seman from animals is usually collected by stimulating the glans of your animal's [censored]. It is then collected in a condem like bag and usually frozen.
Ingesting animal seman is old news - in fact there is a cook book from Amazon that's quite a popular gag gift. It never specifically says what kind of seman they use but it is noted that most places use animals bred of collecting seman; I assume because diet plays a large factor in the taste. Some of the recipes are quite tame but the 'oyster au naturale' is just seman in oyster shells.
EDIT: Holy Gamorrean gonads, [censored] is censored? Hahahah!
Yeah if they want to eat that, fine, but I sure as hell wont. Also I once got linked to a book on amazong about cooking this stuff. Like the other guy said, yeah some people are freaky like that.