The creature that guides a person does not define who that person is, it simply chooses to be with them. Therefore, no one can choose their own animal guide. It would offend a guide if its identity was revealed to others. Being in touch with one's animal guide is what Carl Jung thought he invented when he came up with his active imagination technique in 1932. In 2371, Chakotay helped Janeway contact her animal guide during a vision quest which turned out to be a tokay gecko. B'Elanna Torres was the only person Chakotay knew who actually tried to kill her animal guide. (VOY: "The Cloud")