Institut für Physiologie, Technische Universität, München-Weihenstephan, 805 Freising, West Germany
(Received 5 September 1975)
It is known that 16-unsaturated C-19 steroids possess a smell varying between musk and urine. They are commonly defined as boar pheromones stimulating the immobilization reflex of sows before mating (Signoret & du Mesnil du Buisson, 1961; Reed, Melrose & Patterson, 1974). One of these steroids, 5α-androst-16-en-3-one, which possesses a urine-like smell, was used to study pheromone physiology in boars. This compound is synthesized in the testes, distributed by the blood, stored in fatty tissue and salivary glands and transferred by a saliva foam to the female animal (Claus, Hoffmann & Karg, 1971; Claus, 1975 a). So far there is no information concerning the presence of 16-unsaturated steroids in other mammals, but our own measurements (R. Claus & W. Alsing, unpublished) have revealed negative results in the fatty tissue of billy-goats, rams, stallions, bulls and roebucks.