Geeldikkop: preservation of toxic material.

Wilted Tribulus terrestris plants were harvested from a camp in which geeldikkop had just previously broken out. The plants were treated in various ways in an attempt to preserve their toxicity. The only successful method of preservation found was rapid freezing of harvested material. Three kg of plants were kept frozen for six weeks and then dosed via rumen fistula to a sheep which subsequently developed characteristic symptoms and lesions of geeldikkop.