I don't live in Denver but I have a couple of suggestions that may help. I don't know if you are looking for a butcher that runs a clean establishment or one that caters to dog owners. If you're looking for a clean butcher check with your local health dept for the one with the fewest or no infractions. If you are looking for one that caters to the canine crowd, check with a holistic vet and find out who they would recommend. I hope this helps.
Pam, Mom to
Thor-male brindle 05/24/01
Arabella-female brindle 12/19/06
Star-at the bridge 05/13/98-11/22/08