Leviticus 27:26
‘However, the firstborn among animals, which as a firstborn belongs to the Lord, no man may consecrate, whether an ox or a sheep. It is [already] the Lord’s.
Exodus 13:2
“Sanctify to Me [that is, set apart for My purpose] every firstborn, the first offspring of every womb among the children of Israel, both of man and of animal; it is Mine.”
Exodus 13:12-13
you shall set apart and dedicate to the Lord all that first opens the womb. All the firstborn males of your livestock shall be the Lord’s.
Exodus 22:30
You shall do the same with your oxen and with your sheep. It shall be with its mother for seven days; on the eighth day you shall give it [as an offering] to Me.
Numbers 18:17
But the firstborn of a cow or of a sheep or of a goat you shall not redeem; they are holy [and belong to the Lord]. You shall sprinkle their blood on the altar and shall offer up their fat in smoke as an offering by fire, for a sweet and soothing aroma to the Lord.
Deuteronomy 15:19
“You shall consecrate (set apart) to the Lord your God all the firstborn males that are born of your herd and flock. You shall not work with the firstborn of your herd, nor shear the firstborn of your flock.