I don't recall teams rotating more than DL. Other than different packages. But I could be wrong.
Just out of curiosity, I looked at Iowa as they had a similar game.
They had five guys play all 58 defensive snaps (we also had five play all 70 snaps). Both teams had two CBs, two Safeties and an ILB play every snap. Their other ILB played the next-most snaps.
So I'd say it's not that uncommon.