between the two systems gradually dissipated and correlation was poor (r = 0.375, P < 0.05). The frequency of animal handling necessitated by MIC may have resulted in a stress-induced increase in metabolic work that would mask the animals' adaptive response to starvation. This investigation demonstrates the advantages of the AIC and calls into question the accuracy of manual methods under long-term starvation conditions.

Measurement of urinary urea nitrogen content as an estimate of the amount of total urinary nitrogen loss in dogs in intensive care units

OBJECTIVE

To investigate whether urinary urea nitrogen (UUN) content can be used to accurately estimate total urinary nitrogen content in hospitalized dogs.

DESIGN

Prospective, cohort study.

ANIMALS

24 client-owned dogs admitted to an intensive care unit of a veterinary teaching hospital.

PROCEDURE

Indwelling urinary catheters and closed collection systems were placed for the purpose of monitoring urine output. Urine was collected during a 24-hour period from each dog. For each collection, the total volume was measured. Urine was analyzed for urea nitrogen content at an in-house laboratory, using standard methods for determination of BUN content. Total urinary nitrogen content was determined by another laboratory, using Kjeldahl's method. Correlation between UUN content and total urinary nitrogen content was evaluated by use of linear regression analysis.

RESULTS

Total urinary nitrogen content adjusted for metabolic body weight ranged from 0.21 to 2.21 g/ kg0.75/d (mean +/- SD, 0.81 +/- 0.46 g/kg0.75/d). Adjusted UUN content ranged from 0.05 to 1.50 g/kg0.75/d (0.54 +/- 0.38 g/kg0.75/d). Total urinary nitrogen content was highly correlated with UUN content (R2, 0.88; P < 0.001).

CLINICAL IMPLICATIONS

Measurement of UUN content can be used to estimate total urinary nitrogen content in a clinical setting. Furthermore, critical illness in dogs is associated with substantial catabolism of endogenous proteins.

Idiopathic dilated cardiomyopathy in Dalmatians: nine cases (1990-1995)

OBJECTIVE

To describe the historical, clinical, and echocardiographic findings in Dalmatians with dilated cardiomyopathy (DCM).

DESIGN

Retrospective case series.

SAMPLE POPULATION

9 Dalmatians with a diagnosis of DCM and congestive heart failure (CHF), 9 Doberman Pinschers with DCM and CHF, and 9 dogs of other breeds with DCM and CHF.

PROCEDURE

Disease history; signalment; physical, radiographic, and echocardiographic examination findings; treatment; and outcome from medical records were analyzed.

RESULTS

All Dalmatians were male, with a mean age of 6.8 years. Eight dogs had been fed a commercially available low-protein diet formulated for the prevention of urate uroliths. All dogs had clinical signs consistent with left-sided CHF and had marked left ventricular systolic dysfunction and severe left ventricular dilatation, although arrhythmias were not an important finding in this series of dogs. Median duration of survival was 10 months.

CLINICAL IMPLICATIONS

The DCM syndrome in Dalmatians has some qualities that are distinct from DCM in other breeds of dogs.

Nutritional management of liver disease

The provision of adequate nutrition to the patient with liver disease is a challenge. The practitioner must avoid overwhelming the remaining metabolic capabilities of the damaged organ. The ability of the liver to regenerate and the patient to recover depends on the availability of sufficient nutrients. There is no default diet for the patient with liver disease. Each patient must be evaluated individually, with consideration given to the type and origin of the liver disease, the current extent of hepatic dysfunction, and the patient's previous dietary history. Efforts should be directed at the provision of an energy intake adequate to maintain body weight and a protein intake as close to normal as can be tolerated without precipitating signs of hepatic encephalopathy.

Protection against metastasis of radiation-induced thymic lymphosarcoma and weight loss in C57Bl/6NCr1BR mice by an autoclave-resistant factor present in soybeans

We have investigated the ability of Bowman-Birk inhibitor, a protease (trypsin and chymotrypsin) inhibitor, to protect against radiation-induced thymic lymphosarcoma in C57Bl/6NCr1BR mice. Fifty-five 7-week-old male mice were randomized into 11 groups and gavaged 5 days per week with purified Bowman-Birk inhibitor, Bowman-Birk inhibitor concentrate, and autoclaved Bowman-Birk inhibitor concentrate. Following 7 days of gavage, those mice undergoing total-body or sham total-body irradiation received 1.7 Gy weekly for 4 weeks. At 6 months following the radiation exposure, all mice were sacrificed and examined histopathologically. Samples of Bowman-Birk inhibitor concentrate, purified Bowman-Birk inhibitor, and autoclaved Bowman-Birk inhibitor concentrate were evaluated with thin-layer chromatography. The mice treated with total-body irradiation and autoclaved Bowman-Birk inhibitor had significantly (P < 0.05) fewer deaths, lower average grade of lymphosarcoma, and larger fat stores compared to those treated with total-body irradiation and water gavage. The results for the total-body-irradiated mice receiving Bowman-Birk inhibitor concentrate suggested an effect midway between these two groups. Thin-layer chromatography analysis indicated that sterols and the phospholipids varied in the three different samples in a way that approximately corresponded with the observed effects. We have observed that an autoclave-resistant factor in soybeans is capable of reducing metastasis of radiation-induced lymphosarcoma and weight loss in C57Bl/6NCr1BR mice, presumably by preventing the extension and metastasis of cancer cells. Thus, in addition to the anticarcinogenic Bowman-Birk inhibitor, there appears to be another anticarcinogenic agent in soybeans which is capable of inhibiting the later stages of cancer cell development.