A new drug which has already been used successfully in the US is now approved for use by European vets. It works mainly by altering the way the body handles fat in the diet, so the dog feels full earlier and may beg less, thus making it easier for the owner to implement and commit to a weight loss programme long-term. It has been developed specifically for use in dogs and is not approved for use in any other animals or humans. When used in combination with a controlled diet and exercise programme, the new treatment can dramatically increase the chances of long-term success.

Experts estimate that between 25-40% of Europe’s dogs are overweight or obese and are therefore at risk of long-term health problems¹. Research has shown that overweight dogs may live up to two years less than those that are at normal weight² and the list of serious health problems linked to obesity include heart disease³, diabetes⁴ and osteoarthritis⁵.

Being overweight also reduces the quality of life of many dogs, as they are unable to exercise without becoming too tired, out of breath or too hot. This in turn reduces the amount of fun that owners can have with their pet, and potentially damages the pet/owner relationship.

According to Dr Alex German, who runs Europe’s first companion animal weight management referral clinic at the University of Liverpool (www.pet-slimmers.com), the rise in dog obesity has a number of basic causes: “Our modern, work-oriented lifestyles mean that many pets do not get the exercise that they should. Instead of forging the owner/pet bond with the experience of shared exercise and play, many owners use treats as a way of showing their love for their dog.”

The combination of too many calories taken in and not enough calories burnt off, is the basic reason why our pets are putting on weight, says Dr German.

“Of course, prevention is better than cure,” he says, “and getting into good habits when you first get a new dog is the best strategy. But in cases where the dog has become overweight, the answer is to follow a diet and exercise plan devised by a veterinarian.”

However, owners often find it difficult to stick to a weight loss programme, especially if their pet seems to be continually hungry.

“The new drug option means that vets now have an extra tool that can help owners to follow and be successful with a weight loss plan,” says Dr German.

The new treatment is being marketed by Pfizer Animal Health as an integral part of a weight loss programme alongside dietary and exercise modification and is available only from veterinary surgeons. The drug comes in liquid form and can be either added to the dog’s food once a day or put directly into the dog’s mouth using a syringe. A course of treatment may last up to 12 months, and the dose is adjusted regularly to maintain a healthy, gradual and tailor-made weight loss.

“This is not a cure for obesity, nor is it meant to be used as the sole method of weight loss,” says Dr German. “For long term success, owners still have to be motivated to follow an integrated weight loss programme, which includes other elements such as modified diet and/or exercise. However, it can help owners to succeed with getting their dogs to lose weight successfully.”

Note to the editor: A selection of images and further press background information is available on request (email Justin Courtney: jcy@garnett-keeler.com).

References:

1. Wolfsheimer KJ. Obesity: In: Ettinger SJ, Feldman EC eds. Textbook of Veterinary Internal Medicine: diseases of the dog and cat, vol 1. 5th ed, Philadelphia PA, WB Saunders. 1996; 70-72.

2. Remillard RL. Obesity: A disease to recognize and manage. In: Ettinger SJ, Feldman EC eds. Textbook of Veterinary Internal Medicine: diseases of the dog and cat, vol 1. 6th

ed, Philadelphia PA, WB Saunders. 2005;76-77.

3. German AL. The growing problem of obesity in dogs and cats. J Nutr. 2006;136:S1940-1946.

4. Larson BT, Lawler DF, Spitznagel EL Jr, et al. Improved glucose tolerance with lifetime diet restriction favorably affects disease and survival in dogs. J Nutr. 2003;133:2887-2892.

5. Impellizeri JA, Tetrick MA, Muir P. Effect of weight reduction on clinical signs of lameness in dogs with hip osteoarthritis. J Am Vet Med Assoc. 2000;7:1089-1091.

BACKGROUND ON OBESITY AND EXCESS WEIGHT IN DOGS

Overweight and obese dogs are very common in Europe. Their prevalence has risen dramatically in recent years: In the 1960s and 70s, 6-12% of dogs in the US were estimated to be obese; more recent studies in the US, Europe and Australia have reported that number to range from 25-40%⁶.

Obesity is a recognised disease and as such, dramatically reduces a dog’s lifespan and quality of life and increases the risk of other serious diseases. In a study comparing the lifespan of paired dogs, where one was fed 25% less than the other, the food-restricted dogs’ median lifespan was more than 15% longer than the control dogs, and the age at which they showed signs of chronic disease was significantly delayed.⁷

The majority of treatments consist of diet and exercise modification. However, owners find this difficult to adhere to due to the behaviour of the dog, lifestyle factors and the belief that feeding is an important element of the pet-owner bond.

Medical risks

Reduced Activity

Excess weight can reduce the quality of a dog’s life by decreasing mobility and activity levels, which in turn can make weight loss more difficult.

The extra strain the weight puts on the dog can result in:

• Increased demand on the heart and respiratory systems
• Impaired pulmonary function – extra fat restricts lung capacity and requires the diaphragm to work harder
• Reduced heat tolerance – which leads to discomfort and a reduced inclination for activity

Orthopaedic disorders

Being overweight greatly increases the risk of osteoarthritis due to the increased pressure on the joints. Studies have shown that even a moderate amount of weight loss reduced hind-limb lameness of dogs with hip osteoarthritis and, in fact, weight loss is considered a first line treatment for dogs who are carrying too much weight.⁸

Diabetes

Studies have shown that the majority of diabetic dogs are obese and difficulties to achieve glycaemic control have been shown in obese diabetic dogs. For example, in one study, when the bodyweight of obese, diabetic dogs was reduced to pre-diabetic levels, their glucose tolerance and insulin response returned to normal.⁹

Other risks

Canine obesity has also been associated with cardiac and respiratory disease, diabetes and increased surgical complication and anaesthetic risk.

Causes of obesity

The causes of obesity are quite complex. The most common cause is an excess intake of or inadequate use of energy, resulting in a positive energy balance.

Factors contributing to this include:

• Feeding behaviour of the owner: table scraps, treats, cheap dog food, number of meals, extra food from family members
• Owners of overweight dogs are often overweight themselves
• Emotional factors: owners often think ‘food is love’; feed out of guilt; overfeeding is often a projection of their own situation

Other causes include:

• Breed (genetic factors): obesity is most common in Retrievers, Beagles, Basset Hounds, Cocker Spaniels, Daschunds, Shelties, German Shepherds and Terriers
• Neutered dogs are more likely to be obese
• Underlying health conditions – endocrinopathies and conditions where activity is reduced such as osteoarthritis, respiratory disease, cardiovascular disease
• Pharmaceuticals: progesterones, corticosteroids, anti-convulsant drugs

Benefits of Weight Loss

• Dogs with an optimal weight live longer than obese dogs
• Weight loss is a first line treatment for osteoarthritis and respiratory and cardiac diseases
• Weight loss of 11% has been associated with improvement in clinical signs of osteoarthritis
• In a Pfizer clinical study, weight loss of 11.8% bodyweight was associated with an increase in activity levels