Chapter 28 Diseases of the Endocrine System
The endocrine glands and hormones in birds are similar to those found in mammals (Box 28-1). The glands release hormones into the circulation. These hormones activate a target organ to produce changes within the body. As in mammals, there is a hypothalamohypophysial axis composed of the hypothalamus and the pituitary gland. Releasing hormones are produced in the hypothalamus that are carried by the portal circulation to the anterior pituitary, where they stimulate the release of the appropriate stimulating hormone into the general circulation. Stimulating hormones released from the anterior pituitary (the adenohypophysis) include follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone, prolactin, growth hormone, and adrenocorticotropic hormone. The posterior pituitary (the neurohypophysis) releases arginine vasotocin (AVT) and mesotocin (MT).
