any substance possessing the biological activity of oestrus-producing hormones, either occurring naturally or prepared synthetically

Chemical compounds found in animals as hormones but also found in the leaves of legumes. When found in plants they can reduce the fertility of ewes. The particular compound involved appears to be formononetin. Some cultivars of subterranean clover have very high formononetin cultivars Yarloop, Dwalganup and Dinninup. Others have very little cultivars Daliak, Seaton Park.

Female sex hormones, a group of hormones that are produced mainly by the ovaries. They are essential for normal sexual development (the breasts, vagina, womb, broad hips and rounded figure etc.) and for the reproductive system (make the cervical mucus amenable to the entry of sperm, prepare the endometrium and regulate the production of FSH and LH).

See estrogens