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Excessive Weight in Cats
Obesity is a nutritional disease which is defined by an excess of body fat. Cats that are over nourished, lack the ability to exercise, or that have a tendency to retain weight are at risk for becoming obese. Obesity can result in serious adverse health effects, such as reducing the lifespan of an affected cat, even if the cat is only moderately obese. Multiple areas of the body are affected by excess body fat, including the bones and joints, the digestive organs, and the organs responsible for breathing capacity.
Obesity usually occurs in middle-aged cats, and generally in those that are between the ages of 5 and 10. Neutered and indoor cats are at the highest risk of becoming obese, due to lack of physical activity, or changes in metabolism.
If you would like to read how obesity affects dogs, please visit this page in the PetMD health library.
Symptoms
Weight gain
Excess body fat
The inability (or unwillingness) to exercise
An above-ideal score in a body condition assessment
Causes
There are several causes of obesity. The most common cause is an imbalance between the energy intake and its usage; that is, the cat is eating more than it can possibly expend. Obesity also becomes more common in old age because of the normal decreases in a cat's ability to exercise. Unhealthy eating habits, such as high-calorie foods, an alternating diet, and frequent treats can also bring on this condition.
Other common causes include:
Hypothyroidism
Insulinoma
Hyperadrenocorticism
Neutering
Diagnosis
Obesity is diagnosed primarily by measuring a cat's body weight, or by scoring its body condition, which involves assessing its body composition. Your veterinarian will do this by examining your cat, palpating its ribs, lumbar area, tail, and head. The results are then compared to the particular breed standard that your cat best matches.
If your cat is diagnosed with obesity, it will be because it has an excess of body weight measuring approximately 10 to 15 percent. In the nine-point scoring system, cats which have a body condition score greater than seven are considered to be obese.
Treatment
Treatment for obesity is focused on weight loss and maintaining a decreased body weight for the long term. This is accomplished by reducing caloric intake and increasing your cat's exercise routine and time spent doing it. Your veterinarian will most likely have a prepared diet plan that you can use to refigure your cat's eating schedule, or will help you to create a long-term diet plan for your cat.
Diets that are rich in dietary protein and fiber, but low in fat, are typically recommended, since dietary protein stimulates metabolism and energy expenditure, along with giving the feeling of fullness, so that your cat will not feel hungry again shortly after eating. Dietary fiber, on the other hand, contains little energy but stimulates intestinal metabolism and energy use at the same time.
Increasing your cat's physical activity level is vital for treatment. For cats, the use of interactive toys, such as laser lights, is encouraged, along with games of fetch, if your cat enjoys it, and other chase and catch games.
Living and Management
Follow-up treatment for obesity includes communicating regularly with your veterinarian about the progress you are having with your cat's weight reduction program. Monthly monitoring of your cat's weight, along with a firm commitment to your cat's diet will be the establishment of a lifetime weight maintenance program, so that even after the ideal body condition score has been achieved you will feel confident that your cat is eating healthy and feeling its best.