Not sure who does this, so advice to those who don't.
Feed them raw meat and raw bones they can crack and digest.
Barf diet recipes for dogs.
We find it so much cheaper than the good dry food, fast boil a bit of veg so it doesn't deteriorate in the fridge or freezer, add the recommended amount of raw meat, and watch your dog blossom. I takes 30 minutes tops every few days.
Local suppliers should be easy to find.