Numbers 18:15

Every first issue of the womb of all flesh, whether man or animal, which they offer to the Lord, shall be yours; nevertheless the firstborn of man you shall surely redeem, and the firstborn of unclean animals you shall redeem.

Exodus 34:20

You shall redeem with a lamb the first offspring from a donkey; and if you do not redeem it, then you shall break its neck. You shall redeem all the firstborn of your sons. None shall appear before Me empty-handed.

Exodus 13:2

Sanctify to Me every firstborn, the first offspring of every womb among the sons of Israel, both of man and beast; it belongs to Me.”

Exodus 13:12-13

you shall devote to the Lord the first offspring of every womb, and the first offspring of every beast that you own; the males belong to the Lord.

Exodus 22:29

You shall not delay the offering from your harvest and your vintage. The firstborn of your sons you shall give to Me.

Leviticus 27:26-27

However, a firstborn among animals, which as a firstborn belongs to the Lord, no man may consecrate it; whether ox or sheep, it is the Lord’s.

Numbers 3:13

For all the firstborn are Mine; on the day that I struck down all the firstborn in the land of Egypt, I sanctified to Myself all the firstborn in Israel, from man to beast. They shall be Mine; I am the Lord.”

Numbers 3:46

For the ransom of the 273 of the firstborn of the sons of Israel who are in excess beyond the Levites,

Treasury of Scripture Knowledge

Summary

Every thing that openeth the matrix in all flesh, which they bring unto the LORD, whether it be of men or beasts, shall be thine: nevertheless the firstborn of man shalt thou surely redeem, and the firstling of unclean beasts shalt thou redeem.

General references

Bible References

The firstborn

Exodus 13:13
But every first offspring of a donkey you shall redeem with a lamb, but if you do not redeem it, then you shall break its neck; and every firstborn of man among your sons you shall redeem.
Exodus 34:20
You shall redeem with a lamb the first offspring from a donkey; and if you do not redeem it, then you shall break its neck. You shall redeem all the firstborn of your sons. None shall appear before Me empty-handed.
Leviticus 27:27
But if it is among the unclean animals, then he shall redeem it according to your valuation and add to it one-fifth of it; and if it is not redeemed, then it shall be sold according to your valuation.

General references

Numbers 3:15
Number the sons of Levi by their fathers’ households, by their families; every male from a month old and upward you shall number.”