Yes.
When God killed the firstborn of the Egyptians, he decided that the firstborn of the Israelites would be set apart to be his. So God commanded his people to consecrate every firstborn male to him. He said the first son of every female animal or human in Israel belongs to him. You can never choose to dedicate a firstborn animal to God, because the firstborn already belongs to God by default.
That means the people have to give all their firstborn males over to God. You must give him the firstborn of your sons, doing the same thing you do with the firstborn among your livestock: They can only stay with their mothers for seven days, then you hand them over to God. They are to be set apart and never put to work the way others would be. This is how God decided it will be, therefore this is how it will be forever, and it can never be changed.