Leviticus 22:26-30

And the LORD spake unto Moses, saying,

When a bullock, or a sheep, or a goat, is brought forth, then it shall be seven days under the dam; and from the eighth day and thenceforth it shall be accepted for an offering made by fire unto the LORD.

And whether it be cow or ewe, ye shall not kill it and her young both in one day.

And when ye will offer a sacrifice of thanksgiving unto the LORD, offer it at your own will.

On the same day it shall be eaten up; ye shall leave none of it until the morrow: I am the LORD.