Leviticus 27:26-27

26But a afirstborn of animals, which as a firstborn belongs to the Lord, no man may dedicate; whether ox or sheep, it is the Lord’s. 27And if it is an unclean animal, then he shall buy it back at the valuation, band add a fifth to it; or, if it is not redeemed, it shall be sold at the valuation.

Copyright information for ESV