Thanks for the additional info. I'm sorry about all the questions but I needed to ask them because your kitty is new to me.
I asked about the pooping because constipation/obstipation can lead to inappetence.
If your kitty is not eating and has a possible upper respiratory infection that could leave him vulnerable to producing ketones (more so if diabetes is currently not fully regulated). If the ketones aren't addressed immediately it can quickly progress to diabetic ketoacidosis which is life-threatening. It's not something that can be managed at home because the electrolytes go completely out of whack and veterinary intervention is needed to correct the imbalances, along with aggressive insulin treatment, fluid therapy and getting food into the kitty, possibly with some means of assisted feeding.
I don't have experience with raw feeding (Red has tagged Wendy to ask for her help on this). If the raw you're feeding isn't a complete food then that can knock the system out of kilter.
Without knowing what your kitty's blood glucose levels are doing it's impossible to suggest anything on the insulin side of things. If you let us know which meters you have then maybe one of our US members might be able to give you some pointers on how to get one of them to read properly for you.
The problems with walking/jumping could potentially be due to diabetic neuropathy (caused by damage to nerves when a cat is poorly regulated) or an electrolyte problem (e.g. low potassium levels), possibly lack of key nutrients in the food.
Eating lots but still losing weight is usually a clinical sign of poorly-regulated blood sugars (body can't properly utilise the food eaten).
@Wendy&Neko - Could sub-q fluids help?
My best suggestion to you right now is that you get hold of ketone test strips tonight (Walmart or any pharmacy should have them) and check his pee. I forgot to add the link for tips on collecting a sample earlier (sorry!). Here it is:
Tips for collecting urine samples
If the ketones are higher than trace levels then urgent veterinary support is needed (and it gives me no joy to write that: I know what it's like to have stretched finances). If the ketones and inappetence are addressed quickly it can prevent progression to DKA. Further info:
Ketones and DKA
If ketones are in the mix then treating for nausea can help the cat to start eating again. (BTW, I directed you to the nausea symptom checklist earlier because the info there is applicable to nausea in general, not just for CKD kitties. I'm sorry I didn't make that clear in my earlier post.)
Mogs
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