Iodine, necessary to ensure that the thyroid gland functions properly, is commonly found in fish and iodized salt; your dog consumes it in commercial dog food's potassium iodide, potassium iodate, sodium iodide or calcium iodide. Your dog needs at least 0.7 milligrams of iodine per pound of dry food every day. If he doesn't consume enough iodine, a deficiency may cause hypothyroidism.
Signs of Hypothyroidism
Hypothyroidism is the most common hormonal disorder in dogs, commonly affecting spayed and neutered adult dogs between 4 to 10 years old. Low iodine can cause symptoms including poor growth, hair loss, lethargy, depression and weight gain without increase in food or appetite. You may notice behavioral changes in your dog, constipation, diarrhea and overall weakness. More serious signs of hypothyroidism include an intolerance to cold temperatures, a slowed heart rate (bradycardia) and chronic skin disorders. Adult dogs may experience infertility and breeding problems.
Causes and Diagnosing
Although most dog food contains enough iodine for your dog, he may not be able to consume the amount of iodine he needs if he is not eating properly. If you think your dog may have an iodine deficiency, your vet will perform a few tests. A complete blood count is the first test your vet will perform. He'll probably also do a biochemical profile, urinalysis and thyroid-stimulating hormone test. After examining your dog and the results of testing, he will be able to determine if your dog has an iodine deficiency.
Hypothyroidism is easily treated, but the treatment involves a daily dose of synthietic thyroxine. Your vet will want to regularly monitor your dog's iodine levels to determine if the dog will need the treatment for the rest of his life or if the treatment will be temporary.
Foremost, offer a well-balanced diet with a well-rounded dog food. If your dog is at risk of an iodine deficiency, offer a premium dog food whose first-listed ingredient is fish, because fish is high in iodine. In addition to a premium dry dog food, you can supplement your dog's diet -- only with your vet's OK -- with others foods that are rich in iodine, such as leafy, green vegetables, turkey breast, eggs and cod. Sprinkling the dog food with a pinch of iodized salt can help prevent a deficiency, but you do not want to oversalt his food.
By Whitney Lowell
About the Author
Whitney Lowell has been writing online since 2007. She writes for a variety of online publications and across a wide range of topics and niches. She has experience with animal rescue, dog training, pet health and breeding reptiles.