I have some ducks that are now close to 2 months old and I want to switch them from the chick starter I have been feeding them. I have read that they do not need as high a protein food as the chickens do, so I don't want to put them on grower mash. I can get regular chicken feed or game bird feed, both non-medicated, locally at the feed store. Which would be better? Assuming that the game bird feed is not a lot more expensive.