Bechoros 6:12-7:1

Bechoros 6:12

One may not slaughter a firstborn animal because of the following blemishes, neither as sacrifices nor for food: white spots and water in the eye that are only temporary; if its back teeth are defective but not removed; various types of boils and warts; if the animal is old, sick or smells bad; if a sexual sin was committed with it or it killed a person but there’s only one witness, or its owners are the witnesses; if the animal is of indeterminate gender (a tumtum) or a hermaphrodite (an androginos). Rabbi Yishmael says there is no greater blemish than if an animal is an adroginos but the Sages say that such an animal is not a firstborn (which must be a male) so it may be shorn and worked.

Bechoros 7:1

The blemishes that disqualify an animal also render a kohein unable to serve regardless of whether they are permanent or temporary. There are additional blemishes that apply exclusively to people, including a variety of misshapen heads (wedge-shaped, hammer-shaped, etc.). Rabbi Yehuda says that a hunchbacked kohein is fit to serve but the Sages disagree.