There are eight grades of beef: prime, choice,
select, standard, commercial, utility, cutter, and canner. The first
three are the ones usually seen in stores. Standard and commercial are
usually sold as ungraded or "store brand". The last three are rarely
sold for human consumption and usually used for processed meats, ground
beef, and most frequently: pet food. So yes, it's entirely possible
(but unlikely) that you are eating the same meat as your dog, which
doesn't really mean much. It's just ground up meat. If it won't kill
your dog, it isn't going to kill you.