If it just says 24% chick starter it is ok although I've heard too high of a protein can cause leg problems. I started mine on a 20% chick starter and they are wonderful. You also supposedly need to add niacin to their diet if not feeding a duck feed.
I feed my ducks the Chick Starter, same as the baby chicks and I have never had a problem. But mine also get clover and grass. So I guess it just all depends.