Does your dog have soft stools or are they firm? I know you said your Vet suggested you feed her a grain inclusive food, but I believe Solid Gold Hund-n-Flocken dry food which you said you were feeding her, is grain inclusive. You also mentioned you were feeding wet food, which I know if I give any of my dogs just a small amount on their kibbles, my Pug who had anal gland problems in the past would have soft stools. I know longer let him have any.
Anyways, usually it is high fiber diet that you want when a dog is suffering from anal gland issues. Earthborn has a grain inclusive food with 8.5% to 10% fiber depending what protein source you choose. It is their Unrefined Ancient Grains and Superfood line. I personally have not tried this dog food, but a friend has and her dog is doing well on it. It comes in turkey, rabbit, salmon, and I think they recently came out with lamb. If you do switch to any dog food, it must be done slowly to avoid any gastric upset. Maybe call your Vet and ask him/her about the fiber.
18 hours, 40 minutes ago
