No, Gatsby has been eating s/d dry and c/d canned prescription food since early August because of his urinary tract issues. He has his own room, so he doesn't have any access to the other cats' food, and they don't have any access to his. Kiri and the others eat Pinnacle, Merrick, Instinct, and Homestyle. So I don't think that food is the culprit.
So far Gatsby isn't having serious problems. I suppose it's possible that his current antibiotic is causing an upset tummy, but he'd been taking it for several days without any trouble.
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