The ovary is a bean shaped organ which varies in size with season. During the winter, most mares have small, hard ovaries. As the light increases, there is an increase in connective tissue and small follicles and the ovary increases in size. The ovaries and follicles of the mare are the largest in the farm animal species [2-3 inches (6-8 cm) in length, 1-1.5 inches (3-4 cm) in height, 70-80 gm]. The ovary has both an exocrine function (produces eggs) and an endocrine function (produced hormones).