(Merck) Estrumate is used as a luteolytic agent in cattle. The luteolytic action of Estrumate can be utilized to manipulate the estrous cycle to better fit certain management practices, to terminate pregnancies resulting from mismatings, and to treat certain conditions associated with prolonged luteal function. For intramuscular use in beef and dairy cattle. Estrumate is supplied at a concentration of 250 mcg cloprostenol per ml. Cloprostenol sodium.