The purpose of the cranberry juice was so that he would drink more fluids while on metacam since I decided NOT to do the acidifying S/D or equivalent. And to increase his fluids, since he does not drink much as his food is home cooked plus he gets distracted by his reflection in the water bowl (I'm not kidding, he really likes to admire himself

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I am aware that fat is necessary in a diet but having home cooked for my dogs for 10 years I am strongly opposed to commercial foods except when in a pinch

Teddy violently threw up that can of S/D and I said I was not doing it until I heard from the vet nutritionist. It is so loaded with sodium that i have a big problem with it, in addition to the garbage fats. He not only threw up but he was hiccuping and shaking after because he was so upset about it.
Whatever is in that can can be replicated by home cooked nutritious foods. I did that with Hill's L/D for my MVD dog with excellent results -- I'm just frustrated waiting and trying for months to get to the bottom of this and having every test come up normal.
If at the end of the day I have to take a yes ma'am approach and try this for the stones, I will, but I will be very cranky about it