Pathological changes and clinical use of the measurement of serum/plasma concentrations of insulin-like growth factor type 1 (IGF-1) in horses, dogs and cats

The biological effects of the growth hormone are in part mediated by the release of insulin-like growth factor type 1 (IGF-1) by the liver but also from other non-hepatic tissues. As opposite as GH, IGF-1 is not release in an episodic manner, is stable in the bloodstream and has a long biological half-life. As a consequence, the measurement of serum IGF-1 is an indirect way to measure GH. The present article reviews the alterations in serum IGF-1 concentrations in veterinary medicine, focused mainly in the diagnosis and prognosis of liver, heart, musculoskeletal, endocrine diseases and tumors. Some applications of the measurements of serum IGF-1 concentrations in sport horses are also provided.