Dogs and cats share many similarities, but not in the case of thyroid disease. While cats are typically affected by overactive thyroid glands (hyperthyroidism), dogs suffer from a lack of thyroid hormones (hypothyroidism). People, on the other hand, can be affected by both underactive and overactive thyroid glands. The thyroid glands form the shape of a butterfly and are situated in the neck on either side of the trachea (windpipe). The glands are part of the body’s endocrine system, and are therefore important in the production of hormones. The glands are controlled, in turn, by yet another hormone released from the pituitary gland which sits beneath the brain.

With an understanding of the many important physiologic functions of thyroid hormones, one can easily understand the many problems that occur when the hormone levels become unbalanced. The main function of the thyroid gland is to regulate the body’s metabolism, or how it uses energy. It plays a role in regulating heat rate, breathing, body weight, the nervous system, and body temperature.

When too little thyroid hormone is produced, dogs will exhibit symptoms such as:

·       Lethargy

·       Dull hair coat and hair loss

·       Weight gain

·       Scaly skin and skin infections

·       Mental dullness

Hypothyroidism is seen more commonly in medium and large sized dogs. Certain dog breeds such as Golden Retrievers, Doberman Pinschers, Great Danes, Boxers, Dachshunds, miniature Schnauzers and Irish Setters are predisposed.

When too much thyroid hormone is produced, cats will exhibit symptoms such as

·       Weight loss

·       Increased appetite

·       Increased thirst

·       Vomiting and diarrhea

·       High blood pressure

Hyperthyroidism is typically diagnosed in senior cats with an average age at diagnosis of 13 years. Both hypothyroidism and hyperthyroidism are diagnosed based upon blood test results. Dogs with hypothyroidism are managed with medication. Once treatment has been initiated, periodic blood tests are necessary to determine if any medication adjustments are needed.

When it comes to treating hyperthyroid cats, more options are available. Surgery to remove the benign thyroid tumors is still an option, but not commonly pursued. Cat owners are more likely to choose medication or radiotherapy. Medication must be given for the remainder of the cat’s life and, like dogs, periodic blood work will be needed to monitor thyroid hormone levels. Treatment with radioactive iodine (Iodine 131) requires an initial evaluation to determine the cat’s candidacy for the procedure, a stay of 3-4 days at a veterinary specialty facility, and special precautions once the cat returns home.

Both feline hyperthyroidism and canine hypothyroidism are easily diagnosed and readily manageable. If you notice your pet displaying the typical symptoms of either condition, contact your veterinarian for a consult appointment and blood testing.

Microchips

The American Veterinary Medical Association and the American Animal Hospital Association sponsor national “Check the Chip” day every August. Studies have shown that dogs, which become lost, are 30 percent more likely to be reunited with their family if they have a microchip. Cats with microchips are almost 40 percent more likely to be returned to their home. Although microchips do not locate lost pets like a GPS collar, they are important in proving pet ownership and providing identification if collars and I.D. tags are lost.

For more information, go to www.avma.org/checkthechip

If you need help determining where your pet is registered, go to www.petmicrochiplookup.org