Recognizing Obesity in Dogs & Cats as a Disease

Examining the Endocrine and Secretory Function of Fat Cells

Jul 26, 2009

Canine and feline fat cells, or adipocytes, produce hormones known as adipokines which decrease the metabolic rate and inhibit appetite suppression in obese dogs and cats

Obesity is well recognized as the most common nutritional disorder seen in both dogs and cats. Canine and feline obesity is known to have adverse effects on numerous body systems.

Obesity in Dogs and Cats is Now Recognized as a Disease

It was once thought that canine and feline obesity resulted from overfeeding and lack of adequate exercise alone. However, It is becoming increasingly recognized that obesity is a disease in and of itself. Fat cells are now recognized as having an endocrine and secretory function which produces hormones that have effects on various organs. Besides acting to decrease the overall metabolic rate of the obese dog and cat, these hormones also function to suppress the appetite suppression seen in normal non-obese animals. Thus, overweight dogs and cats are not only unable to metabolize energy as quickly as lean animals, but are also more likely to overeat.

Adipokines – Hormones Produced by Fat Cells

Fat cells, scientifically known as adipocytes, produce a number of hormones which are collectively known as adipokines. Numerous types of adipokines have been identified and include:

Effects of Adipokines in the Obese Dog or Cat

Adipokines play a key role in regulating the energy balance in dogs and cats. These hormones also appear to play a key role in mediating inflammation, in appetite satiation (promoting meal termination) and satiety (regulating meal frequency), and in insulin resistance.

In basic terms, these hormones act to decrease the metabolic rate in dogs and cats which are already overweight or obese. This decrease in metabolic rate is likely to lead to additional weight gain and difficulty in losing weight.

In addition, overweight or obese dogs and cats are likely to experience even more pain when inflammatory conditions, such as arthritis, become a problem. This increase in pain associated with arthritis in obese dogs and cats is not only a result of the increased weight putting additional strain on the joints, but is also associated with adipokines exerting their own inflammatory effects on the joints.

Diabetes mellitus is also more likely in overweight or obese dogs and cats than in lean or normal weight animals. Furthermore, regulation of diabetes mellitus may be more difficult in these pets due to the effects of adipokines on insulin regulation. Obesity is one of the most common predisposing factors in insulin resistance and this is a result of the action of the adipokines produced in the fat cells of obese pets.

Though it should be obvious that excessive food intake and inadequate exercise plays a part in the development and maintenance of obesity in dogs and cats, pet owners also need to be aware that weight loss and disease control in obese animals can become very challenging because of the effects of the fat cells themselves and the hormones these fat cells produce.

NGF gene expression and secretion by canine adipocytes in primary culture: upregulation by the inflammatory mediators LPS and TNFalpha. V H Ryan et al. Hormone Metabolic Research. December 2008;40(12):861-8.

Adipokine gene expression in dog adipose tissues and dog white adipocytes differentiated in primary culture. I Eisele et al. Hormone Metabolic Research. August 2005;37(8):474-81.

Feline adiponectin: molecular structures and plasma concentrations in obese cats. Katsumi Ishioka et al. Journal of Veterinary Medical Science. February 2009;71(2):189-94.

The copyright of the article Recognizing Obesity in Dogs & Cats as a Disease in Pet Nutrition is owned by Lorie Huston. Permission to republish Recognizing Obesity in Dogs & Cats as a Disease in print or online must be granted by the author in writing.