Dogs are considered overweight when they are 10-20% above their ideal body weight. A study by the Association for Pet Obesity Prevention in 2018 showed that that 56% of pet dogs in the USA are overweight. A study in 2019 by Banfield Veterinary Hospitals confirmed that more than half of adult dogs seen in their hospitals were overweight. Up to 37% of dogs are overweight by the age of 6 months.
Obesity is defined as being > 20% above ideal body weight. Between 25 and 30% of all dogs are obese. For dogs over 5 years of age, an even higher percentage of dogs are obese. Cairns have been cited by a UK study as being at high risk for obesity (see source 7 for reference).
Overweight dogs need not reach the point of obesity to begin experiencing the adverse effects of excess weight. Being 10% overweight has been shown to decrease the dog’s lifespan by 1/3 and increases the risk of heart, kidney and liver disease, arthritis, diabetes and cancer. Overweight pregnant bitches have a higher rate of dystocia (difficulty in delivering due to size of puppies).
The practice of free feeding (leaving food available to be consumed at will) is an important contributing factor to the development of obesity. Free feeding, although easy for the owner, isn’t best for the dog. A dog may eat out of boredom. Dogs may lack impulse control and not stop eating when they have consumed sufficient food to meet their needs. With scheduled feeding, the owner can control food intake and adjust to the dog’s weight. As one of the first signs a dog is not well is food refusal of food, scheduled feeding facilitates early detection that something is amiss.
Other contributing factors to obesity include:
- Obesity in puppyhood
- Multiple people in the home involved in feeding chores.
- Mismatch between diet and exercise.
- Too many treats and table scraps.
- Medications causing increased appetite (prednisone, phenobarbital etc.)
- Neuter / Spay: desexed dogs are about twice as likely to become obese (32% vs 15%) and need reduced food allocation to maintain a healthy weight.
- Age: the amount of energy needed is dependent on age. Failure to adjust for transitions from puppy to adult, and adult to senior, can result in over feeding.
- Hypothyroidism and Cushing’s disease are often associated with obesity and should be considered when a previously lean dog develops obesity.
- The number of meals per day does not have a bearing on the risk of obesity.
Assessing Obesity
Weight is the first indicator of obesity. Keeping a close eye on your dog’s weight can help you identify weight gain before it becomes obvious just by looking at your dog. Early identification of increasing weight allows for small adjustments in food intake.
Veterinarians typically use body condition scores to assess the nutritional status of dogs. These use several simple physical assessments to help determine if a dog is overweight including:
- A tummy tuck – a visible rise behind the ribs when viewed from the side.
- The waist – a visible waist when viewed from above.
- Fat layer around the thorax – dogs with ideal body weight will have only a thin layer of fat in this area. Feel for a fat pad over the prosternum (breastbone).
- Ribs and vertebra should be easily palpable, but not easily visible, in most breeds.
- Fat pad at the base of the tail. The presence of a fat pad at the base of the tail indicates about 10-20% above ideal weight.
Examples of body condition scores:
https://www.aaha.org/aaha-guidelines/life-stage-canine-2019/nutritional-assessment/body-and-muscle-condition-score/
https://vet.osu.edu/vmc/sites/default/files/images/Body%20condition%20score%20chart%20dogs_0.pdf
Managing obesity
Here are some tips for helping your dog maintain or regain a healthy body weight.
- Check with your veterinarian for guidance on weight loss and ideal food intake given breed, age, and activity level.
- Make sure everyone in the home with responsibility for feeding the dog (including treats) is on the same page and understands the need to limit intake.
- If more than one person feeds the dog, have a system to communicate when a meal has been given (your dog will never tell!).
- If currently using free feeding, transition to a scheduled feeding program and remove uneaten food after 10-15 minutes.
- Measure out meals rather than eyeballing it.
- Set out a daily treat allocation; use lower calorie treats. Cut treats into smaller portions. Use a portion of the daily food allocation for treats.
- Use healthy treats – veggies, fruit etc. Be aware that some fruits and veggies can have very high sugar contents (carrots!).
- Switch to a food formula with a lower caloric content (many commercial pet foods have formulas for weight management or senior dogs).
- Use slow feeder bowls and snuffle mats. Slowing down the rate of food consumption can help the dog feel satiated.
- Use active feeding strategies that promote exercise while eating e.g., food dispensing toys, kibble trails in the yard, tossing food for the dog to chase.
- Increase your dog’s daily exercise.
- Don’t forget to include the caloric content of things like bully sticks and other chews in the daily food allowance.