You are not to present anything that has a defect, because it will not be accepted on your behalf. "When a man presents a fellowship sacrifice to the Lord to fulfill a vow or as a freewill offering from the herd or flock, it has to be unblemished to be acceptable; there must be no defect in it. read more.
You are not to present any [animal] to the Lord that is blind, injured, maimed, or has a running sore, festering rash, or scabs; you may not put any of them on the altar as a fire offering to the Lord. You may sacrifice as a freewill offering any animal from the herd or flock that has an elongated or stunted limb, but it is not acceptable as a vow offering. You are not to present to the Lord anything that has bruised, crushed, torn, or severed [testicles]; you must not sacrifice [them] in your land.