Leviticus 27:26-27
“‘However the firstborn among animals, which belongs to Yahweh as a firstborn, no man may dedicate, whether an ox or a sheep. It is Yahweh’s. If it is an unclean animal, then he shall buy it back according to your valuation, and shall add to it the fifth part of it; or if it isn’t redeemed, then it shall be sold according to your valuation.