For every firstborn male in Israel is Mine, both man and beast. I set them apart for Myself on the day I struck down all the firstborn in the land of Egypt.
KJV
For all the firstborn of the children of Israel [are] mine, [both] man and beast: on the day that I smote every firstborn in the land of Egypt I sanctified them for myself.
ASV
For all the first-born among the children of Israel are mine, both man and beast: on the day that I smote all the first-born in the land of Egypt I sanctified them for myself.