Oestrogenic activity in legumes

SUMMARY The teat-length increases observed in wether lambs grazing pure legumes have been compared directly with the oestrogenic activity demonstrated in mice fed samples of these pastures. In the case of red clover, the mouse assay gives a good indication of the oestrogenic effect to be expected in the wethers. There was no such correlation when samples of clover and lucerne were tested. These were much more active in the wethers than would have been anticipated from the mouse assay, where lucerne and white clover appeared almost entirely lacking in oestrogenic activity.