Exodus 22:30
Likewise shalt thou do with thine oxen and with thy sheep; seven days it shall be with his dam; on the eighth day thou shalt give it to me.
Leviticus 22:27
When a bullock or a sheep or a goat is born, then it shall be seven days under the dam; and from the eighth day and thenceforth it shall be accepted for an offering on fire unto the LORD.
Deuteronomy 15:19
All the firstborn males that come of thy herd and of thy flock thou shalt sanctify unto the LORD thy God; thou shalt do no work with the firstborn of thy bullock nor shear the firstborn of thy sheep.
Exodus 13:12
that thou shalt set apart unto the LORD all that opens the womb and in the same manner every firstborn that opens the wombs of thy animals; the males shall be the LORD's.
Leviticus 12:3
And in the eighth day the flesh of his foreskin shall be circumcised.