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Focus - Companion Animal - November 2019

The role of nutrition in managing obesity

With research showing that more than two thirds of dogs and more than a third of cats are overweight, Caroline Burke BSc RVN, outlines the important role of nutrition in managing these companion animals’ weight

Latest research shows that 65% of dogs and 39% of cats are overweight and obese1,2 meaning that vets and nurses are more likely to see a patient with a body condition score (BCS) of six or above (on a nine-point scale) than one at ideal weight and shape (BCS four to five). In response to the growing numbers of overweight and obese patients, the British Small Animal Veterinary Association (BSAVA) released their position statement, recognising obesity as a disease in cats and dogs, encouraging both veterinary surgeons and owners to be ‘proactive in addressing obesity and its consequences, in order to improve the health and welfare of pets’.3

Consequences of obesity
The links between obesity and increased incidence of other conditions such as joint disease, diabetes mellitus, urinary disease, skin disease and tumours are well documented.4 Such conditions can lead to additional costs for the pet owner. Overweight cats and dogs may have a reduced life expectancy, with studies indicating that it may be as much as 2.5 years less in overweight dogs,5 and just under two years in cats6 (Figures 1 and 2). By encouraging these owners and their pets to undertake a weight-management programme we can help them live longer, healthier lives.

Owner education
Studies highlight that pet owners are more likely to underestimate the BCS of an overweight pet.7 The first step in the patient’s weight-management programme is, therefore, to help the client recognise their pet is overweight. For veterinary professionals, BCS is not only a basis for diagnosis and calculating the cat or dog’s ideal weight but crucially provides a method of guiding and communicating to the pet owner to understand the impact of this disease on their pet. The now well-established nine-point BCS model has been further adapted by Royal Canin to include six dog and one cat morphology, to make communication about obesity even more specific to pet owners with different sized dogs.
Once the client has recognised their pet is overweight or obese, they can be referred to a weight-management clinic, where they can receive additional support to help their pet reach their ideal weight and shape.

Developing a weight-management plan
Obesity is often referred to as an imbalance of calorie intake and expenditure. Therefore, it is very common for people to recommend reducing calorie intake and increasing exercise as part of a weight management plan.
While the importance of exercise for cats and dogs should not be ignored, a 2019 study highlighted that exercise alone wasn’t as effective as a specifically formulated weight management diet in promoting weight loss.8 Therefore, the focus for any weight-management plan should be reducing calorie intake.8

Reducing energy Intake

A detailed history of the pet’s current diet and eating habits should be taken. Using a food diary or questionnaire (Figure 3, for example) can provide vets and nurses with valuable information and can be very helpful for owners to document their pets’ food history and begin to understand the impact of extra calories.

Given the nature of obesity and how drastically calories need to be cut to induce weight loss, it is no wonder that a major concern for owners whose pets are undertaking a weight-management programme is that they will be hungry and the impact this will have on the perception of begging behaviour.9 Evidence in human studies show that some foods are more effective than others in reducing hunger, and foods high in protein, fibre, carbohydrates or water are the most satiating. Results from a trial performed by Weber et al (2007) indicated that a diet containing high protein and high fibre had a greater satiating effect then either protein or fibre alone.10 To this end, feeding a specifically formulated weight-management diet is recommended.

Long-term management
Weight re-gain after a successful weight-loss programme is common in cats and dogs. In fact, the results of a 2012 study suggest that nearly 50% of dogs who successfully complete a weight loss programme will re-gain weight.11 This is because
the energy requirements needed to maintain an ideal weight and shape post weight loss are lower than the energy requirement of cats and dogs who have never been obese.11,12 It is therefore recommended that patients remain on their weight management diet long term in order to prevent weight re-gain.

Obesity is a complex disease and one that presents clear health-and-welfare issues for cats and dogs. By having a strong practice protocol in place for weight management, and utilising a specifically formulated weight-management diet, practices can help owners make long-term changes that benefit their pet.

View References
  1. German AJ, Woods GT, Holden SL et al. Dangerous trends in pet obesity. Veterinary Record 182 (1). 2018
  2. Courcier EA, O’Higgins R, Mellor DJ et al. Prevalence and risk factors for feline obesity in a first opinion practice in Glasgow, Scotland. Journal of Feline Medicine and Surgery 12. 2010;10: 746-753.
  3. BSAVA Obesity position statement:
  4. German AJ. The growing problem of obesity on dogs and cats. Journal of Nutrition 2006; 136: 1940-1946.
  5. Salt C, Morris PM, Wilson D, et al. Association between life span and body condition in neutered client-owned dogs. J. Vet. Intern. Med: 1-11. 2018.
  6. Teng KT, McGreevy PD, Toribio J. et al. Strong associations of 9 point body condition scoring with survival and life span in cats. J. Feline Med Surg. 2018. 1-13.
  7. Courcier EA, Yam PS, Thomson RM, et al. Owner misperception of canine body shape: an important determinant of canine obesity? 12th Symposium of the International Society for Veterinary Epidemiology and Economics, Durban, South Africa. 2009. 10-14 Aug.
  8. Chapman M, Woods GRT, Ladha C, Westgarth C, et al. An open-label randomised clinical trial to compare the efficacy of dietary caloric restriction and physical activity for weight loss in overweight pet dogs. The Veterinary Journal. 2019;243: 65-73.
  9. Flanagan J, Bissot T, Hours MA, et al. Success of a weight loss plan for overweight dogs; the results of an international weight loss study. PLoS One 12(9): e0184199. 2018.
  10. Weber M, Bissot T, Serve E, et al. A high protein, high-fibre diet designed for weight loss improves satiety in dogs. Journal of Veterinary Internal Medicine. 2017: 21;1203-1208.
  11. German AJ, Holden SL, Mather NJ, et al. Low-maintenance energy requirements of obese dogs after weight loss. Br J Nutr. 2010: 106 (1); S93-6.
  12. Seriser S, Vialle S, Martinez E, et al. Weight loss and post weight loss maintenance energy requirement of obese colony cats. Proc. 21st ECVIM Congress, Sevilla, 2011: 209-10.
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