Numbers 18:15-17

Young's Literal Translation

¹⁵ every one opening a womb of all flesh which they bring near to Jehovah, among man and among beast, is thine; only, thou dost certainly ransom the first-born of man, and the firstling of the unclean beast thou dost ransom.

¹⁶ `And their ransomed ones from a son of a month, thou dost ransom with thy valuation, of silver, five shekels, by the shekel of the sanctuary, twenty gerahs it [is].

¹⁷ `Only, the firstling of a cow, or the firstling of a sheep, or the firstling of a goat, thou dost not ransom, holy they [are]: their blood thou dost sprinkle on the altar, and of their fat thou makest perfume, a fire-offering of sweet fragrance to Jehovah,