Endocrine diseases in animals.

Several endocrine disorders that affect humans also occur as endocrinopathies in companion animals. Spontaneous endocrine disorders in animals may provide valuable information for their counterparts in human endocrinology. For example, the discovery of progesterone-induced growth hormone production in the mammary gland of dogs may have important consequences for understanding the pathogenesis of breast cancer in women. In addition, the majority of diabetic cats have a type of diabetes mellitus that closely resembles type 2 diabetes mellitus in humans and therefore may serve as an animal model for this disease in humans. This review describes several endocrine diseases in companion animals that are quite similar to those in humans and emphasizes their usefulness as spontaneous animal models for human endocrine disorders.