Hi, I'm new here and found this site on a random search. I have a 5 month old lab puppy that is being fed a large breed puppy food. I also have a six year old mastiff and he's on a basic adult food. It's become a nuisance to go to two different stores and buy two 20lb. bags. I've always owned giant breeds (mastiffs & danes) so this is my first time ever feeding puppy food. My question is would it be ok to switch my puppy to an adult food as long as it's a good quality? This way I'd only have to go to one store and could get a 40/50 lb bag instead of two 20's.