Energy requirements of adult dogs: a meta-analysis

Accuracy of Predictive Equations for Metabolizable Energy Compared to Energy Content of Foods for Dogs and Cats Estimated by In Vivo Methods in Brazil

In small animal nutrition, the caloric content of a diet is expressed as metabolizable energy (ME). The gold standard method for determining this variable is through feeding trials with the target species. However, the high cost and intricacy of this assay lead to the use of indirect estimation methods. The aim of this study was to analyze the main equations employed for estimating ME and compare them with the results of in vivo tests. In total, 451 pet food products in Brazil were evaluated. The ME values were determined via the bromatological values available on labels. The data were analyzed using SAS, and Student's t test was used with a significance of 5%. For all predictive equations, there was a non-conformity between their results and those obtained by in vivo methods. Thus, the prediction equations are only accurate when the exact values of food composition are used, which is hardly applicable since veterinarians and animal owners only have access to the information provided on the labels. Nonetheless, the Atwater system equation proved to be the most reliable for estimating ME, showing the smallest disparity among the evaluated methods. The overall differences between in vivo results and ME estimation with the Atwater system amounted to 3.59% for dry cat foods and -1.94% for dry dog foods. Moreover, although it was also the most accurate for wet foods, the differences were substantially greater (11.99% for cat foods and 8.25% for dog foods). These findings highlight the need for further research to refine ME estimation, which could contribute to improved pet food formulation and help reduce cases of malnutrition in dogs and cats.

Overweight and obese body condition in ∼4.9 million dogs and ∼1.3 million cats seen at primary practices across the USA: Prevalences by life stage from early growth to senior

Adult dogs and cats in overweight or obese condition are common, but prevalence data for different life stages, especially growth, are limited, and may help inform when preventative measures may be most effective. In this retrospective observational study, prevalences of overweight and obese condition were determined from the electronic medical records of dogs and cats of all life stages visiting Banfield Pet Hospital in the USA between 2020 and 2023. Animals were identified either by body condition score (BCS; overweight 6-7; obese 8-9) or from a clinical diagnosis of overweight condition or obesity when recorded. Life stages (early growth, late growth, young adult, adult, mature, and senior) were defined by age range, adjusted for species and breed size in dogs. Individuals could only be included once within each life stage, with the maximum BCS used. Prevalence was determined for the 4-year period and for each calendar year. The evolution of BCS was also assessed for animals with multiple records. In total, 4933,916 unique dogs and 1341,118 unique cats were included. In dogs, prevalences of overweight or obese condition were: 0.9 % and < 0.0 % (early growth), 9.5 % and 0.3 % (late growth), 24.4 % and 1.9 % (young adult); 44.5 % and 8.4 % (adult), 50.1 % and 12.6 % (mature); 46.4 % and 11.3 % (senior). In cats, prevalences of overweight or obese condition were: 0.8 % and < 0.0 % (early growth); 10.7 % and 0.4 % (late growth); 36.2 % and 3.6 % (young adult); 47.2 % and 13.9 % (adult); 44.8 % and 21.7 % (mature); and 32.0 % and 12.6 % (senior). From 2020-2021 and 2021-2022 prevalences of overweight and obese condition in dogs and overweight condition in cats increased in most life stages. The prevalence of overweight condition in dogs and obese condition in cats and dogs significantly decreased between 2022 and 2023 for some life stages. The odds ratio of an overweight or obese condition in adulthood was 1.85 (95 % confidence interval [CI]: 1.81, 1.86); P ≤ 0.001) for dogs and 1.52 (95 % CI: 1.48, 1.56; P ≤ 0.001) for cats where an overweight or obese condition was recorded during growth. In conclusion, both overweight and obese condition are prevalent throughout adult life, peaking during the mature life stage in dogs and cats, with overweight or obese condition during growth persisting into adulthood in most affected animals. Veterinarian-led prevention strategies are recommended from growth onwards, including the use of growth standard charts.

Nutrient Digestive Bypass: Determinants and Associations with Stool Quality in Cats and Dogs

The effect of digestive bypass macronutrients and age on stool quality (moisture and firmness) in dogs and cats is not well understood. Data were analyzed from digestibility tests (n = 2020, 361 dogs and 536 cats) including dry and wet product types. Both food and feces were measured for moisture and nutrients according to standard protocols; stool firmness was graded. Linear mixed modeling was used to evaluate the associations between nutrient bypass, age and stool quality. Bypass protein increased stool moisture (dog, cat p < 0.0001) and decreased firmness (dog p = 0.01, cat p < 0.0001), while bypass fiber decreased stool moisture and increased firmness (dog, cat p < 0.0001 for both). Both species manifested a negative quadratic effect of advanced age on stool firmness (dog p < 0.0001 and cat p = 0.02). However, the association of advanced age (quadratic effect) with metabolizable energy required to maintain body weight was different between species; dogs had a positive association (p = 0.028), while it was negative for cats (p < 0.0001). Taken together, these data may aid in the development of food formulations for companion animals, which can better meet changing nutritional needs across life stages.

Retrospective investigation of the energy requirements for weight loss and weight maintenance after weight loss programme in obese dogs

Obesity is a highly prevalent disease in dogs and is characterized by the excessive accumulation of adipose tissue that results in metabolic changes. Its treatment is based on a negative energy balance focusing on energy restriction. However, there are few studies in dogs that assessed the energy intake needed for adequate weight loss and to weight maintenance afterward. The aim of this study was to evaluate data about the treatment of canine obesity, with emphasis on energy restriction to induce weight loss and to maintain body weight (BW) and ideal body condition after weight loss. This was a retrospective study in which records of obese dogs from a veterinary teaching hospital were assessed between 2014 and 2020. Sixteen dogs were considered in the study according to inclusion and exclusion criteria and 10 of these participated in the maintenance phase after weight loss. The animals lost a mean of 23.2% their initial weight in a mean of 422 days. The mean weekly weight loss rate was 0.58% of BW, and the mean daily energy intake for weight loss was 59 kcal/kg current BW0.75. When the target BW was considered, which was defined as the current weight minus 10% for every point in the body condition score scale above 5, the mean energy for weight loss was 71 kcal/kg target BW0.75. In the maintenance phase, the animals were assessed for a mean of 134 days. The mean energy intake to maintenance BW was 70 kcal/kg BW0.75. The lower energy requirement of obese dogs during and after weight loss can work as an alert for the formulations of therapeutic weight loss diets to contain a high nutrient density focusing on the wellbeing, health, and quality of life of obese dogs, not just for the weight loss phase, but a diet for the weight maintenance phase.

The relative benefits for environmental sustainability of vegan diets for dogs, cats and people

Environmental impacts of the livestock sector are proportional to consumption levels. To assess the relative consumption of livestock animals within the diets of dogs, cats and people, this study examined their dietary energy needs within the US in 2020, and globally in 2018. Also studied were US pet food ingredients, and environmental sustainability indicators for plant- and animal-based foods consumed globally. Relative consumptions of average livestock animals were: US: dogs- 17.7%, cats- 2.3%, humans- 80.0%; and globally: dogs- 7.7%, cats- 1.2%, humans- 91.1%. Full transition to nutritionally-sound vegan diets would spare from slaughter the following numbers of terrestrial livestock animals annually (billions): US: dogs- 1.7, cats- 0.2, humans- 7.8, and globally: dogs- 6.0, cats- 0.9, humans- 71.3, as well as billions of aquatic animals in all dietary groups. Very large impact reductions were also associated with land and water use, emissions of greenhouse gases (GHGs), acidifying and eutrophifying gases, and biocide use, in all dietary groups. If implemented globally, nutritionally-sound vegan diets would free up land larger than the following nations: dogs-Saudi Arabia or Mexico, cats-Japan or Germany, humans-Russia-the world's largest country-combined with India. Such diets would save freshwater volumes greater than all renewable freshwater in the following nations: dogs-Denmark, cats-Jordan, humans-Cuba. Such diets would reduce GHGs by amounts greater than all GHG emissions from following nations: dogs-South Africa or the UK, cats-Israel or New Zealand, humans-India or the entire EU. The numbers of additional people who could be fed using food energy savings associated with vegan diets exceeded the 2018 human populations of the following nations: dogs-the entire European Union, cats-France or the UK, humans-every single nation or collective region on Earth, as defined by the World Bank. All of these estimates are conservative.

The 13C-bicarbonate technique as a tool for measurement of energy expenditure in overweight dogs undergoing body weight reduction and the effect of different dietary composition

Changes in body size and composition, i.e., body weight (BW) gain or loss, affect the daily energy expenditure (EE). To ensure an appropriate BW reduction and to find an efficient strategy to reduce and maintain a target BW, regular evaluations and adjustments of energy allowance are important. This study aimed to provide a detailed knowledge about the possible changes in resting EE using the oral 13C-bicarbonate technique (o13CBT) as a research tool in 16 overweight pet dogs undergoing BW reduction. Dietary composition (i.e., in % of dry matter [DM] being a high protein [33.3], low fat [9.6], and high crude fiber [18.0] diet [LFHFibre], and a high protein [37.9], high fat [52.0], carbohydrate-free diet [HFat]) during 16 wk of energy restriction were evaluated regarding effects on resting EE, rate of BW reduction, body composition, and plasma concentrations of metabolic hormones involved in energy metabolism and appetite regulation. The mean BW loss was higher (P < 0.05) for the dogs fed the LFHFibre diet (1.1%/wk) than that for dogs fed the HFat diet (0.8%/wk), but the total BW reduction of 14.6% and 12.0% of initial BW did not differ significantly (P > 0.05). Resting EE was lower (P < 0.02) after the BW reduction; 414 kJ (99 kcal)/kg BW0.75/d at the start (week 0) and 326 kJ (78 kcal)/kg BW0.75/d at the end (week 16) of the study. The BW reduction in both groups (P > 0.05) consisted of both fat mass (FM) and fat-free mass (FFM). Energy expenditure, calculated in relation to amount of FFM, was not significantly (P > 0.05) affected by BW reduction. Dietary composition did not significantly affect (P > 0.05) plasma concentrations of insulin, leptin, and ghrelin, and no effect (P > 0.05) of BW reduction was observed on hormone concentrations. In conclusion, the o13CBT proved to be a useful research method for studying short-term EE in overweight dogs. Even though all dogs lost BW, most dogs were still overweight at the end of the study. Due to a high individual variation among dogs, a longer experimental period with a larger sample size would be desirable.

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.

Physical activity and sport-specific training patterns in Swedish sporting and working trial dogs-A questionnaire survey

OBJECTIVE

To explore physical activity patterns, including conditioning exercise and sport-specific training, and management routines utilized by handlers of Swedish sporting and working dogs participating in agility, obedience, rally obedience and working trial disciplines.

PROCEDURES

Dog handlers provided information on competition-level dogs through an internet-based cross-sectional and descriptive survey on physical activity, sport-specific training and management. Results are reported overall and stratified by participation in specific disciplines.

RESULTS

We received 1615 replies to the questionnaire. After data cleaning, 1582 dogs (98%) remained for the analysis. Of these, 430 participated in agility, 790 in obedience, 596 in rally obedience, and 847 dogs had competed in a working trial, i.e., messenger, protection, search or tracking. Number of disciplines performed by each dog varied between one and five. Most common was participation in one (n = 767, 48%) or two (n = 541, 34%) disciplines. Out of the dogs competing in one discipline, 38% (n = 294) were considered to be specialized as they actively trained only that discipline for ≥10 months per year. The vast majority of the dogs (n = 1129, 71%) received more than 1 h of daily physical activity, e.g., walks, and only n = 51 (3%) were never exercised off-leash. Preferred self-selected gait was trot (n = 907, 57%) and gallop (n = 499, 32%). A fifth (n = 319, 20%) never played with other dogs. The majority (n = 1328, 84%) received more than 1 h of vigorous physical conditioning exercise per week. Almost three quarters (n = 1119, 71%) participated in physical conditioning exercise. Two thirds (n = 953, 60%) participated in at least 3 h of sport-specific training per week and only a very small portion (n = 35, 2%) trained their specific discipline less than once per week. Median total work load, i.e., all daily physical activity, vigorous physical conditioning exercise and sport-specific training, was 16.5 h per week.

CONCLUSION AND CLINICAL RELEVANCE

We observe physical activity at moderate to high durations and moderate to vigorous intensities among Swedish sporting and working trial dogs. Most dogs received physical conditioning exercise, but not all dogs were warmed up before training and competition. Our study provides veterinary professionals and dog trainers with valuable insights on the physical exposures and management routines of sporting and working trial dogs.

Do intense weather events influence dogs' and cats' behavior? Analysis of owner reported data in Italy

Climate change is a threat to global health and can affect both veterinary and human health. Intense weather events, including sudden and violent thunderstorms or periods of extreme heat, are predicted to rise in frequency and severity and this could lead owners to significantly change their habits and schedules based on the weather, could modify human management and could aggravate pre-existing behavioral problems in pets. The aims of the present study were to identify and quantify possible weather events impact on management, behavior, and behavioral problems of Italian dogs and cats, based on previous owners' experiences with their animals. Two questionnaires were prepared, one for dogs and one for cats, investigating owners' perceptions of the impact of weather events on their pets' behavior. A number of 392 dogs and 426 cats' owners answered the questionnaire. Our study showed that many behaviors in both species were equally modified by environmental temperature. Play and activity increased with cold weather and decreased with heat, and sleep increased with drops in temperature and with hot weather. In particular, the increase in activity in correspondence with the thermic drop was more significant in males, while the increase in playing behavior was statistically greater in the Sheepdogs and Cattle dogs –group1. Weather events did not affect aggressive and house soiling behaviors in both dogs and cats, but weather events, including wild thunderstorms, torrential rains influenced the pets' behavior. Understanding how pets modify their behaviors based on a different owners' schedule and to weather events can help to refine prevention strategies through societal changes and owner education.

Less is more? Ultra-low carbohydrate diet and working dogs' performance

New Zealand farm working dogs are supreme athletes that are crucial to agriculture in the region. The effects that low or high dietary carbohydrate (CHO) content might have on their interstitial glucose (IG) and activity during work are unknown. The goals of the study were to determine if the concentration of IG and delta-g (a measurement of activity) will be lower in dogs fed an ultra-low CHO high fat diet in comparison to dogs fed a high CHO low fat diet, and to determine if low concentrations of IG are followed by reduced physical activity. We hypothesized that feeding working farm dogs an ultra-low CHO diet would reduce their IG concentrations which in turn would reduce physical activity during work. We prospectively recruited 22 farm dogs from four farms. At each farm, dogs were randomized to one of two diets and had a month of dietary acclimation to their allocated diet. The macronutrient proportions as a percentage of metabolizable energy (%ME) for the high CHO low fat diet (Diet 1) were 23% protein, 25% fat, and 52% CHO, and for the ultra-low CHO high fat diet (Diet 2) 37% protein, 63% fat, and 1% CHO. Following the acclimation period, we continuously monitored IG concentrations with flash glucose monitoring devices, and delta-g using triaxial accelerometers for 96 h. Dogs fed Diet 2 had a lower area under the curve (±SE) for IG (AUC _{Diet 2} = 497 ± 4 mmol/L/96h, AUC _{Diet 1} = 590 ± 3 mmol/L/96h; P = 0.002) but a higher area under the curve (±SE) for delta-g (AUC _{Diet 2} = 104,122 ± 6,045 delta-g/96h, AUC _{Diet 1} = 80,904 ± 4,950 delta-g/96h; P< 0.001). Interstitial glucose concentrations increased as the activity level increased (P < 0.001) and were lower for Diet 2 within each activity level (P < 0.001). The overall incidence of low IG readings (< 3.5 mmol/L) was 119/3810 (3.12%), of which 110 (92.4%) readings occurred in the Diet 2 group (P = 0.001). In the Diet 2 group, 99/110 (90%) of the low IG events occurred during the resting period (19:00–06:00). We conclude that feeding Diet 2 (ultra-low CHO high fat diet) to working farm dogs was associated with increased delta-g despite decreased IG concentrations. Interstitial glucose concentrations were positively associated with dogs’ activity levels independent of diet. Lastly, events of low IG occurred at a low incidence and were predominantly seen between 19:00–06:00 in dogs fed the ultra-low CHO high fat diet.

Age-related digestibility of nutrients depending on the moisture content in aged dogs

Digestibility of pet food can affect the health of dog, especially of aged animals. To maintain the health of dogs in an overall good status it is necessary to provide nutritionally balanced food. For example, the digestibility of dogs was known to be decreased along aging. In addition, losing teethes is an often event in aged dogs that could induce a problem to eat a large size dry pet food. Nonetheless, few detailed information is available on the most suited feeding for aged dogs. As part of the nutritional study of food for aged dogs, in this study, we tested whether food type impacts on digestibility on adult versus senior dogs. The methodology to measure the digestibility of nutrients was chosen the index method using chromium oxide. Dogs were fed the same commercial dry or wet diets, which were supplemented with 0.5% chromium oxide. The wet food was prepared by adding twice volume of water in the dry food prior to incubated overnight (14-16 hours) at room temperature. After five days, their feces were collected up to a total weight of > 200 g which was the amount to analyze undigested nutrients in feces as 3 repeats. In the apparent total tract digestibility analysis of the experimental breed, no difference in the digestibility of crude protein, crude fat, crude fiber, ash, and energy was observed regarding the moisture content of the food. Noteworthy, the digestibility of nitrogen free extract was significantly increased in senior dogs fed dry dog food compared with adult dogs fed the same diet, whereas no difference was observed between senior and adult dogs fed wet food. The small breed dogs showed similar results to the experimental breed dogs. However, the digestibility of crude fat was additionally affected by age and food type unlike the experimental breed dogs. This finding suggests that the food moisture content affects the digestibility of nutrients in dogs with aging. Hence, it may be helpful to determine the nutrient contents in foods for senior dogs depending on the food type.

Effect of crude fiber and total dietary fiber on the calculated nitrogen-free extract and metabolizable energy content of various dog foods fed to client-owned dogs with osteoarthritis

OBJECTIVE

To compare measurements of crude fiber (CF) and total dietary fiber (TDF) for various dog foods and their effect on the calculated nitrogen-free extract and metabolizable energy (ME) content, and to compare label-guaranteed and laboratory-analyzed macronutrient values.

SAMPLES

51 dog foods fed to client-owned dogs with osteoarthritis.

PROCEDURES

Foods were analyzed for dry matter, ash, crude protein, acid-hydrolyzed fat, CF, and TDF. Metabolizable energy was calculated by use of a formula with modified Atwater factors and formulas recommended by the National Research Council that included both CF and TDF values. Linear regression analysis was performed to determine the correlation between CF and TDF values.

RESULTS

Only a few foods failed to conform to the guaranteed analysis for all macronutrients except for CF, in which approximately 40% of the foods exceeded the guaranteed maximum values. The CF and TDF values were moderately correlated (r = 0.843). Correlations among CF- and TDF-based ME estimations were moderate with use of the modified Atwater formula and strong with use of the National Research Council formulas (r = 0.86 and r = 0.91, respectively).

CONCLUSIONS AND CLINICAL RELEVANCE

Values for CF were the most variable of the macronutrients of the evaluated dog foods and results suggested that CF is an incomplete and inaccurate measurement of dietary fiber content and, thus, its inaccuracy may lead to inaccurate and variable ME values.

Safety of Dietary Camelina Oil Supplementation in Healthy, Adult Dogs

This study aimed to determine whether camelina oil is safe for use in canine diets, using canola oil and flax oil as controls, as they are similar and generally regarded as safe (GRAS) for canine diets. A total of thirty privately-owned adult dogs of various breeds (17 females; 13 males), with an average age of 7.2 ± 3.1 years (mean ± SD) and a body weight (BW) of 27.4 ± 14.0 kg were used. After a 4-week wash-in period using sunflower oil and kibble, the dogs were blocked by breed, age, and size and were randomly allocated to one of three treatment oils (camelina (CAM), flax (FLX), or canola (OLA)) at a level of 8.2 g oil/100 g total dietary intake. Body condition score (BCS), BW, food intake (FI), and hematological and select biochemical parameters were measured at various timepoints over a 16-week feeding period. All of the data were analyzed with ANOVA using the PROC GLIMMIX of SAS. No biologically significant differences were seen between the treatment groups in terms of BW, BCS, FI, and hematological and biochemical results. Statistically significant differences noted among some serum biochemical results were considered small and were due to normal biological variation. These results support the conclusion that camelina oil is safe for use in canine nutrition.

2021 AAHA Nutrition and Weight Management Guidelines for Dogs and Cats

The guidelines discuss the components of a systematic approach to nutritional management of dogs and cats. A nutritional assessment, including a body condition score and muscle condition score, is a screening evaluation that should ideally be performed at every examination. Individualized nutritional recommendations, based on the nutritional assessment, should be designed to achieve and maintain an appropriate body weight and meet nutritional requirements. Communicating nutritional recommendations to clients is a challenging aspect of nutritional management because pet owners may interpret the practice team's guidance as advocacy for a particular pet food brand or a judgment of the client's ability to properly care for the pet or of the owner's own nutritional status. The guidelines discuss approaches for effective, nonjudgmental communication of dietary recommendations to clients and strategies to increase acceptance of and adherence to veterinary nutrition recommendations. Other pet nutrition topics of current interest include recommendations for particular pet life stages, breeds, and disease conditions; risk factors for nutritional deficiencies and obesity; and considerations for home-prepared diets.

Frequency, breed predisposition and demographic risk factors for overweight status in dogs in the UK

OBJECTIVES

To evaluate the prevalence and risk factors for overweight status in dogs under primary veterinary care in the UK.

MATERIALS AND METHODS

A retrospective study design was used to estimate the 1-year (2016) period prevalence of overweight status. The clinical records were randomly ordered and manually validated for dogs with overweight status during 2016. Univariable and multivariable logistic regression modelling were used to evaluate associations between risk factors (breed, brachycephalic status, adult bodyweight, bodyweight relative to breed-sex mean, age, sex-neuter and insurance) and overweight status.

RESULTS

There were 1580 of 22,333 dogs identified as overweight during 2016. The estimated 1-year period prevalence for overweight status recorded in dogs under veterinary care was 7.1% (95% confidence interval 6.7-7.4). After accounting for confounding factors, eight breeds showed increased odds of overweight status compared with crossbred dogs. The breeds with the highest odds included the Pug (OR 3.12, 95% confidence interval 2.31 to 4.20), Beagle (OR 2.67, 1.75 to 4.08), Golden Retriever (OR 2.58, 1.79 to 3.74) and English Springer Spaniel (OR 1.98, 1.31 to 2.98). Being neutered, middle-aged and insured were additionally associated with overweight status.

CLINICAL SIGNIFICANCE

Targeted overweight prevention strategies should be prioritised for predisposed breeds, such as Pugs and Beagles. The findings additionally raise questions about further preventative efforts following neutering. The prevalence estimate suggests veterinary professionals are underreporting overweight status and therefore could be missing key welfare opportunities.

Commercial diet recommendations and follow-up for a large breed puppy with an intrahepatic portosystemic shunt

A 6-month-old, intact male Great Dane dog fed a veterinary therapeutic liver diet was evaluated after diagnosis of an intrahepatic portosystemic shunt and hind limb angular limb deformity to determine appropriateness of diet. Evaluation of the current diet revealed it to be inadequate to meet the nutrient requirements of a large breed puppy. The dog clinically improved following a change in diet. There was no longer any angular limb deformity and no reported neurological signs. This report highlights the importance of appropriate feeding management during growth and demonstrates that although veterinary therapeutic diets may appear to be an appropriate choice initially, they may not be ideal for growing puppies as a long-term feeding option. Key clinical message: An individual approach is key for nutritional management of complicated canine veterinary medical cases and includes consideration of the patient's life stage requirements when modifying nutrient intake to manage clinical disease.

Estimation of energy expenditure using the oral 13 C-bicarbonate technique in privately owned adult and senior dogs of three different body sizes

Knowledge about energy requirements (ER) of dogs is important in order to provide dogs with an appropriate energy supply. In this study, the oral ¹³ C-bicarbonate technique (o¹³ CBT) was used to estimate energy expenditure (EE) in 50 privately owned dogs of different body sizes (small: Danish-Swedish Farmdog (DSF, n = 16), medium: Beagle (n = 15), large: Labrador Retriever (n = 19)), of different ages (adult: 2-7 years (n = 33), senior: ≥8 years (n = 17)). The aim was to evaluate the feasibility of the method in the field and to get more information about ER of dogs. All dogs were measured twice, on two separate days under standardized, resting conditions. The dogs were fasted overnight prior to measurements, which were carried out in home environment. Only measurements of dogs resting calmly were included in the statistical analyses. No significant difference (p > 0.05) in EE was found between days of measurements. The EE measured in Labrador Retrievers (405 kJ (97 kcal)/kg BW^0.75 /day) was significantly lower (p < 0.001) than of Beagles (530 kJ (127 kcal)/kg BW^0.75 /day) and DSF (497 kJ (119 kcal)/kg BW^0.75 /day), the difference between Beagles and DSF being non-significant. Senior dogs had significantly lower (p < 0.001) EE values than adult dogs with least square means (LSM) of 441 kJ (105 kcal)/kg BW^0.75 /day and 513 kJ (123 kcal)/kg BW^0.75 /day respectively. Analysed within breeds, EE of senior Labrador Retrievers (370 kJ (88 kcal)/kg BW^0.75 /day)) was significantly lower (p < 0.01) than adults (439 kJ (105 kcal)/kg BW^0.75 /day), as well as in DSF (453 kJ (108 kcal)/kg BW^0.75 /day and 541 kJ (129 kcal)/kg BW^0.75 /day for senior and adult dogs respectively). However, the EE was not significantly different (p > 0.05) between adult (548 kJ (131 kcal)/kg BW^0.75 /day) and senior (499 kJ (119 kcal)/kg BW^0.75 /day) Beagles. This study suggests that when measured under standardized resting conditions, the o¹³ CBT can provide reliable results of EE and be a helpful tool to get more knowledge about ER of dogs of different sizes, breeds and ages.

Soybean meal and poultry offal meal effects on digestibility of adult dogs diets: Systematic review

Soybean meal and poultry offal meal are protein ingredients commonly used in the formulation of commercial diets for dogs. However, there remains great variability in the data on the digestibility of each protein source. This systematic review study aimed to examine the intake, apparent nutrient digestibility coefficients and fecal output of protein sources (soybean meal and poultry offal meal) in adult dog food as reported in published studies. The article search was conducted in August 2018 in the PUBMED, SciELO, Science Direct and AGRIS indexing databases. The literature search was performed using "digestibility", "source protein" and "dog" as the main key terms combined with sub-terms to broaden the scope of the search. Criteria were defined for readability, exclusion and inclusion of articles. Results were organized in groups according to the search in the indexing databases, totaling 1,414 articles. After the works were selected following the inclusion criteria, 17 articles were evaluated in this review. According to most studies, plant-based ingredients have a less variable nutritional composition than animal-derived ingredients and poultry offal meal increases the digestibility coefficients of nutrients and energy and reduces fecal dry matter production. Factors inherent to raw-material origin, ingredient and food processing, as well as the high heterogeneity of the methodologies evaluated in the studies are directly related to the obtained results. To ensure a more accurate evaluation of the quality and of effects on the digestibility of protein sources, we recommended that articles include ingredient processing data and that the variables be evaluated under standardized study conditions.

Energy Requirements for Growth in the Norfolk Terrier

An appropriate energy intake for healthy growth can reduce the risk of obesity and co-morbidities, such as orthopaedic diseases. The 2006 National Research Council (NRC) universal equation calculates the energy requirement of growing dogs based on predicted adult body weight, but evidence suggests a revision may be required. This study investigates the energy requirements of seventeen Norfolk terrier puppies over their first year (10 to 52 weeks). Puppies were individually fed complete and balanced diets in amounts to maintain an optimal body condition score (BCS), recording intake daily and body weight and BCS weekly. To monitor health a veterinary examination, haematology and plasma biochemistry and serum measures of bone turnover were undertaken every 12 weeks. Skeletal development was assessed using dual-energy X-ray absorptiometry (26 and 52 weeks). Puppies were clinically healthy with normal skeletal development and healthy growth throughout. The energy intake to achieve this was significantly lower than that predicted by the NRC (2006) equation at all time points, with largest mean difference of 285 kJ/kg^0.75 per day at 10 weeks. If fed according to the NRC 2006 equation, dogs would have been in positive energy balance, possibly leading to obesity. These data support a revision to the NRC (2006) equation.

Equations used to develop commercial dog food feeding guidelines and Canadian owner feeding practices in 2018

Feeding guidelines on commercial dog food packages provide a suggested starting point for food provision for dogs. The equations used to develop commercial dog food feeding guidelines and the owner feeding practices surveyed were examined in this study. The equations used to develop feeding guidelines and the energy density calculation method (Traditional Atwater or Modified Atwater equation) were investigated for 200 dry dog foods sold in Canada. Not all energy densities of products were calculated using the modified Atwater equation, a requirement if claiming compliance with the Association of American Feed Control Officials (AAFCO). Commercial feeding guidelines provide conservative estimates of pet dog energy needs. A survey of dog owners' feeding practices was conducted, with 739 responses analyzed. Respondents generally took appropriate action to manage the weight of their dogs through both exercise and dietary management. Further investigation should explore how owners may be successfully managing their dogs' weight without veterinary supervision.

Energy Consumption of Young Military Working Dogs in Pre-Training in Germany

Simple Summary

Appropriate energy supply adjusted to the requirements of military working dogs at pre-training is a basic prerequisite for working dogs, so they are fully able to exercise. Therefore, twenty Belgian Shepherds var. Malinois were accompanied for four weeks during pre-training as military working dogs, and the amount of energy intake was evaluated. Changes in body constitution were assessed by measuring body weight and shoulder height, as well as thickness of subcutaneous fat tissue, and of Musculus sacrocaudalis dorsalis lateralis (MSCDL). Energy intake amounted to, on average, 244 kcal/kg body weight (BW)^0.75 daily. Changes to body constitution (increases in body weight, shoulder height, and thickness of the MSCDL, as well as a reduction of the thickness of the subcutaneous fat tissue lying on the MSCDL) might be attributed to training-induced muscle growth and physiological growth in size. In addition to training intensity, influences of ambient temperature and physiological body growth seemed to be important contributing factors in the supply of energy for military working dogs (MWDs) during pre-training.

Abstract

Many factors have specific effects, in varying degrees of intensity, on the metabolic energy requirements of working dogs. Appropriate energy supply adjusted to the requirements of military working dogs at pre-training is a basic prerequisite for working dogs, so they are fully able to exercise. Therefore, more knowledge obtained under standardized conditions would be advantageous. Twenty intact Belgian Shepherds var. Malinois at the age of 12 months were accompanied for four weeks during pre-training (odour detection, obedience training, and protection work) as military working dogs (MWDs) in Germany (ambient temperature about 7.8 °C), and the amount of energy intake was evaluated. To assess changes in body constitution, body weight and shoulder height were measured, and the thickness of subcutaneous fat tissue (SCF), and of Musculus sacrocaudalis dorsalis lateralis (MSCDL), were recorded via ultrasound. Energy intake amounted to, on average, 244 ± 34 kcal/kg body weight (BW)^0.75 daily. Increases in body weight, shoulder height, and thickness of the MSCDL, as well as a reduction of SCF thickness lying on the MSCDL, were observed. Changes of body constitution might be attributed to training-induced muscle growth and physiological growth in size. In addition to training intensity, influences of ambient temperature and physiological body growth seemed to be important contributing factors in the supply of energy for MWDs during pre-training.

Adult dogs of different breed sizes have similar threonine requirements as determined by the indicator amino acid oxidation technique

Threonine (Thr) requirements for immature (growing) Beagles have been determined, but little knowledge is available on Thr requirements for maintenance in mature dogs. Moreover, differences of Thr requirements among different breeds or sizes of adult dogs have not been investigated. The objective of the present study was to determine Thr requirements in adult dogs of three different breeds using the indicator amino acid oxidation (IAAO) technique. In total, 13 adult dogs were used, 4 Miniature Dachshunds (5.8 ± 0.4 kg body weight [BW]; 3 spayed and 1 neutered), 4 spayed Beagles (9.3 ± 0.6 kg BW), and 5 neutered Labrador Retrievers (30.5 ± 1.7 kg BW). Dogs were fed a Thr-deficient diet (Thr = 0.23%) and randomly allocated to receiving one of seven concentrations of Thr supplementation (final Thr concentration in experimental diets was 0.23%, 0.33%, 0.43%, 0.53%, 0.63%, 0.73%, and 0.83%; as fed basis) for 2 d. After 2 d of adaptation to the experimental diets, dogs underwent individual IAAO studies. During the IAAO studies, total daily feed was divided into 13 equal meals; at the sixth meal, dogs were fed a bolus of l-[1-13C]-Phenylalanine (Phe) (9.40 mg/kg BW), and thereafter, l-[1-13C]-Phe (2.4 mg/kg BW) was supplied with every meal. Before feeding the next experimental diet, dogs were fed a Thr-adequate basal diet for 4 d (Thr = 0.80% as fed basis) in known amounts that maintained individual dog BW. Total production of 13CO2 during isotopic steady state was determined by enrichment of 13CO2 in breath samples and total production of CO2 measured using indirect calorimetry. The mean requirements for Thr, defined as the breakpoint, and the 95% confidence interval (CI) were determined using a two-phase linear regression model. For Miniature Dachshunds, the two-phase model was not significant, and Thr requirements could not be determined. Mean Thr requirements for Beagles and Labradors were 72.2 and 64.1 mg/kg BW on an as-fed basis, respectively. The requirement for Thr between these two dog breeds was not different (P > 0.10). Thus, the data for Beagles and Labradors were pooled and a mean requirement for Thr was determined at 66.9 mg/kg BW, and the 95% CI was estimated at 84.3 mg/kg BW. In conclusion, estimated Thr requirements for Beagles and Labradors did not differ, and these recommendations are higher than those suggested by NRC (2006) and AAFCO (2014) for adult dogs at maintenance.

Effect of a Leucine/Pyridoxine Nutraceutical on Caloric Intake and Body Composition of Obese Dogs Losing Weight

The aim of this 29-week randomized, positively and negatively controlled study was to investigate whether a nutraceutical containing 1 g leucine and 13 mg pyridoxine can enhance weight loss while maintaining lean muscle mass in obese dogs. Twenty-four healthy, 2-year-old beagles were initially divided into obesification (n = 18) or ideal body weight groups (n = 6). After obesification, the 18 dogs were divided into three weight loss groups and fed one of the following over 12 weeks: nutraceutical with canned adult diet (CAD; ObN), placebo with CAD (ObP), or a canned therapeutic weight loss diet (WLD). Dogs in the ideal body weight (IBW) group were fed maintenance calorie requirements with CAD over 12 weeks. Based on MANOVA, ObN and WLD lost similar amounts of total weight (3.6 ± 0.9 vs. 4.4 ± 1.1 kg, respectively) and fat mass (3.1 ± 0.6 vs. 3.9 ± 0.8 kg, respectively) after 12 weeks of treatment, and more than ObP (1.1 ± 1.2 kg weight; 0.9 ± 1.0 kg fat; p < 0.0001). These data show the nutraceutical is a promising option for successful weight loss in dogs. Maintenance levels of CAD were able to induce weight loss without risk of hypo- or anorexia, or the need to switch diets or restrict energy intake.

Effects of diet on body weight, body composition, metabolic status, and physical activity levels of adult female dogs after spay surgery

Neutering is a risk factor for pet obesity, which reduces the quality and length of life. Dietary interventions may serve as preventive and therapeutic options for pet obesity. The objective of this study was to evaluate the effects of specially formulated diets on body weight (BW), body composition, and blood hormones and metabolites of adult female dogs after spay surgery. All procedures were approved by the University of Illinois Institutional Animal Care and Use Committee prior to experimentation. Twenty-eight healthy adult intact female Beagles (3.02 ± 0.7 yr; 10.28 ± 0.8 kg; body condition score [BCS]: 4.98 ± 0.57) were used in a longitudinal study. Twenty-four dogs were spayed and randomly allotted to one of three experimental diets: 1) moderate-protein, moderate-fiber diet (control; COSP), 2) high-protein, high-fiber diet (HP-HF), or 3) high-protein, high-fiber diet plus omega-3 and medium-chain fatty acids (HP-HF-O). Four dogs were sham-operated and fed the control diet (COSH). Food intake, BW, BCS, blood hormones and metabolites, body composition (via dual-energy X-ray absorptiometry scans), and voluntary physical activity (via Actical devices) were measured over time. After spay, dogs were fed to maintain BW for 12 wk (restricted phase), then allowed to overeat for 12 wk (ad libitum phase). Change from baseline data was analyzed for treatment, time, and treatment × time effects as well as treatment, feeding regimen, and treatment × feeding regimen effects. During the first 12 wk, HP-HF and HP-HF-O had lower (P < 0.01) blood cholesterol than COSH and COSP. During the second 12 wk, HP-HF and HP-HF-O ate more (P < 0.01) food (g/d) than COSH. BCS change for COSP was greater (P < 0.01) than COSH from week 21 to 24, but HP-HF and HP-HF-O were not different. When comparing data by feeding regimen, HP-HF and HP-HF-O had a greater reduction in serum cholesterol (P < 0.001) than COSH and COSP. During the second 12 wk, all spayed dogs consumed more (P < 0.01) food than COSH. However, COSH, HP-HF, and HP-HF-O had a lower (P < 0.001) increase in BCS than COSP. HP-HF-O and COSH had similar serum leptin during weeks 12 to 24. COSP had higher (P ≤ 0.01) serum C-reactive protein than HP-HF-O. Overall, body fat increase in COSP was greater (P < 0.05) than for COSH at week 24, while HP-HF and HP-HF-O were intermediate. Our results indicate that an HP-HF diet can limit weight gain and body fat increase and attenuate serum cholesterol, triglycerides, and leptin concentrations in dogs after spay surgery.

Environmental Impacts of a Pet Dog: An LCA Case Study

The number of pet animals in the European Union is increasing over the last decades. Few studies with a limited focus in terms of impacts and life cycle stages exist that assess the environmental impacts of dogs. This paper addresses the entire life cycle of a dog. An LCA study on an average dog was conducted considering the pet food and dog excrements, i.e., urine and feces. Fifteen impact categories were analyzed. An average dog has a climate change and freshwater eutrophication potential of around 8200 kg CO2eq and 5.0 kg Peq., respectively. The main contribution to most impact categories over the dog’s life is caused by pet food. Freshwater eutrophication is mainly determined by the dog´s urine and feces. Feces also have a significant contribution to the category of freshwater ecotoxicity. Impacts increase significantly with increasing weight and a longer lifetime of the dog as well as low collection rates of the feces. This LCA study reveals that pet dogs can have a significant environmental impact, e.g., around 7% of the annual climate change impact of an average EU citizen. Optimizing pet food and increasing the feces´ collection rate can reduce the impacts.

Neutering in dogs and cats: current scientific evidence and importance of adequate nutritional management

Neutering or spaying is a commonly recommended veterinary procedure. However, veterinarians are often confronted with conflicting findings and differences in concepts regarding practice and proper nutritional management after the procedure. The objective of the present review was to bring to light the most recent literature, summarise it and discuss the findings focusing on the risks and benefits of neutering in dogs and cats, and to determine the appropriate nutritional management for these animals.

Behavioural risks in female dogs with minimal lifetime exposure to gonadal hormones

Spaying of female dogs is a widespread practice, performed primarily for population control. While the consequences of early spaying for health are still being debated, the consequences for behaviour are believed to be negligible. The current study focused on the reported behaviour of 8981 female dogs spayed before 520 weeks (ten years) of life for reasons other than behavioural management, and calculated their percentage lifetime exposure to gonadal hormones (PLGH) as a proportion of their age at the time of being reported to the online Canine Behavioral Assessment and Research Questionnaire (C-BARQ). We found that 23 behaviours differed between entire and spayed dogs, of which 12 were associated with PLGH and 5 with age-at-spay (AAS). Two behaviours, chewing and howling, were significantly more likely in dogs with longer PLGH. In contrast, longer PLGH was associated with significantly reduced reporting of 10 (mostly unwelcome) behaviours. Of these, one related to fearfulness and three to aggression. The current data suggest that dogs' tendency to show numerous behaviours can be influenced by the timing of spaying. They indicate how female dog behaviour matures when gonadal hormones are allowed to have their effect. The differences reported here between undesirable behaviours of spayed and entire dogs were in the range of 5.33% and 7.22%, suggesting that, for some dogs, partial or complete denial of maturation may reduce howling and chewing and improve retrieval and recall, but have other undesirable consequences. Veterinarians may take these data into account to discuss the risks and benefits of spaying with clients, and the timing of the procedure.

Predictive equations of maintenance energy requirement for healthy and chronically ill adult dogs

Maintenance energy requirement (MER) is the energy amount necessary for dogs to maintain their weight and body condition. Some factors can influence the MER, such as gender, age, neutering status and also diseases. The present retrospective study aimed to evaluate MER of adult dogs with several diseases and compare with the MER of healthy adult dogs, observing the influence of parameters such as body condition score (BCS), neutering status, gender, age, diagnosis and type of food on MER of these dogs. A total of 165 adult dogs with weight changes of ≤5% were included and divided in groups according to diagnosis. Mean MER for healthy dogs was 86.09 kcal/BW^0.75 , which differed from NRC and FEDIAF recommendations for inactive adult dogs (p = .047). Lowest MERs were of the endocrinopathies (78.52 ± 19.32 kcal/BW^0.75 ), orthopaedic diseases (59.71 ± 19.30 kcal/BW^0.75 ) and neurologic diseases (78.83 ± 32.66 kcal/BW^0.75 ) groups. Gastrointestinal diseases (99.59 ± 20.36 kcal/BW^0.75 ), orthopaedic diseases (59.71 ± 19.30 kcal/BW^0.75 ) and neoplasia (95.61 ± 21.02 kcal/BW^0.75 ) groups were the only groups that differed from the mean MER of healthy adult dogs. Regarding BCS, for each increasing point in a 9-point scale, there was a decrease of 9.8 kcal/BW^0.75 on MER, independent of diagnosis (p < .0001; r²  = .55). There was no difference regarding breed size gender and age, but neutered dogs presented lower MER (p = .031). Based on data obtained from the present study, it can be concluded that it is necessary to consider BCS, age, neutering status and diagnosis when calculating MER, both in healthy dogs and chronically ill dogs.

Metabolisable energy content in canine and feline foods is best predicted by the NRC2006 equation

Although animal trials are the most accurate approach to determine the metabolisable energy (ME) content of pet food, these are expensive and labour-intensive. Instead, various equations have been proposed to predict ME content, but no single method is universally recommended. Data from canine and feline feeding studies, conducted according to Association of American Feed Control Officials recommendations, over a 6-year period at a single research site, were utilised to determine the performance of different predictive equations. Predictive equations tested included the modified Atwater (MA equation), NRC 2006 equations using both crude fibre (NRC 2006cf) and total dietary fibre (NRC 2006tdf), and new equations reported in the most recent study assessing ME predictive equations (Hall equations; PLoS ONE 8(1): e54405). Where appropriate, equations were tested using both predicted gross energy (GE) and GE measured by bomb calorimetry. Associations between measured and predicted ME were compared with Deming regression, whilst agreement was assessed with Bland-Altman plots. 335 feeding trials were included, comprising 207 canine (182 dry food; 25 wet food) and 128 feline trials (104 dry food, 24 wet food). Predicted ME was positively associated with measured ME whatever the equation used (P<0.001 for all). Agreement between predicted and actual ME was worst for the MA equation, for all food types, with evidence of both a systematic bias and proportional errors evident for all food types. The NRC 2006cf and Hall equations were intermediate in performance, whilst the NRC 2006tdf equations performed best especially when using measured rather than predicted GE, with the narrowest 95% limits of agreement, minimal bias and proportional error. In conclusion, when predicting ME content of pet food, veterinarians, nutritionists, pet food manufacturers and regulatory bodies are strongly advised to use the NRC 2006tdf equations and using measured rather than predicted GE.

Concentrations of macronutrients, minerals and heavy metals in home-prepared diets for adult dogs and cats

Pet owners often don't acknowledge the need for home-prepared diet formulation by a trained professional and may use recipes from sources such as the internet. Macronutrient and mineral composition of home-prepared diets were analyzed and compared to NRC and FEDIAF recommendations, and heavy metal concentrations were analyzed and compared to FDA maximum tolerable levels (MTL) for dogs and cats. Recipes of home-prepared diets for adult dogs (n = 75) and cats (n = 25) were evaluated. Analyses of protein, fat, and fiber were performed according to AOAC, and mineral and heavy metal analyses were performed using inductively coupled plasma optical emission spectrometry (ICP-OES). None of the diets supplied recommended levels of all nutrients evaluated, and more than 84.0% of diets presented three or more nutrients below recommendations. Nutrients with most levels below recommendations were calcium and potassium in recipes for dogs and iron and zinc in recipes for cats. As for heavy metals, levels of lead, cobalt, mercury, uranium, and vanadium were above MTLs. Results suggest that home-prepared diets may be a health risk to dogs and cats if not properly formulated. Furthermore, the chronic heavy metal intake must be better elucidated in order to understand the full impact of results.

Neutering increases the risk of obesity in male dogs but not in bitches - A cross-sectional study of dog- and owner-related risk factors for obesity in Danish companion dogs

Knowledge of risk factors for canine obesity is an important pre-requisite of effective preventative strategies. This study aimed to investigate risk factors for canine obesity in adult companion dogs across Zealand, Denmark. Client-owned dogs (>2 years of age and without chronic illness) were recruited and examined at eight companion animal veterinary practices in areas with varying socio-economic characteristics. The body condition score (BCS) of the dogs was examined by two investigators based on a 9-point scoring scheme. Dog owners answered a questionnaire that had prompts regarding: 1) dog characteristics, including neuter status, 2) owner characteristics, 3) feeding and exercise practices and 4) the owners' attachment to the dog. The effect of these factors on BCS and the risk of being heavy/obese (BCS scores 7-9) were analysed in two separate analyses. A total of 268 dogs were included in the analysis, of which 20.5% were found to be heavy/obese. The average BCS was 5.46. In terms of dog characteristics, neutering dramatically increased both BCS and the risk of being heavy/obese in male dogs but not in bitches. BCS and the risk of being heavy/obese increased in senior bitches and decreased in senior male dogs. The risk of being heavy/obese was higher in dogs with overweight and obese owners. Regarding feeding and exercise practices, providing only one meal per day increased BCS and risk of being heavy/obese. Treats during relaxation increased the risk of dogs being heavy/obese. It also increased the dogs' BCS, but only if the owners were overweight or obese. An increased duration of daily walking increased the risk of the dog being heavy/obese, but only if the owner was overweight or obese. Allowing the dog to run free in the garden/property decreased the risk of the dog being heavy/obese. The owners' attachment to the dog was not associated with the dogs' BCS or dogs' being heavy/obese. An important and novel finding was that neutering increased the risk of being overweight or obese for male dogs while bitches were at risk irrespective of neuter status. Furthermore, a complex interaction between owners' weight status, feeding practices and the risk of dogs being overweight or obese was found, which stresses the need to consider companion animal obesity from a One Health perspective in future prospective studies. Finally, this study was unable to confirm that canine obesity is a product of owners being too attached to their dogs.

Benefits of dietary supplements on the physical fitness of German Shepherd dogs during a drug detection training course

A high standard of physical fitness is an essential characteristic of drug detection dogs because it affects not only their ability to sustain high activity levels but also their attention and olfaction efficiency. Nutritional supplements could improve physical fitness by modulating energy metabolism, oxidative processes, and perceived fatigue. The aim of this study was to investigate the physiological and biochemical changes induced by submaximal exercise on drug detection dogs (German Shepherd breed) and to assess whether a dietary supplement improves their physical fitness. During a drug detection dog training course, seven dogs were fed with a basal diet (Control Group) for three-month period, while a further seven dogs were fed with a basal diet as well as a daily nutritional supplement containing branched-chain and limiting amino acids, carnitine, vitamins, and octacosanol (Treatment Group). At the end of this period, individual physical fitness was assessed by making each subject take a graded treadmill exercise test. A human heart rate monitor system was used to record the dog's heart rate (HR) during the treadmill exercise and the subsequent recovery period. The parameters related to HR were analysed using nonparametric statistics. Blood samples were collected before starting the nutritional supplement treatment, before and after the treadmill exercise and following recovery. Linear mixed models were used. The dietary supplements accelerated HR recovery, as demonstrated by the lower HR after recovery (P<0.05) and Time constants of HR decay (P<0.05), and by the higher Absolute HR Recovered (P<0.05) recorded in the Treatment group compared with the Control dogs. The supplemented dogs showed the lowest concentrations of creatine kinase (CK; P<0.001), aspartate aminotransferase (AST, P<0.05) and non-esterified fatty acids (NEFA; P<0.01) suggesting a reduction in muscle damage and improvement of energy metabolism. These data suggest that this combined supplement can significantly enhance the physical fitness of drug detection dogs.

The Ecological Paw Print of Companion Dogs and Cats

As an indicator of sustainable development, the ecological footprint has been successful in providing a basis for discussing the environmental impacts of human consumption. Humans are at the origin of numerous pollutant activities on Earth and are the primary drivers of climate change. However, very little research has been conducted on the environmental impacts of animals, especially companion animals. Often regarded as friends or family members by their owners, companion animals need significant amounts of food in order to sustain their daily energy requirement. The ecological paw print (EPP) could therefore serve as a useful indicator for assessing the impacts of companion animals on the environment. In the present article, we explain the environmental impact of companion dogs and cats by quantifying their dietary EPP and greenhouse gas (GHG) emissions according to primary data we collected in China, the Netherlands, and Japan and discuss how to reduce companion dietary EPP and GHG emissions in order to understand the sustainability of the relationship between companion animals and the environment.

Kastration der Hündin – neue und alte Erkenntnisse zu Vor- und Nachteilen

Die Beratung von Hundehaltern bezüglich der Vorteile und Nachteile sowie des optimalen Zeitpunktes der Kastration einer Hündin ist komplex und sollte sich auf verlässliche Daten aus der Wissenschaft stützen sowie individuelle Belange berücksichtigen. Bei genauerer Betrachtung der aktuellen Publikationen zu diesem Thema fällt auf, dass einige lange für robust gehaltene Informationen etwas angepasst oder aktualisiert werden müssen. Ein offensichtlicher Vorteil der elektiven Kastration ist, dass Erkrankungen der Ovarien und sexualsteroidabhängige Erkrankungen wie Metropathien nicht auftreten. Weiterhin ist ein gewisser protektiver Effekt einer frühzeitigen Kastration auf die Entstehung von Mammatumoren anzunehmen, wenngleich dafür derzeit eine schwache wissenschaftliche Evidenz besteht und der Effekt vermutlich geringer ausfällt, als in einigen älteren Publikationen angegeben wurde. Die Kastration hat jedoch auch Nachteile. Als häufigste negative Folge wird seit Jahrzehnten die Harninkontinenz beschrieben. Aussagen zur Inzidenz sowie zu weiteren Einflussfaktoren, wie Kastrationszeitpunkt in Bezug zur Pubertät, sind jedoch uneinheitlich. Aktuell werden vor allem das gehäufte Auftreten verschiedener Tumorerkrankungen, die nicht direkt mit dem Reproduktionstrakt in Verbindung stehen, sowie ein höheres Risiko für Erkrankungen des Bewegungsapparats bei kastrierten Tieren diskutiert. Weitere Einflussfaktoren wie der Ernährungszustand des Hundes, Alter und/oder Haltung wurden jedoch häufig nicht erfasst. Die Datenlage zur Auswirkung der Kastration auf den Stoffwechsel und das Immunsystem der Hündin ist derzeit ungenügend. Wünscht der Tierbesitzer eine Kastration, bedarf es in jedem Fall einer eingehenden Beratung, die individuelle, rasse- und haltungsbezogene Aspekte einschließt. Derzeit ist eine Kastration am ehesten zwischen der ersten und zweiten Läufigkeit zu empfehlen, da ein gewisser protektiver Effekt auf die Entstehung von Mammatumoren anzunehmen ist und das Risiko unerwünschter Nebenwirkungen nach heutigem Wissensstand moderat ausfällt.

A randomized, double-blind, prospective, placebo-controlled study of the efficacy of a diet supplemented with curcuminoids extract, hydrolyzed collagen and green tea extract in owner's dogs with osteoarthritis

BACKGROUND

We have previously demonstrated that a mixture of Curcuminoids extract, hydrolyzed COllagen and green Tea extract (CCOT) inhibited inflammatory and catabolic mediator's synthesis by bovine and human chondrocytes. A randomly allocated, double-blind, prospective, placebo-controlled study was performed to evaluate the efficacy of a diet containing this CCOT mixture on dogs with naturally occurring osteoarthritis (OA). Therefore, 42 owner's dogs with OA were randomly assigned to receive for 3 months an experimental diet (control) or the same diet supplemented with CCOT.

RESULTS

Ground reaction forces did not show statistical differences between groups. After 3 months of feeding, there was a significant reduction of pain at manipulation in the CCOT group, but not in the control group. The evolution for pain at manipulation depended on the diet. The three other parameters evaluated by veterinary subjective assessment (lameness, pain at palpation and joint mobility) did not show statistical differences. Concerning owner subjective assessment, pain severity score worsened in the control group but remained stable in CCOT group. The evolution for pain severity depended on the diet. No statistical difference was found for pain interference, except for the ability to rise to standing from lying down, which was significantly improved in the CCOT compared to the control group. Serum OA biomarkers did not show statistical differences.

CONCLUSIONS

Objective variables measured, such as ground reaction forces and OA biomarkers, did not show statistical differences. However, indicators of pain appeared reduced in dogs receiving CCOT mixture for 3 months. The difference of evolution between groups suggests that a greater number of dogs may be necessary to reach a stronger effect on other parameters.

A new model for evaluating maintenance energy requirements in dogs: allometric equation from 319 pet dogs

Reports concerning maintenance energy requirements (MER) in dogs are common but most of the data cover laboratory or utility dogs. This study establishes those of healthy adult pet dogs and the factors which cause these energy requirements to vary. Within the framework of a nutrition teaching exercise, each student followed a pet from his entourage and gathered accurate records of its feeding habits. Data have been restricted to healthy adult dogs with an ideal body weight (BW) which did not vary more than 5 % during the study period. A total of 319 eligible records were analysed using multiple linear regression. Variation factors such as ownership, breed, sex and neutered status, bedding location, temperament and feeding habits were then analysed individually using a non-parametric model. Two models result from this study, one excluding age (r² 0·813) and a more accurate one which takes into consideration the age in years (r² 0·816). The second model was assessed with the main variation factors and shows that: MER (kcal) = k₁ × k₂ × k₃ × k₄ × k₅ × 128 × BW^0·740 × age^−0·050/d (r² 0·836), with k₁ the effect of the breed, k₂ the effect of sex and neutered status, k₃ the effect of bedding location, k₄ the effect of temperament and k₅ the effect of the type of feed. The resulting model is very similar to the recommendations made by the National Research Council (2006) but a greater accuracy was obtained using age raised to a negative power, as demonstrated in human nutrition.

[Unusual case of struvite urolithiasis in a dog. A case report]

A dog was referred for nutrition consultation after surgical removal of struvite uroliths from the bladder. Inspection of the dog's current ration revealed a pronounced vitamin-A deficiency together with a marked deficiency of protein, phosphorus and magnesium. Therefore, a supersaturation of the urine with ammonium, magnesium and phosphate, the three constituents of struvite, as a cause of struvite calculi formation appears rather unlikely. Vitamin-A deficiency can promote urinary infections and consequently struvite stone formation because of the lack of the protective effect of vitamin A on the epithelia of the urinary tract. Not only common causes for struvite urolith formation, including urinary supersaturation with stone-forming constituents and urinary tract infection, but also less common causes, including vitamin-A deficiency, which was the presumed trigger in the present case study, have to be taken into consideration. Dietetic measures appear to be a useful tool in such cases to prevent uroliths from reoccurring.

A survey of feeding, activity, supplement use and energy consumption in North American agility dogs

A survey was designed and administered at eighteen agility competitions across the Northeast and Midwest USA in 2015 to obtain information regarding competition level, training, feeding practices, owner-reported weight, body condition score (BCS) and supplement use. Average energy intake per d from reported consumption was assessed for all dogs in ideal body condition based on manufacturers' or US Department of Agriculture database information. To assess the respective parameters across competition levels (novice, open, master/elite), non-parametric or parametric ANOVA or χ² was used to determine significance. There were 494 respondents with usable data. Results showed that approximately 99 % of respondents used treats and 62 % utilised supplements. Of the respondents, 61 % fed primarily commercial dry food. Approximately 25 % of owners fed foods other than commercial dry (i.e. raw/home-prepared or freeze-dried). This 25 % of non-traditional diets included: 11 % home-prepared raw/cooked diets, 11 % commercial raw/cooked diets, and the remaining 3 % were fed commercial freeze-dried raw products. The remaining 14 % fed a mix of commercial dry food and raw/home-cooked blend. Average BCS was 4·7 (sd 1·1). Mean energy consumption of 238 dogs (BCS 4-5/9) was 444 (sd 138) kJ/kg body weight^0·75 per d (106 (sd 33) kcal/kg body weight^0·75 per d), with no significant differences observed between dogs at different levels of competition. The mean percentage of energy from treats was 15·1 (sd 12·7) % of overall energy consumption.

Inaccurate Assessment of Canine Body Condition Score, Bodyweight, and Pet Food Labels: A Potential Cause of Inaccurate Feeding

The objectives were to investigate owners’ ability to assign the correct bodyweight (BW) and body condition score (BCS) to their dog and to interpret wet and dry pet food labels by estimating how much to feed daily. One hundred and seventy-four questionnaires were completed. Owner estimated BW was compared to actual BW, correct being defined within ±10% of actual BW. Correct interpretation of the total amount of food required was determined by the number of cans (±25% of cans) required for wet food and grams (±20% of grams) for dry food, based on the dog’s actual BW, the feeding guidelines on the label, and a comparison with the owner’s estimate. Eleven percent of owners overestimated BCS and 19% overestimated BW. Only 48% of owners could correctly estimate their dog’s BW. Only 23% and 43% of owners could correctly estimate how much wet and dry food to feed, respectively. Chi-square analysis demonstrated a significant positive association for owners correctly estimating their dog’s BW and interpreting the wet pet food label. Many owners are not aware of their pet’s BCS and BW and cannot accurately interpret pet food labels. Further owner education to improve these skills is needed if dogs are to be fed correctly.

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.

Obesity Prevention and Weight Maintenance After Loss

Obesity is one of the most prevalent medical diseases in pets. Outcomes are often disappointing; many animals either fail to reach target weight or regain weight. This article discusses managing obesity, focusing on prevention. It gives guidance on establishing monitoring programs that use regular body weight and condition assessments to identify animals at risk of inappropriate weight gain, enabling early intervention. Weight management in obese animals is a lifelong process. Regular weight and body condition monitoring are key to identifying animals that rebound early, while continuing to feed a therapeutic weight loss diet can help prevent it from happening.

Comparative locomotor costs of domestic dogs reveal energetic economy of wolf-like breeds

The broad diversity in morphology and geographic distribution of the 35 free-ranging members of the family Canidae is only rivaled by that of the domesticated dog, Canis lupus familiaris. Considered to be among nature's most elite endurance athletes, both domestic and wild canids provide a unique opportunity to examine the variability in mammalian aerobic exercise performance and energy expenditure. To determine the potential effects of domestication and selective breeding on locomotor gait and economy in canids, we measured the kinematics and mass-specific metabolism of three large (&gt;20 kg) dog breed groups (northern breeds, retrievers, and hounds) of varying morphological and genomic relatedness to their shared progenitor, the gray wolf. By measuring all individuals moving in preferred steady-state gaits along a level transect and on a treadmill, we found distinct biomechanical, kinematic, and energetic patterns for each breed group. While all groups exhibited reduced total cost of transport (COT) at faster speeds, the total COT and net COT during trotting and galloping were significantly lower for northern breed dogs (3.0 and 2.1 J∙kg−1∙m−1, respectively) relative to hound (4.2 and 3.4 J∙kg−1∙m−1, respectively) and retriever dogs (3.8 and 3.0 J∙kg−1∙m−1, respectively) of comparable mass. Similarly, northern breeds expended less energy per stride (3.47 J∙kg−1∙stride−1) than hounds or retrievers (4.97 and 4.02 J∙kg−1∙stride−1, respectively). These results suggest that, in addition to their close genetic and morphological ties to gray wolves, northern breed dogs have retained highly cursorial kinematic and physiological traits that promote economical movement across the landscape.

A systematic review for the antidepressant effects of sleep deprivation with repetitive transcranial magnetic stimulation

BACKGROUND

Sleep deprivation (SD) and repetitive transcranial magnetic stimulation (rTMS) have been commonly used to treat depression. Recent studies suggest that co-therapy with rTMS and SD may produce better therapeutic effects than either therapy alone. Therefore, this study was to review the current findings to determine if rTMS can augment the therapeutic effects of SD on depression.

METHODS

Embase, JSTOR, Medline, PubMed, ScienceDirect, and the Cochrane Central Register of Controlled Trials were searched for clinical studies published between January 1985 and March 2015 using the search term "rTMS/repetitive transcranial magnetic stimulation AND sleep deprivation AND depress*". Only randomized and sham-controlled trials (RCTs) involving the combined use of rTMS and SD in depression patients were included in this systematic review. The scores of the Hamilton Rating Scale for Depression were extracted as primary outcome measures.

RESULTS

Three RCTs with 72 patients that met the inclusion criteria were included for the systematic review. One of the trials reported skewed data and was described alone. The other two studies, which involved 30 patients in the experimental group (SD + active rTMS) and 22 patients in the control group (SD + sham rTMS), reported normally distributed data. The primary outcome measures showed different results among the three publications: two of which showed great difference between the experimental and the control subjects, and the other one showed non-significant antidepressant effect of rTMS on SD. In addition, two of the included studies reported secondary outcome measures with Clinical Global Impression Rating Scale and a self-reported well-being scale which presented good improvement for the depressive patients in the experiment group when compared with the control. The follow-up assessments in two studies indicated maintained results with the immediate measurements.

CONCLUSIONS

From this study, an overview of the publications concerning the combined use of rTMS and SD is presented, which provides a direction for future research of therapies for depression. More studies are needed to confirm whether there is an augmentative antidepressant effect of rTMS on SD.