Your Pet & You
Bigger is not always Better Is your Pet is Obese?
We all love to share our food with our furry counterparts. However, sharing everything with our four-legged friends - especially sugary foods, isn't a very good idea. Breeds such as Labrador Retrievers, Pugs, Beagles and Dachshunds are prone to gaining weight and becoming obese, and obesity could lead to various health issues.
Obesity is defined as an accumulation of excessive amounts of adipose tissue in the body, and is the most common nutritional disorder in companion animals. It causes impairment of health, welfare and quality of life. It can affect all types of pets or companion animals, and there are numerous factors that predispose an individual to obesity including genetics, the amount of physical activity, and the energy content of the diet but the main cause usually seen is from eating too much or not exercising enough, although some diseases can cause obesity too.
There is a distinction between being overweight and being obese. Being overweight can be defined as having a body composition where the levels of body fat exceed those considered optimal for good health. Obesity can be defined as being overweight to the extent that it has serious effects on the individual's health becomes likely.
Animals are termed obese when their body weight exceeds about 15-20 percent above ideal recommended body weight. Excess fat negatively impacts a dog's health and longevity. Thus, overweight and obese companion animals lose out both in terms of health related quality of life and life expectancy.
There are several factors that make obesity more likely in pets for example in dogs/cats:
Breed: Some dog and cat breeds have a higher propensity to becoming overweight and obese than others. For example, among dogs, Labradors and golden retrievers are always more at risk than any other breed.
Age: The risk of being obese increases with age in companion animals.
Sex: Apart from older dogs, obesity is reported to be more common in females.
Owner: Obese owners are more likely to have obese dogs, perhaps because they are less likely to exercise their dog, or less able to recognise obesity.
Exercise: Lack of exercise not only predisposes to higher levels of obesity in dogs and cats, but also exacerbates health problems linked to being overweight. For instance, in cats, indoor confinement increases the risk of developing diabetes mellitus.
Certain Disease Conditions: Hypothyroidism decreases metabolism and activity levels, resulting in obesity, and hyperadrenocorticism causes weight gain due to a cortisol-driven increase in appetite.
How to Know If your Pet is Obese?
All dogs have an ideal weight for their size and breed. The first step in dealing with an overweight or obese dog/cat is to recognise and acknowledge that there is a problem. For dogs and cats, there are a few simple checks one can do:
Feel and observe the outline of pet's ribs without excess fat covering: Rib coverage is one of the most important measurements to help identify if your dog is overweight. It is very simple and easy, and can be done at home, by placing hand palm down and feeling the ribs of dogs/cats such as the knuckles just behind the shoulder blades. It is also a good method for measuring weight loss progress between formal weightings. Veterinarians determine if a pet is overweight or obese by its body condition score (BCS). They assess the amount of stored fat and assign a number to score if a pet is underweight, overweight, or just right. Most veterinarians use a body condition scoring system on a scale of either 1-5 (3 is normal) or 1-9 (4.5 is normal).
Feel and observe pet's waist: The waist should be clearly visible when viewed from above.
Observe pet's belly: The belly of dogs should always be tucked up when viewed from the side indicating no excess fat.
Signs in Overweight Dogs/Cats
Collar belt needs loosening;
Difficulty in walking;
Shortness of breath;
Sleeping more than usual.
Health Risks involved with Obesity
There are multiple changes that take place in the body of animals due to obesity which make them susceptible to several health related problems. The common health risks involved with obesity in companion animals are:
Diabetes Mellitus: One of the most common complications of obesity in companion animals is the development of diabetes mellitus. Obesity causes an increase in the secretion of insulin in response to the increased blood glucose level in the overweight dogs and cats. When requirements for insulin exceed the ability of the body to produce insulin, diabetes mellitus develops. If the need for insulin increases over a long period of time, the cells in the pancreas which produce insulin can actually 'burn out,' again resulting in diabetes. The symptoms commonly seen in diabetic dogs are:
Excessive water consumption - polydipsia;
Frequent and/or excessive urination - polyuria;
Greater than average appetite - polyphagia;
Cloudy eyes - Cataracts.
Damage to Joints, Bones, and Ligaments: Arthritis is one of the most common ailments seen in middle-aged to older pets. Even younger dogs and cats (under the right circumstances but obese) can suffer from arthritic changes. Arthritis causes changes within the affected joints that are painful for the affected pet. Studies have suggested that approximately twenty-five percent of overweight dogs develop serious joint complications. The bones, joints, muscles, and associated tendons and ligaments - all work together to give the dog smooth and efficient movement, but when they are required to carry excess weight, they start getting damaged. Arthritis can develop and the pain and joint changes associated with hip dysplasia can become markedly more severe. Extra tension on joints caused by an increased weight load leads to damage of certain ligaments. Certain breeds of dogs, such as Dachshunds are prone to develop intervertebral disc disease (slipped disc). Carrying extra weight increases the probability that they will develop this painful and sometimes debilitating condition. Some of the common signs of arthritis in companion animals include limping, difficulty in moving, lameness in one or both legs, tiredness, irritability and muscle atrophy. Arthritis in cats can be particularly hard to spot. Many arthritic cats simply become less active.
Cardiovascular Problems: As in humans, overweight dogs and cats also tend to have increased blood pressure (hypertension). Hypertension has been reported in 23 to 45 percent obese dogs. The heart has an increased work load since it must pump additional blood to excess tissues. This can lead to congestive heart failure. In dogs, as in people, the magnitude of obesity has been found to be directly correlated to the severity of heart dysfunction, that is, the fatter the animal is, the worse the heart functions.
Difficulty Breathing: In overweight animals, the lung tissues cannot function properly. The additional fat in the chest restricts the full expansion of the lungs. The extra fat in the abdomen pushes against the diaphragm, which separates the abdominal cavity from the chest. This results in less space in the chest for the lungs to expand on inspiration. Moreover, the increased quantity of tissue due to obesity puts an increased demand on the lungs to supply oxygen. These changes are especially serious in dogs that may already have a respiratory disease.
Decreased Liver Function: The liver stores fat so when a dog is overweight, an increased amount of fat builds up in the liver. This is called hepatic lipidosis, and it can result in decreased liver function.
Increased Surgical and Anaesthetic Risk: The effects of obesity on the heart and lungs have serious consequences during anaesthesia. Cardiac arrest and poor circulation of oxygenated blood to the tissues can occur. Many of the anaesthetics are taken up by fat, so an overweight animal will take longer to come out of anaesthesia because the anaesthetic must be removed from the fat by the body. Similarly, many anaesthetics are broken down by the liver. A fatty liver may not be as efficient at breaking down anaesthetics and other drugs, so again, recovery may be delayed. The fat obscures the surgical area, making the surgery technically more difficult and the procedure longer, which again increases the anaesthetic risk.
Reproductive Problems: Overweight dogs and cats tend to have more problems giving birth than dogs/cats at their optimum weight. This difficult birthing is called dystocia. Dogs/cats experiencing dystocia often need veterinary assistance to deliver their pups, and may require a caesarean section (C-section).
Decreased Immune Function and Stamina: Obesity in the dog gradually results in decreased resistance to viral and bacterial infections. Canine distemper and Salmonella infections seem to be more severe in dogs that are overweight. Not only do they have decreased immunity, but also have less endurance and stamina.
Increased Risk of Cancer: The exact link between obesity and cancers is unknown. However, obese dogs tend to have an increased risk of developing certain types of cancers, including a particular type of cancer of the urinary bladder. Also dogs that are obese at one year of age usually have a greater risk of developing mammary tumours.
Management and Prevention of Obesity in Companion Animals
Weight problems are common in dogs and cats, and can be successfully managed through changes in food or a nutrition program. Combining a change in nutrition with increased exercise is the most effective way of achieving a healthy weight. There are basically three aspects to managing obesity in companion animals:
Weight loss in the overweight animals;
Prevention of weight gain;
Decreasing weight regain after weight loss.
These can be achieved through following feeding regime such as:
Providing less feed than earlier;
Feeding foods high in protein and fat and low in carbohydrate;
Feeding small portions at intervals rather than continuous free access/free choice;
Increasing activity/exercise of the animal.
Besides managing obesity, preventing obesity is of great importance as it is easier to avoid obesity than lose weight. Pets should have a nutritional assessment - including weighing, body condition score and muscle mass score at every veterinary visit to check for routine health issues and obesity. Feeding treats, table scraps and snacks increases the risk of obesity, so these should be strictly avoided in the diet of companion animals in order to help them avoid gaining those harmful pounds on them.
By Ankita, Shashi Kumari, Vikram, Dinesh Kumar and Punita Kumari
Ankita and Dinesh Kumar are PhD Scholars from AN Division, IVRI, Izatnagar. Shashi Kumari and Vikram are veterinary medical officers, UP Government.