Hi Donna,
From you post it isn’t clear to me if you your boy is on K/d because he his kidney are not working well ( kidney insufficiency?failure) or that he was placed on KD to control stone formation or both?? Does he currently have stones in his kidneys? Was the surgery to remove stones that were in the bladder and urethra or were they really in the kidneys ?
What was the stone composition?
How much K/D is he currently fed compared to the label recommendations? K/D should not be used for weight loss.
If he needs a diet for weight loss and kidney insufficiency and stone formation that looks to be a tricky combination and appears that a home cooked diet tailored to his specific problems and formulated by a veterinary nutritionist would be the best plan.
I agree with anon that you need to work through your veterinarian or seek another veterinary opinion. Personally i wouldn’t be keen to return to a grain free diet until more is understood about diet related cardiomyopathy.
