Guava fibre characterization and effects on digestibility, fermentation products, gastrointestinal transit time and palatability of dry diets for dogs.

The use of fruit fibres as a way of reusing industrial waste is attractive and necessary, increasing the efficiency and reducing the environmental impact of the industry. This study characterized guava fibre as a fibrous ingredient and evaluated its effects when included in extruded diets for dogs on nutrient digestibility, faecal traits, fermentation products, gastrointestinal transit time and palatability. Four diets were formulated: CO (control diet, no fibrous ingredients added), GF3 (3% guava fibre), GF6 (6% guava fibre) and GF12 (12% guava fibre). The guava fibre was added to diets in replacement of maize, with small adjustments in the other ingredients to ensure similar contents of protein and fat. The diets were fed to 24 adult Beagle dogs (6 per diet) during 15 days for adaptation followed by 15 days for assessment of digestibility, fermentation end products and gastrointestinal transit time. The palatability of G6 and G12 treatments was evaluated against the CO by the two-pan test. Results were compared by analysis of variance and polynomial contrasts according to the guava fibre inclusion level (p < 0.05). The addition of guava fibre did not change nutrient intake except for the increase on dietary fibre (p < 0.001). Fibre inclusion resulted in a quadratic reduction in total tract apparent digestibility for dry matter, organic matter, crude protein and crude energy (p < 0.001), and on the metabolizable energy content of the foods (p < 0.001). Guava fibre addition did not change the faecal concentration of ammonia, lactic acid, faecal pH and branched chain fatty acids but it decreased acetic and propionic acids concentration (p < 0.01). The inclusion of 12% guava fibre did result in a faster transit time (p = 0.046) compared to the control diet. Guava fibre can be characterized as a novel insoluble non-fermentable fibre source that could be safely used in levels up to 12% in canine extruded diets.

2022 ISFM Consensus Guidelines on Management of the Inappetent Hospitalised Cat.

PRACTICAL RELEVANCE: Inappetence may have many origins and, as a presenting sign or observation in the hospitalised patient, is common in feline practice. Nutritional assessment of every patient is encouraged, to identify the need for, and appropriate type of, intervention indicated. The impact of malnutrition may be significant on the feline patient, perpetuating illness, delaying recovery, slowing wound healing and negatively impacting gut health and immunity. Delayed intervention may result in the cat's deterioration; hence prompt control of contributing factors such as the underlying illness, pain, nausea, ileus and stress is vital to optimise voluntary food intake. Management is multimodal, comprising reduction of stress, medications and assisted nutrition in the form of tube feeding or parenteral nutrition. Use of antiemetic, analgesic, prokinetic and appetite stimulant medications may restore appetite, but placement of feeding tubes should not be delayed. Feeding tubes are generally well tolerated and allow provision of food, water and medication with minimal stress, although clinicians must be aware of complications such as stoma site infections and refeeding syndrome. CLINICAL CHALLENGES: Cats are vulnerable to malnutrition owing to their unique metabolism and specific nutritional requirements. Moreover, their nature as a species means they are susceptible to stress in the hospital environment, which may result in reduced food intake; previous negative experiences may compound the problem. In particular, an inappropriate clinic environment and/or handling may cause or exacerbate inappetence in hospitalised patients, with negative impacts on recovery. Postponing interventions such as feeding tube placement to await improvement, owing to clinician or caregiver apprehension, may hinder recovery and worsen nutritional deficits. EVIDENCE BASE: The 2022 ISFM Consensus Guidelines on Management of the Inappetent Hospitalised Cat have been created by a panel of experts brought together by the International Society of Feline Medicine (ISFM). Information is based on the available literature, expert opinion and the panel members' experience.

Commercial vs Homemade Cat Diets: What you need to know.

PRACTICAL RELEVANCE: A feeding plan recommendation for cats, both healthy and with disease, should include diet choice, amounts to feed and the feeding method. Diet choice can be complex owing to the abundance of products, sometimes with conflicting marketing messages, and the prevalence of information with no scientific basis. It is important to be aware of the specific challenges of both commercial and homemade diets. Moreover, a nutritional assessment is a prerequisite when recommending a diet to ensure that it is safe, appropriate for the cat's life stage and nutritious for long-term feeding. COMMERCIAL VS HOMEMADE DIETS: There are a variety of commercial diets available, allowing considerable customisation. These products are regulated and can be tested to determine nutritional adequacy and safety, although as the industry is partly self-regulated, choice of manufacturer is important. Properly formulated homemade diets can be customised to the patient and are a good option when no commercial product that meets the patient's needs exists. Homemade diets can be an owner preference. A serious limitation is the lack of testing, potentially affecting safety and also resulting in a reliance on database information to determine nutritional adequacy. Generic homemade diet recipes (eg, sourced from the internet) have additional risks of deficiencies and imbalances, and are not recommended. Homemade diets should be devised by a veterinary nutrition specialist with consideration of both patient and owner factors. CLINICAL CHALLENGES: Dietary misinformation, which is all too readily available on the internet, may result in owners making questionable feeding choices for their pets. A homemade diet may be requested by owners based on the perception that there are poor ingredients in commercial foods. The veterinary healthcare team needs to have good evidence-based information to present to owners about diet choice. EVIDENCE BASE: Several decades of research on feline nutrition forms the basis for nutritional requirements and dietary recommendations. There are varying degrees of evidence regarding requirements for each nutrient, and a lack of data on the effects of different types of processing on nutrient needs.

Prevalence, Risk Factors, and Disease Associations of Overweight and Obesity in Dogs that Visited the Veterinary Medical Teaching Hospital at the University of California, Davis from January 2006 to December 2015.

Overweight and obesity contribute to a variety of disease processes and negatively affect quality of life in dogs. A considerable number of epidemiological studies performed in a variety of canine communities revealed varied prevalence, and identified associated risk factors, including neutering. Associations between excessive body weight and certain diseases, including orthopedic diseases, were also reported. However, risk factors and disease associations of overweight and obesity in a larger population of dogs seen in recent years at a single referral veterinary hospital remains undefined. The present study utilized descriptive statistics and logistic regression models to characterize prevalence, risk factors, and disease associations of excessive body weight (both overweight and obesity) in 40,038 dogs that visited the Veterinary Medical Teaching Hospital at the University of California, Davis from January 2006 to December 2015. The overall prevalence of overweight and obesity in 40,038 dogs were 21.1% (n = 8461) and 20.2% (n = 8089) respectively. Dogs that were neutered, female, and considered middle-aged or senior were at increased risk of overweight and obesity. Certain breed types, including Retriever and Spaniel, and certain disease processes, including orthopedic diseases, were also at increased risk of overweight and obesity. Overweight and obesity are prevalent problems, which can benefit from continual education to raise awareness of the scale of the problem to both the veterinary community and the general public. Structured disease surveillance plans monitoring these associated factors also help to guide further research and to better prevent overweight and obesity.

Environmental risk factors in puppies and kittens for developing chronic disorders in adulthood: A call for research on developmental programming.

Many dogs and cats are affected by chronic diseases that significantly impact their health and welfare and relationships with humans. Some of these diseases can be challenging to treat, and a better understanding of early-life risk factors for diseases occurring in adulthood is key to improving preventive veterinary care and husbandry practices. This article reviews early-life risk factors for obesity and chronic enteropathy, and for chronic behavioral problems, which can also be intractable with life-changing consequences. Aspects of early life in puppies and kittens that can impact the risk of adult disorders include maternal nutrition, establishment of the gut microbiome, maternal behavior, weaning, nutrition during growth, growth rate, socialization with conspecifics and humans, rehoming and neutering. Despite evidence in some species that the disorders reviewed here reflect the developmental origins of health and disease (DOHaD), developmental programming has rarely been studied in dogs and cats. Priorities and strategies to increase knowledge of early-life risk factors and DOHaD in dogs and cats are discussed. Critical windows of development are proposed: preconception, gestation, the suckling period, early growth pre-neutering or pre-puberty, and growth post-neutering or post-puberty to adult size, the durations of which depend upon species and breed. Challenges to DOHaD research in these species include a large number of breeds with wide genetic and phenotypic variability, and the existence of many mixed-breed individuals. Moreover, difficulties in conducting prospective lifelong cohort studies are exacerbated by discontinuity in pet husbandry between breeders and subsequent owners, and by the dispersed nature of pet ownership.

Prevalence, risk factors, and disease associations of overweight and obesity in cats that visited the Veterinary Medical Teaching Hospital at the University of California, Davis from January 2006 to December 2015.

Overweight and obesity are commonly diagnosed in domestic cats, and undermine cats' quality of life directly or indirectly via various disease processes known to be associated with overweight and obesity. Epidemiological studies have reported varied overall prevalence among different feline populations, and commonly identified risk factors such as neutering. However, disease associations were not consistently reported. The status of feline overweight and obesity in a referral veterinary teaching hospital in the United States remains undefined as well. The present study used descriptive statistics and logistic regression models to analyze feline medical records obtained at the Veterinary Medical Teaching Hospital at the University of California, Davis from January 2006 to December 2015 and to characterize the prevalence of overweight and obesity, risk factors, and disease associations. In 9,062 feline records analyzed, the overall prevalence of overweight (17.2%; n = 1,560) and obesity (23.8%; n = 2,160) was 41.0%. Neutered, male, and crossbred cats that were in age groups between 3.0 and 14.9 years old and presented with disease processes in orthopedic, dentistry, and urinary categories were positively associated with overweight and obesity. Overweight and obesity are prevalent problems, which can benefit from continual veterinary education emphasizing its importance. Structured disease surveillance plans monitoring these associated factors also help guide further research and ideally can contribute to development of better prevention strategies for overweight and obesity.

Calcium, Phosphorus, and Vitamin D in Dogs and Cats: Beyond the Bones.

Calcium, phosphorus, and vitamin D are nutrients that play a key role in maintaining normal organ, cell, and tissue function. Much is known about their role in bone metabolism, but these nutrients are also important in renal health, urinary tract disease, and multiple other organ systems. It is nutritionally important to meet the physiologic requirements for each of these nutrients, but the interplay between them should also be considered.

Adiponectin as a sepsis biomarker in dogs: Diagnostic and prognostic value.

BACKGROUND: Adiponectin (ADPN) is an adipocytokine with insulin-sensitizing, vascular-protective, and anti-inflammatory properties for which concentration changes occur in response to inflammation. Little is known about the regulation of ADPN and the impact of this adipocytokine in septic dogs. OBJECTIVE: We aimed to assess the diagnostic and prognostic value of ADPN vs other traditional acute-phase proteins (APPs), such as albumin (ALB), haptoglobin (HPT), fibrinogen (FBG), ferritin (FRT), and C-reactive protein (CRP) in dogs with naturally acquired sepsis. METHODS: This prospective observational study included 20 dogs with sepsis, 27 with low-grade systemic inflammation (LGSI), and 18 clinically healthy dogs as controls. For method analyses, plasma samples were obtained from all dogs on admission and then every 24-48 hours until discharge or death in the septic group. RESULTS: Septic dogs had lower ADPN (2.4 ± 0.46 vs 4.5 ± 0.41mg/L, P < .001) dand ALB (17 ± 1 vs 22 ± 0.8g/L, P = .002), and tended to have higher CRP (87 ± 4.8 vs 73 ± 4.1mg/L, P < .079) concentrations than dogs with LGSI on admission. Only ADPN and ALB were able to successfully discriminate animals with LGSI from those presenting with sepsis with areas under the curve (AUCs) for the receiver operating characteristic (ROC) curves of 0.811 and 0.789, respectively. In the septic group, ADPN concentration did not differ between survivors and non-survivors, either on admission or at discharge or death. CONCLUSIONS: Although plasma ADPN can be used as a reliable negative APP in dogs with sepsis, further studies are warranted to confirm the usefulness of this biomarker in terms of disease progression and recovery.

The diagnostic and prognostic value of paraoxonase-1 and butyrylcholinesterase activities compared with acute-phase proteins in septic dogs and stratified by the acute patient physiologic and laboratory evaluation score.

BACKGROUND: Sepsis is a complex syndrome that involves an increased oxidative stress status and dysregulation of cholinergic neurotransmission. Paraoxonase-1 (PON-1) and butyrylcholinesterase (BChE) activities have been identified as significant biomarkers to monitor such disorders in human septic patients. OBJECTIVE: We aimed to determine the diagnostic and prognostic value of PON-1 and BChE vs other traditional acute-phase proteins such as albumin (ALB) and C-reactive protein (CRP) in septic dogs. METHODS: This prospective observational study included 20 dogs with a diagnosis of sepsis, 27 with low-grade systemic inflammation (LGSI), and 10 healthy dogs that served as controls. Plasma samples were obtained from all dogs for analysis on admission, and then every 24-48 hours until discharge or death in the septic group. RESULTS: Dogs with sepsis had lower PON-1 activity compared with dogs in the LGSI group (1.1 ± 0.10 vs 1.6 ± 0.08 U/mL, P = .002), but no differences in BChE activity were detected between the groups. PON-1, ALB, and CRP could successfully discriminate healthy animals from those with sepsis looking at the area under the curve (AUC) of the receiver operator characteristics curves (ROCs), which were 0.828, 0.903 and 1.000, respectively. Finally, although no differences were found among the groups for PON-1 or BChE activity, the nonsurvivor septic dogs had higher CRP (P = .002), lower ALB (P = .025) levels, and tended to have lower PON-1 (P = .082) activities than the survivors at patient death or discharge. CONCLUSION: Septic dogs showed lower plasma PON-1 and higher BChE activities, but only PON-1 activity correlated with disease severity. Further studies are warranted to describe the usefulness of these new biomarkers of sepsis progression and recovery in dogs.

Evaluation of the nutritional adequacy of recipes for home-prepared maintenance diets for cats.

OBJECTIVE: To evaluate home-prepared maintenance diet (HPMD) recipes for cats and compare the nutritional profiles with National Research Council (NRC) recommended allowances (RAs) for essential nutrients for adult cats. DESIGN: Evaluation study. SAMPLE: 114 recipes (obtained from books and online sources) for HPMDs for cats. PROCEDURES: Computer software was used to determine nutrient concentrations of HPMD recipes for comparison with NRC RAs for essential nutrients for adult cats. Effects of recipe authorship (veterinarian vs nonveterinarian) and supplementation on the number of nutrient concentrations below RAs were evaluated. RESULTS: Of the 114 HPMD recipes, 113 contained vague instructions regarding preparation, and 46 did not provide feeding directions. Only 94 recipes provided adequately detailed information for computerized nutritional analysis, although most (93/94) still required assumptions regarding ingredients, preparation, or supplementation. Nonveterinarian-authored recipes and recipes without supplement-type products had more nutrient concentrations below NRC RAs, but no recipe met all RAs. With assumptions, 5 veterinarian-authored recipes met NRC RAs for all assessed nutrients except choline; however, taurine adequacy in 2 of those recipes could not be confirmed. Crude protein concentration was below the RA in 6 of 94 (6.4%) recipes. Nutrients most frequently below RAs included choline, iron, thiamine, zinc, manganese, vitamin E, and copper (in 89.7%, 76.6%, 62.8%, 61.7%, 57.4%, 57.4%, and 45.7% of recipes, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Problems with nutritional adequacy were identified in all evaluated HPMD recipes. Appropriate formulation of HPMDs requires specialized knowledge of nutrition and use of computer software to avoid potentially harmful nutrient deficiencies.

Determination of mammalian DNA in commercial canine diets with uncommon and limited ingredients.

Over-the-counter (OTC) limited ingredient canine diets could be reliable alternatives to veterinary therapeutic formulations for the diagnosis and management of adverse food reaction (AFR). However, the possibility of undeclared ingredients jeopardizes the efficacious use of OTC options for medical purposes. The objective was to determine the presence of undeclared ingredients in OTC canine dry diets marketed as limited or single protein source diets. Twenty-one OTC adult canine diets marketed as limited or single protein source diets were purchased. Multiplex PCR was used to screen for DNA of 10 mammalian species with species-specific primers that anneal to regions of the mitochondrial cytochrome b gene. The presence of DNA from one or more species not declared on the label was identified in all 21 diets: cow (Bos taurus), pig (Sus scrofa), sheep (Ovis sp.), goat (Capra hircus) and bison (Bison bison). Twenty diets were positive for the declared protein source and one diet was negative for the declared species. Cat (Felis catus), dog (Canis sp.), horse (Equus sp.), mouse (Mus musculus) and rat (Rattus norvegicus) DNA was not identified in any samples. The presence of undeclared mammal species in OTC canine dry diets marketed as having limited or single protein source ingredients may complicate AFR diagnosis and treatment. However, PCR can detect a miniscule amount of DNA which might not be clinically significant, because the amount needed to elicit a response is unknown. Quantification of the contamination was not determined in this study, precluding discrimination of intentional adulteration from unavoidable cross-contamination.

Evaluation of the Prevalence and Risk Factors for Undernutrition in Hospitalized Dogs.

Hospitalized dogs are predisposed to undernutrition, which can potentially affect outcome. This study evaluated the prevalence of undernutrition in hospitalized dogs (measured as loss of body condition score, BCS and body weight, BW) and studied the risk factors that affect nutritional status, and outcome (discharge or death). Data was collected prospectively during 9 months from 500 hospitalized dogs with a hospitalization length longer than 24 h in a veterinary teaching hospital in Spain. The BCS and BW changes were modeled using multiple linear regression and outcome was modeled using logistic regression. The risk factors studied were energy intake, hospitalization length, initial BW and BCS, age, sex, severity of clinical signs, department of admission, fasting or nutritional interventions, and the presence of anorexia, vomiting or diarrhea at admission. Most of the dogs (84.0%) consumed less than 25% of their energy requirements and only 3.4% of the dogs met these requirements. The majority of hospitalized dogs maintained their BCS (78.2%) and BW (77%) during hospitalization. Older patients (P = 0.040), higher initial BCS (P < 0.001), and vomiting at admission (P = 0.030) were associated with a decrease of BCS status during hospitalization. BCS was also decreased in patients with low energy intake, particularly in patients with hospitalization length longer than 3 days (P < 0.001). Both longer hospitalization length (P < 0.001) and vomiting at admission (P = 0.004) were also associated with a decrease in BW. Dogs that consumed their theoretical energy requirements [P < 0.001; Odds Ratio (OR) 0.95, 95% CI: 0.92 to 0.98], and had a higher initial BCS (P < 0.001; OR 0.39, 95% CI: 0.22 to 0.63) had a lower odds of dying. Anorexia at admission (P < 0.001; OR 5.67, 95% CI: 2.23 to 15.47) was associated with a higher risk of death. The results from this study support the finding that undernutrition is relatively common during hospitalization, with age, hospitalization length, decreased energy intake, and vomiting at admission as risk factors for undernutrition. Furthermore, an association was found between inadequate energy intake and death.

Weight loss improves arterial blood gases and respiratory parameters in obese dogs.

Canine obesity is a common medical disorder and a known risk factor for associated diseases; it can seriously influence various physiological functions, thereby limiting the longevity of the animal. In this study, we evaluated potential respiratory alterations in obese dogs before and after being subjected to caloric restriction to decrease their body weight by 20%, and compared those dogs with control dogs with ideal body condition score. The animals were divided into three experimental groups: GI (obese dogs; n = 11); GII (obese dogs after weight loss, same animals as in GI); GIII (control dogs; n = 11). We evaluated lung function by spirometry and arterial blood gases. Statistical analysis included paired or non-paired Student's t test. Compared with dogs within an ideal body condition score (GIII), obese dogs (GI) had a low arterial partial pressure of oxygen (p < 0.05); decreased tidal volume (p < 0.005), inspiratory time and expiratory time (p < 0.05); and an increased respiratory rate (p < 0.005). After losing weight (GII), no differences with control dogs (GIII) were verified. The results suggested that obese dogs have an improvement in respiratory function with weight loss, but further investigations in a larger group of dogs are advised to confirm these findings.

Effect of enzyme supplements on macronutrient digestibility by healthy adult dogs.

Some enzyme supplement products claim benefits for healthy dogs to compensate for alleged suboptimal production of endogenous enzymes and the loss of enzymes in commercial pet foods secondary to processing. The objective of the current study was to determine macronutrient and energy digestibility by healthy adult dogs fed a commercial maintenance diet with or without supplementation with plant- and animal-origin enzyme products at the dosage recommended by their respective manufacturers. A group of fourteen healthy neutered adult Beagle dogs (average age 8 years) was divided into two equal groups and fed the basal diet alone and then with either the plant- or animal-origin enzyme supplement in three consecutive 10-d periods; the treatment groups received the opposite enzyme supplement in the third period. Digestibility in each period was performed by the total faecal collection method. Serum trypsin-like immunoreactivity (TLI) was measured at the end of each trial. Data were analysed by repeated measures and the α level of significance was set at 0·05. There were no differences in energy and nutrient digestibility between enzyme treatments. When comparing basal with enzyme supplementation, fat digestibility was higher for the basal diet compared with the animal-origin enzyme treatment, which could be a period effect and was not biologically significant (94·7 v. 93·5 %). Serum TLI was not affected by supplementation with either enzyme product. Exogenous enzyme supplementation did not significantly increase digestibility of a typical commercial dry diet in healthy adult dogs and routine use of such products is not recommended.

Prevalence of and risk factors for intraoperative gastroesophageal reflux and postanesthetic vomiting and diarrhea in dogs undergoing general anesthesia.

OBJECTIVE: To determine the prevalence of intraoperative gastroesophageal reflux (GER) and postanesthetic vomiting and diarrhea, and to evaluate risk factors associated with these gastrointestinal disorders (GID) in dogs undergoing general anesthesia. DESIGN: Prospective observational study. SETTING: University teaching hospital. ANIMALS: Two hundred thirty-seven client-owned dogs undergoing general inhalant anesthesia for diagnostic or surgical purposes. INTERVENTIONS: None MEASUREMENTS AND MAIN RESULTS: Patient, surgical, and anesthetic variables, and postanesthetic treatments administered in the immediate postanesthesia period were evaluated in relation to GID using univariate and multivariate logistic regression analysis (P < 0.05). Seventy-nine of the 237 (33.4%) dogs developed GID during the perianesthetic period. The prevalences of GER, vomiting, and diarrhea were 17.3%, 5.5%, and 10.5%, respectively. Intraabdominal surgery (P = 0.016; odds ratio [OR] 2.82, 95% confidence interval [CI]: 1.21-6.62), changes in body position (P = 0.003; OR 3.17, 95% CI: 1.47-6.85), and length of anesthesia (P = 0.052; OR 1.006, 95% CI: 1.000-1.013) were associated with GER. Changes in the ventilation mode during surgery (P = 0.011; OR 6.54, 95% CI: 1.8-23.8), length of anesthesia (P = 0.024; OR 1.001, 95% CI: 1.001-1.020), and rescue synthetic colloid support due to hypotension (P = 0.005; OR 6.9, 95% CI: 1.82-26.3) were positively associated with postanesthetic vomiting. On the contrary, dogs that received acepromazine as premedication were significantly less likely (P < 0.019; OR 12.3, 95% CI: 1.52-100) to vomit. Finally, length of anesthesia, changes in body position, changes in ventilation mode, or hypoxemia during the procedure tended to increase the risk (univariate model) of diarrhea during the recovery phase. CONCLUSIONS: GID are common in dogs undergoing general anesthesia. Duration and characteristics of the procedure, anesthetic management, and changes in certain patient variables are significant risk factors for the presence of GID in the perioperative period.

Scope of the Problem and Perception by Owners and Veterinarians.

Obesity is a common disease of modern dogs and cats. Dog and cat owners often do not realize their animal is affected. Some pet owners are skeptical of the diagnosis or rationalize the overweight condition of their pets. Animal-related factors associated with obesity in dogs and cats include breed, neuter status, age, and gender, whereas owner-related factors include diet choice, feeding method, and provision of exercise. Owner characteristics, such as age and income, are also potential risk factors for pet obesity. Identifying such risk factors for both animals and owners may help provide targets for prevention or interventional tools.

Macronutrients in feline health.

Dietary macronutrients include protein, fat, and carbohydrates. Current nutritional recommendations establish minimums but not maximums for protein and fat but not for carbohydrates; thus, commercial feline maintenance diets have a wide range of macronutrient distribution depending on manufacturer, ingredients, and processing. There is growing interest and discussion, however, in defining the ideal macronutrient composition of feline diets to maximize longevity and health. Current recommendations should be tailored to each patient based on age, body condition, presence of muscle mass atrophy, and the presence of disease.

Preliminary study: voluntary food intake in dogs during tryptophan supplementation.

Tryptophan, a precursor of important molecules such as serotonin, melatonin and niacin, is an essential amino acid for dogs. In pigs, tryptophan supplementation has been shown to induce a significant increase in food intake. The aim of the present study was to assess whether long-term tryptophan supplementation increases voluntary food intake in dogs and to observe whether this was accompanied by a change in serum ghrelin. In the present study, sixteen adult Beagle dogs were used, with four male and four female dogs fed diets supplemented with tryptophan (1 g/dog per d) during 81 d (Trp) and four male and four female dogs that were not supplemented (control). A voluntary food intake test was performed during 5 d following the supplementation period. The Trp group tended to show a higher food intake during the voluntary food intake test (58.0 (SE 5.37) v. 77.5 (SE 3.65) g/kg metabolic weight per d; P = 0.074). No significant differences were found for serum ghrelin concentrations.

Effect of water content in a canned food on voluntary food intake and body weight in cats.

OBJECTIVE: To determine whether water content in a canned food diet induces decreases in voluntary energy intake (EI) or body weight (BW) in cats fed ad libitum. ANIMALS: 16 sexually intact male domestic shorthair cats. PROCEDURES: Maintenance EI was determined for 2 months in 10 weight-stable cats consuming a control diet (typical colony diet). Cats were allocated into 2 groups of equal BW and fed a canned diet (with-water [WW] diet) or a freeze-dried version of the canned diet (low-water [LW] diet) twice daily. Diets were identical in nutrient profile on a dry-matter basis. Each dietary treatment period of the crossover experiment lasted 3 weeks, with a 3-week washout period between diets. Body composition measurements were determined by use of deuterium oxide at the end of each dietary treatment. Daily food intake was measured for determination of dry-matter intake and EI. Six other cats were used in preference tests for the 3 diets. RESULTS: EI was significantly decreased for the WW diet (mean ± SD, 1,053.0 ± 274.9 kJ/d), compared with EI for the LW diet (1,413.8 ± 345.8 kJ/d). Cats had a significant decrease in BW during consumption of the WW diet. Body composition was unaltered by diet. In short-term preference tests, cats ate significantly more of the WW than the LW diet. CONCLUSIONS AND CLINICAL RELEVANCE: Bulk water in the WW diet stimulated decreases in EI and BW in cats. The impact of water content on energy density and food consumption may help promote weight loss in cats.