Overweight and obesity are among the most common conditions veterinarians see in both dogs and cats .
Yet weight-loss plans for pets are frequently unsuccessful, with a high drop-out rate . In one study, over half of participating dogs actually gained weight .
In a new study published in the journal Animals , we argue weight management in pets often fails because we view it too narrowly - as a nutritional problem that can be solved simply by feeding the animals less.
Yet evidence suggests to manage weight in pets, we also need to attend to animal behaviour, and human-animal interactions are a huge part of that.
How do I know if my pet is overweight or obese?
Body condition scoring is the most common method vets use to classify animals as underweight, ideal weight or overweight.
The Global Pet Obesity Initiative uses a scale of 1-9, with a body condition score of 5 representing ideal body weight.
Each category between 1-9 represents a 10% difference in weight. For example, an animal with a body condition score of 6 out of 9 is 10% overweight, while a score of 7 out of 9 means the pet is 20% overweight. Obesity is defined as having a body condition score of 8 out of 9 (30% overweight) or above.
How common are overweight and obesity in pets?
Globally, about half of the pet dog and cat population is overweight or obese, with middle-aged pets most commonly affected.
The largest study (conducted in the United States), comprising almost 5 million dogs and more than 1 million cats, reported excess weight and obesity in 50% and 13% of adult dogs respectively, and in 45% and 22% of cats. High rates of overweight and obesity have been reported in Australia , New Zealand , Europe and China .
Overweight and obesity are more common in animals who are highly motivated by food, those with reduced physical activity (including indoor-housed cats) and, in some studies, those who've been desexed . Some breeds, such as Labrador retrievers, have a genetic predisposition to obesity.
Owner activity levels, lifestyle and the nature of their bond with pets also influence the pets' risk of obesity. When it comes to animals they love, many owners have " weight blindness " - they don't even see their pets as overweight.
Why should we worry about overweight and obese pets?
Just like for humans, overweight and obesity in pets are associated with increased risk of diseases such as diabetes, heart disease, skin disease, and cancer.
Excess weight exacerbates conditions like osteoarthritis, and increases the risk of heat stroke. Lifespan is reduced in obese dogs and cats .
Carrying excess weight can prevent animals from engaging in behaviours like exercise, play and interaction with other animals and people. The World Small Animal Veterinary Association describes obesity as the most important global animal welfare issue.
Why does traditional weight management fail?
The standard approach to help your pet lose weight involves calorie restriction, increased exercise and regular weighing. It sounds so simple. And yet this approach often fails.
Pets who are fed less show hunger and increase their food-seeking behaviour, making owners feel guilty. They eat their reduced portions quickly, using the additional time to look for or demand more food.
Animals accustomed to receiving treats or scraps from the family dinner table may protest their exclusion from familiar routines. Such behaviour is difficult to resist - many owners succumb and provide treats.
Caloric restriction alters metabolism, which can initially increase weight gain, and the lack of progress can be demotivating. Some dogs and cats are fearful in veterinary settings, and owners find regular weigh-ins too traumatic.
All these factors can put owners (and animals) off sticking with the weight-loss plan.
How to help your pet lose weight successfully
1. Use accurate information to formulate a weight management plan
All pets should be regularly weighed and scored on their body condition. Pet owners can use body condition scoring sheets for dogs and cats to do this at home.
Fearful pets who don't like being weighed at the vet can be weighed on home scales. Importantly, take note of what your pet eats (including treats and scavenged foods) and share this information with your vet.
A complete dietary history helps in planning a diet compatible with your pet's preferences. High-calorie foods could be substituted for ones with fewer calories, for example.
2. Diets should be low calorie, high satisfaction
Weight-loss diets should be nutritionally complete. The best diets are those that are reduced in calories, but still leave animals feeling satisfied after a meal.
Low-calorie treats can be factored into the daily ration so that animals don't miss out.
3. Provide opportunities to hunt, find and forage food
Feeding the daily ration in multiple smaller meals can burn additional calories and increase time spent eating.
Allowing animals to "hunt" for food by providing food in puzzle feeders , scatter feeding or setting up "treasure hunts" allows them to express natural behaviours. Animals may use up more calories and experience more pleasure from foods they can chew . They may also spend less time "asking" owners for food.
4. Be prepared for begging
Animals used to receiving table scraps will dial up their attention-seeking behaviour in an increased effort to be rewarded. It can be hard to resist such antics, but rewarding begging with a food morsel will only encourage pets to intensify their efforts.
Instead, try to preempt them by providing a rewarding alternative activity (such as giving a dog a toy to chew on their bed) while you eat your meal in peace.
Non-food related activities, including sensory gardens and digging pits , climbing opportunities or interactive toys may also provide suitable distractions.
Weight loss in pets is about giving them more years of good-quality life. With the right tools - not just calorie counting - we can keep our pets happy and healthy.
Anne Quian has been a consultant or volunteer for a range of organisations including Animal Management in Rural and Remote Indigenous Communities (AMRRIC) iCatCare, the Cat Protection Society of NSW, the Royal Agricultural Society and RSPCA Australia. She has donated to several charities including Animals Australia, AMRRIC, the Cat Protection Society of NSW, RSPCA NSW and VALE. She is a member of the Australian Veterinary Association and the Australian and New Zealand College of Veterinary Scientists, and a Diplomate and Subcommittee Chair of the European College of Animal Welfare and Behaviour Medicine in Animal Welfare Science, Ethics and Law. She has been a recipient of an Australian Companion Animal Health Foundation Grant, and has undertaken two project-based residencies at The Ethics Centre.
Rimini Quinn is a member of the Australian and New Zealand College of Veterinary Scientists (Veterinary Behaviour Chapter), the Pet Profession Guild and is a Fear Free certified professional. She donates to Vets against live export (VALE) and Animals Australia.
