Anestrus and spontaneous galactorrhea in a hypothyroid bitch.

A bitch, with a history of prolonged postweaning galactorrhea, dermatitis and lethargy, was examined because of an extended anestrus and the development of spontaneous galactorrhea. A diagnosis of hypothyroidism was made based on the history, a subnormal T(4) level and the response to a therapeutic trial of thyroxine replacement. A possible pathogenesis for the spontaneous galactorrhea is discussed.