Hiya
I think heart is counted as muscle meat as opposed to organ meat, Obi loves lamb hearts and gets them a couple of times a week, usually with a chicken quarter or whatever.
Liver and kidneys he gets a portion of each a week, but I've found he doesn't like the texture much, so he has them mixed with canned fish, which seems to make them more appealing
It varies as to the size of the packets they come in, but he'll usually have 2 lamb kidneys and a small pot of chicken livers, or half a packet of lamb/pork liver. I haven't got any handy as I need to go shopping so not sure of the weight of the packets
I know what you mean about the expense, I think some peole find it considerably cheaper if they have the right contacts who supply off cuts and bony bits free or at much reduced price, which I don't either.
All of my meat etc comes from the supermarket or butcher, so is more expensive, although ask around at butchers as mine will save me lamb breast which is cheap but I find hard to buy in supermarkets as people don't like it much
Like you I find that the cost is offset by the fact that it really is worth it, Obi can't tolerate any commercial dry or wet foods, and his good health is the most important thing to me
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