Weight control

Overweight dogs

Weight management is problematic throughout the global canine population, with more than 50% of dogs either overweight or obese. The condition is almost always due to the dog receiving too much food or too many snacks in proportion to its size and level of exercise. One of the reasons behind the obesity pandemic in the pet population is poor-quality pet food. The majority of pet food on the market is based on plant starch and carbohydrates, which provide an excess of easily digestible carbohydrates for energy metabolism. Energy that is not consumed by the body shortly after digestion is stored as fat. Certain metabolic diseases can also lead to the accumulation of fat and result in obesity. A weight increase of approximately 10% is overweight, with an increase of 20% or more constituting obesity. Therefore, a dog weighing ten kilos would be considered overweight by gaining only one additional kilo of weight, whereas an extra two kilos of weight would make the same dog obese. The condition of a dog’s body can be assessed by observing the ribs, the abdominal line, and the waistline and also by palpating the ribs and spine. Being overweight poses a significant risk of developing other diseases and shortens the life expectancy of the dog by up to 20%.

Body condition score

The body condition score can be assessed from very underweight to obese. There are several types of rating scales, but in general body condition is divided into three categories: underweight, normal weight, and overweight.

• Underweight: In a very underweight dog, the ribs and other bones of the body are clearly visible from a distance, and the dog has no noticeable layer of fat. The muscles may be atrophied. The dog’s abdomen is retracted sharply upwards, and the waist is clearly distinguishable when the dog is viewed from above.
• Normal weight: The dog’s ribs may be slightly visible and can be felt through the skin. The ribs are covered with a thin layer of fat, and the waist can be seen when viewed from above. The abdominal line stands out and ascends slightly; in breeds with a deep chest, the abdominal line stands out and ascends markedly. The muscles are clearly distinguishable. Viewed from above, the dog has a clearly recognisable waist with a narrowing between the chest and abdomen, which may resemble an hourglass.
• Overweight or morbidly overweight: The ribs are covered with a clear layer of fat and may or may not be palpable through the skin. The abdominal line is straight with a thick layer of fat beneath the abdomen. The belly line of a significantly overweight dog hangs down, and the neck and the root of the tail are covered with a thick layer of fat. The waist does not stand out at all when viewed from above.

Being overweight also has an impact on a dog’s behaviour. A healthy dog of normal weight ​​is usually happy to move and can easily jump into a car, for example. An overweight dog is slow, needs to be encouraged to move, and has difficulty breathing. Alertness is low in an overweight dog, with the animal sleeping a lot and showing little interest in its surroundings.

Causes of overweight

Feeding

By far the biggest cause of overweight in dogs is an unbalanced relationship between feeding and exercise. Dogs may be very picky about the food they eat, in which case owners typically give them leftovers and treats. Owners may not be able to correctly judge the amount of food to serve, or dogs are given food with too much energy, too much protein, and too much fat in relation to their needs. There are also differences in energy content and energy density between different dog foods. A particular food might be absorbed more efficiently, meaning that when it is fed in the same amount as another less efficient food, it will cause weight gain. As opportunists, dogs quickly learn to beg for food and snacks, making it difficult for owners to resist giving a small treat from time to time, especially since dogs can be so sweet when begging. Snacks and treats given in addition to the normal daily amount of food and exceeding daily energy needs often result in dogs becoming overweight. Unfortunately, many dog ​​owners do not realize that an energy-intensive treat can contain up to half of a dog’s daily energy needs.

Hormonal changes

After castration or sterilisation, a dog’s hormonal activity changes and its metabolism slows, which puts the animal at risk for weight gain; however, weight gain can be prevented by paying careful attention to the dog’s diet following surgery. Diseases that cause hormonal changes, such as hypothyroidism, can also result in weight gain.

Age

As the metabolism of an aging dog slows, energy from food is more easily stored as fat. Unlike cats, the energy needs of dogs decrease with age. Puppies and young dogs are more active than older dogs, and the amount of exercise is often greater in a young dog than in an aging dog. Also, older dogs are more likely than young dogs to have osteoarthritis, which impairs their ability to exercise and predisposes them to obesity.

Gender

Female dogs are more sensitive to weight gain than males. Hormonal changes in females have a greater effect on fat accumulation than in male dogs.

Breed

Some dog breeds are known to have a good appetite and are more susceptible to gaining weight than others. Examples of such breeds are Beagles, Bulldogs, Dachshunds, Cocker Spaniels, and Labrador Retrievers (1). A genetic defect (2) has been found in the Labrador Retriever and the Flat-Coated Retriever that causes a feeling of hunger and impairs the feeling of satiety. The physical build of a dog also affects its ability to move. For example, in brachycephalic breeds, the structure of the skull and muzzle can affect breathing, meaning the dogs cannot cover the same distances as long-nosed breeds. Breeds that are susceptible to hip defects as a result of breeding may also be more susceptible to weight gain due to reduced mobility. Some breeds may also have a genetic predisposition to hypothyroidism. Many giant breeds are prone to weight gain because they have a good appetite but a slower metabolism than small dogs, and many giant breed dogs do not get enough exercise.

Diseases and problems caused by overweight

Being overweight predisposes to a variety of health problems, and the life expectancy of an overweight dog is shorter than that of a dog with normal weight. In puppies, excess weight can result in various growth disorders. Being overweight is also a significant risk for dogs requiring general anaesthesia for surgery because it makes them more vulnerable to various complications than normal dogs, and recovery times for overweight dogs are also much longer. Obesity has been found to predispose dogs to a variety of tumours and cancers.

Adipose tissue plays an active role in the body. It produces enzymes and hormones that are involved in the regulation of blood pressure, appetite, immune response, blood sugar, and inflammation, for example. If the amount of adipose tissue in the body becomes too high, the substances it produces will be disrupted. Excess adipose tissue produces inflammatory mediators that can lead to low-grade general inflammation, such as osteoarthritis, dermatitis, urinary tract infection, etc., which in turn can worsen the body’s inflammatory response. One of the main substances produced by adipose tissue is adiponectin, which inhibits the formation of inflammatory mediators and sensitizes the body to insulin. Adiponectin levels are reduced in obese dogs.

Being overweight puts dogs at an increased risk of developing diabetes. Obesity has not been shown to be a direct cause of type 2 diabetes in dogs, but it can also cause so-called insulin resistance and hyperinsulinemia. Obesity also predisposes dogs to pancreatitis, which further encourages the onset of diabetes. Constantly elevated blood sugar can promote the destruction of pancreatic beta cells, so obesity can indirectly cause diabetes. However, as the dog loses weight, insulin levels may decrease, and insulin sensitivity may increase again (1).

The heart of an obese dog is subjected to much greater strain than that of a normal dog. Furthermore, because a dog cools itself by panting, if it is unable to increase its respiratory rate sufficiently due to obesity, it may face a potentially life-threatening situation in hot weather resulting from overheating.

Weight loss

While there is no easy shortcut to weight loss, a reduction in body weight of only a few percent can provide an overweight dog with health benefits. It is essential to adapt a dog’s diet and exercise to its size, age, gender, and other health conditions. An overweight dog often has to lose weight under the supervision of a veterinarian with the help of a special diet and a proper exercise programme. The ideal and safe weight loss goal is 1–2% of the dog’s total weight per week. An appropriate diet limits a dog’s energy intake while ensuring availability of essential nutrients. A veterinary diet designed for weight management maintains a feeling of satiety and provides all essential nutrients and sufficient amounts of protein. Satiety also reduces a dog’s tendency to beg, which further contributes to the success of the diet. Home-cooked human food is often high in calories and does not provide dogs with important nutrients, so dieting with home-cooked food is definitely not recommended. A dog should not be given any snacks during the diet, and diet instructions should be followed. Weight loss that happens too quickly is not healthy for a dog because it takes a toll on the muscles. During weight loss, a dog should be weighed regularly at a veterinary clinic. The ideal diet is rich in easily digestible and absorbable protein, contains plenty of soluble and insoluble prebiotic fibre, and has a low glycaemic index and low energy content. Critical for any dog undergoing weight loss is the period that follows once the desired weight has been achieved. During this period, it is necessary to maintain a healthy diet and exercise routine to prevent weight gain. It can take several months for the body and metabolism to adapt to the new food.

Brit VD Obesity

Brit VD Obesity is a veterinary diet designed for overweight and obese dogs for weight management and weight loss. It is also suitable for maintaining ideal weight after castration or sterilization. The protein sources for Brit VD Obesity are easily digestible sheep and turkey, which help maintain muscle mass. A low content of fat (9%) and low energy density prevent weight gain and support the utilization of body fats. Sheep and turkey proteins are easily digestible and provide sufficient amounts of essential amino acids for good overall condition. The source of carbohydrates in Brit VD Obesity is yellow pea, which has an excellent ratio of both soluble and insoluble fibre and has a low glycaemic index, meaning it helps balance postprandial blood sugar levels. Yellow pea is very digestible and absorbable and is also a good source of protein. The high content of fibre (8.5%) helps maintain a feeling of satiety, which reduces the dog’s need to beg for treats and thus makes achievement of the target weight more likely. Brit VD Obesity is a gluten-free and chicken protein-free diet that can reduce the risk of AFR.

The amino acids L-carnitine and taurine are added to the food because they play important roles in fat metabolism and maintenance of muscle condition. Glucosamine and chondroitin sulfate are articular cartilage building blocks and chondroprotectives that improve mobility in overweight dogs. Selenium and vitamins C and E are added to Brit VD Diabetes as antioxidants to reduce oxidative stress. The omega-3 fatty acids EPA and DHA affect fat metabolism and can promote long-term glucose balance. The live probiotic E. faecium has been added to the food to encourage healthy bacterial flora in the gut.

For weight loss, the Brit VD Obesity diet should be used for at least two months. Dogs must not be offered any treats, other dog food, or any human food during this time. The ideal weight loss goal is 1–2% of the dog’s total weight per week.

1) Kylliäinen, A. Evaluation of dog breed and overweight as possible risk factors for diabetes mellitus: Licentiate thesis, Faculty of Veterinary Medicine, Department of Clinical Equine and Small Animal Medicine, University of Helsinki 4/2016.
2) Raffan, E et al. A deletion in the canine POMC gene is associated with weight and appetite in obesity prone Labrador Retriever dogs. Cell Metabolism; 3 May 2016; DOI: 10.1016/j.cmet.2016.04.012