Hilchos Issurei Mizbeiach 4:4

An animal or bird is disqualified for the altar by being designated for idolatry when the idolatrous priests actually do something with it, such as shearing it or working it for the purpose of idolatry. It is not considered designated for idolatry through words alone because there’s no consecration vis-à-vis idolatry.

Hilchos Issurei Mizbeiach 4:5

An animal that had relations with a human, or that a human had relations with, becomes prohibited for the altar regardless of whether it belongs to the party with whom it had relations or to someone else, and regardless of whether the relations were coerced or voluntarily, intentional or unintentional, before the animal was consecrated or after. An animal designated for idolatry, however, is disqualified if it belongs to the one who designated it and he designated it before he consecrated it. If someone designated an animal belonging to someone else – or even his own animal after consecrating it – it remains permitted for the altar. This is because one can’t designate another person’s property for idolatry.