The most clearly defined neurologic disease associated with canine hypothyroidism is hypothyroid polyneuropathy, which causes generalized weakness. The disease may or may not be associated with clinical signs of reproductive dysfunction. Hypothyroidism can effect hemostasis, or the ability to control bleeding. Hypothryoidism can cause slowing of the heart and cardiac arrhythmias. The most common biochemical abnormality in hypothyroid dogs is hyperlipidemia, or high serum lipid levels.
Numerous drugs can depress thyroid hormone concentrations.
The most significant outcome was the establishment of a practical approach to diagnosing and monitoring hypothyroidism. Out of this was born the OFA thyroid screening panel and certification registry. After this initial database is developed, testing depends on whether the dog is a pet, performance or breeding dog. Breeding and Performance Dogs . In normal dogs, these tests should be repeated annually.