Heart isn’t an organ, it’s a muscle, so there’s really no issue with that. The only problem I see with offering the large amount of organs you have to such small dogs is hat raw organs are high in various vitamins and minerals that can cause toxicitiy when fed too much of. However, you can freeze them into serving size portions and offer once a week or so as a special meal, or dry them and offer a couple bites a day as a treat. The dried organs would still need to be frozen (or shared with friends) as that amount of meat would go bad before it would be used.
What kind of hunting dogs do you have? I would love to see some pictures! And where do you live that you hunt deer? My family’s got a hunting camp up in Michigan that a few of the guys stay at for several weeks each year. It’s amazing up there! And love me a good Bambi :p
