Obesity in dogs
Obesity in dogs. Different options to reduce weight and to come back to a fit and healthy life
Obesity is a global disease affecting more than half a billion humans. Each year, at least 2.8 million people die because of being overweight or obese. Overweight and obesity have an adverse influence on the body’s metabolism including blood pressure, cholesterol, triglycerides and insulin resistance. Coronary heart disease, ischemic stroke and type 2 diabetes mellitus as well as different cancers are consequences of overweight and obesity and consequently lead to an increased mortality risk. Similar to the human population, an increasing prevalence of obesity in pets has been observed over the past decades. Approximately one third of dogs who are presented to veterinarians are obese.
Obesity in dogs augments the risk to develop several diseases, such as endocrinopathies, musculoskeletal disorders, urinary incontinence, hypertension, insulin resistance, exercise intolerance, different cancers and a shortened life span (1).
Reducing weight would bring a lot of advantages for the dog, such as improved mobility, improved respiratory function, resolution of metabolic disturbances and overall an improved quality of life. How can this be achieved? Most commonly, overweight dogs are obliged to undergo a dietary energy restriction in form of a purpose-formulated diet. Several clinical trials have shown that this strategy is very successful. Unfortunately, this same success cannot be observed in clinical settings implying the dog s owner. But why is the weight loss slowed down or not reached in a home environment? The problem is the animals’s diet-implemented hunger which causes increased begging and scavenging activity. Owners have problems to resist this behavior and often stop the program in the end (1).
During the last years, in order to overcome this difficulty, new and improved diets have been developed with the idea to decrease the feeling of hunger and to improve the voluntary food intake without loosing palatability. Most diets try to balance protein and fibre content in order to reduce hunger but keep a good taste. Some dietary products decreased their nutrient density by expanding kibble volume with air or water. However, several strategies can be applied. A recent study from Hours et al aimed to compare the performance of novel commercially-available dog weight loss diets using housed research colonies. The researchers applied two different diets, one “high protein high fibre” diet and a “moderate protein high fibre” diet differing in energy content and macronutrient profile. The group performed two studies with two groups of dogs in each study. The dogs received either one of the two diets in a seven day period using a crossover design. As a results, the two studies could demonstrate that the voluntary food intake was significantly reduced using the high protein high fibre compared to the moderate protein high fibre diet in terms of energy intake. No difference was observed for gram weight intake and palatability. In conclusion, the studies of Hours et al could show that foods with different contents can decrease the voluntary food intake without reducing the good taste. The observed effects might be due to the decreased energy and fat content and the increased fibre content from different fibre sources. However, the study results obtained must still be confirmed for obese dogs on controlled weight loss programs (2).
Another study conducted by Vitger and colleagues added an exercise program to the weight loss program of obese dogs. The researchers aimed to monitor gene expression related to glucose metabolism and also evaluated different inflammatory biomarkers. Vitger et al hypothesized that a weight loss program containing an energy-restricted diet combined with physical exercises would improve the glucose homeostasis and lower the inflammatory markers compared to a weight loss program without physical exercise. The study desing implemented that all participating dogs had to be overweight but otherwise healthy. They were divided in two different groups, one group being on a fitness and diet program, the other group only on a diet. The study included a 12 week calorie restricted program for all dogs. The fitness diet group had to pass an additional 1 hour of treadmill exercise at land and underwater three times a week and had to upsolve daily walks of at least 30 min. The physical activity was measured with an accelerometer for the whole study period. Besides, blood samples were taken in order to monitor different biomarkers. A total of 16 dogs completed the study, 8 in each of the groups. They achieved the same weight loss. Insulin resistance was determined from plasma insulin and c-peptide as well as the homeostasis model assessment. Inflammation and dyslipidemia were monitored with circulating leptin, adiponectin, c-reactive protein, monocyte chemoattractant factor-1, interleukin 8 and cholesterol. It could be observed that the measured blood biomarkers did not differ between the groups. Within the groups, it was shown that leptin decreased, as well as IL-8, MCP-1 and CRP decreased in the fitness and diet group at 6 weeks and c-peptide at 12 weeks. In the diet only group, c- peptide and HOMA decreased at 6 weeks and c-peptide at 12 weeks. In conclusion from this study, the veterinarians could demonstrate that in both groups the weight loss resulted in minor improvements of immunometabolic health, whereas the addition of physical activity did not bring further benefits (3).
Dog owners should act when having an overweight or obese dog in order to reduce its weight and facilitate is every-day life with lowering the risk of different disease. Many different diet products for dogs are on the market and the choice is not easy in order to find the best option. Dog owners should go for one strategy and be strict to bring their dog’s diet program to a success. In this way, overweight dogs will regain a fit and healthy life.
1. L. B. Radakovich, M. P. Truelove, S. C. Pannone, C. S. Olver, K. S. Santangelo, Clinically healthy overweight and obese dogs differ from lean controls in select CBC and serum biochemistry values. Vet Clin Pathol, 0/0 2017.
2. M. A. Hours, E. Sagols, A. Junien-Castagna, A. Feugier, D. Moniot, I. Daniel, V. Biourge, S. Samuel, Y. Queau, A. J. German. Comparison of voluntary food intake and palatability of commercial weight loss diets in healthy dogs and cats. BMC Veterinary Research, 12:274, 2016.
3. A. D. Vitger, B. M. Stallknecht, J. E. Miles, S. L. Hansen, A. Vegge, C. R. Bjornvad. Immunometabolic parameters in overweight dogs during weight loss with or without an exercise program. Dom Ani End, 10.007. 2016.