Actually, the gizzard is a very fibrous, tough muscle that is used in digestion. FloppyDog might be thinking of "giblets" which is a term that often means all the organs you typically get when you buy a whole bird...it usually comes in a little bag and inclues includes the liver, gizzard and heart.
The beauty of raw is that there is no real right or wrong in terms of when to feed. The main thing you need to get right is the proportions of meat:bone
rgan. You want to feed about 70% meat, 15% bone and 15% organ/offal (most of which is liver; it's the largest organ in the body), give or take. It doesn't really matter if you feed only meat, or mostly bone in one meal...if you're going for a prey model diet you simply aim to ensure that the entire week's (or even two week's) meals to add up to one prey item.
The gizzards are basically muscle...I would count those as "meat", personally...my dogs rarely get them because they're so small and it takes a lot to make a meal, but if I have a few handy I'll use them to "top up" a smaller meal, or just give as a treat. One could argue that the heart is also muscle meat, but it does contain higher amounts of some nutrients than other muscle meats, and in my experience is too rich for some dogs to eat in large quantities.
The diet you have for your dog now is a great starting point, but you should probably increase the organ intake and variety by adding things like tripe (Tripett canned is what we use, it's very hard to find raw), beef and chicken hearts, pork and beef kidneys (back-on chicken legs usually have the kidneys in them) and, well, pretty much any old bit of food you can find (we've snagged things like tails, trotters, fish heads, ears...every bit of the prey has nutritional value and can be given as "offal" . The necks are great and the eggs are fine a couple times a week. The other thing I would look into is adding some variety to the protein source. I see you've got chicken meat and beef liver...good start...you might consider adding cheap cuts of pork like shoulder/picnic, and beef (we use tongue that we get very cheap from the butcher or ground beef most of the time...beef is definitely more pricey...that frozen flank steak would be a great treat!). It's hard to say without seeing the food, but the diet might be a bit bone-heavy. Try a few meals a week of just meat (pork shoulder and beef tongue are top on my list for these meals, price-wise) to up the meat portion of the diet.
The recreational bones are wonderful...if you've got a dog who doesn't find large amounts of marrow too rich (mine all get explosive poops if they get marrow bones!) and who isn't a really hard chewer. One of my dogs can't have heavy bones like large legs and marrow bones; she chips teeth very easily. The others are ok. Just watch the teeth.
Hope that helps!
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