Ridgeback reacts to fish-based sensitive stomach food

If your dog has had a bad reaction to every fish-based sensitive stomach food you've tried, that's actually a useful signal — it points away from the protein source being the fix and toward something else going on, whether that's a broader protein sensitivity, an additive in those formulas, or a gut that needs a genuinely stripped-back ingredient list. Sensitive stomach issues in dogs usually fall into a few categories: food intolerance, ingredient sensitivity, or a digestive system that just works better on simpler food — and working out which one applies is the key to finding something that sticks. To help you find the right direction, can you tell me your dog's breed and age, exactly what symptoms you're seeing (loose stools, vomiting, gas, or something else), and what you've already tried?

That history is really telling. The fact that he was stable on chicken for a long time, then reacted consistently across three different fish-based foods, makes me wonder whether the fish proteins themselves are genuinely better for him, or whether those particular formulas share something else — additives, thickeners, or high omega oils — that his gut is objecting to. Mucus in the stools specifically suggests some gut lining irritation, which often responds well to a very simple, low-ingredient food rather than just a protein swap. Before I point you somewhere, a quick question: did the vet confirm the chicken sensitivity through an elimination trial, or was it more of an educated guess based on symptoms?

That's a helpful distinction — the skin improvement when removing chicken does suggest some sensitivity there, so I wouldn't rush back to chicken. But the stomach issues getting worse on fish points to his digestive system struggling with those specific formulas rather than fish being the answer. For a 6-year-old Ridgeback with a reactive gut, I'd want something with a single novel protein he hasn't had much exposure to, very few ingredients, and no unnecessary additives. My recommendation is Forthglade Complete Grain Free Turkey with Butternut Squash and Veg — the wet tray format. Turkey is a lean, easy-to-digest protein that's genuinely novel for most dogs who've been cycling through chicken and fish, the ingredient list is short and clean, and the wet format is gentler on an irritated gut than dry kibble. It's also free from artificial preservatives and fillers that commonly appear in sensitive stomach ranges. For a Ridgeback his size you'd be looking at around 3-4 trays a day, so it's worth buying a mixed pack first to see how he tolerates it before committing to a larger order.

Given that the current food is actively causing problems, you can transition a bit faster than the usual 7-10 day rule — but I still wouldn't go cold turkey overnight. A 4-5 day transition works well here: start with around 75% current food and 25% new, then flip to roughly half and half by day two or three, then move fully across. Watch the stool consistency as you go — if things improve during the transition that's a good sign, and if you see the mucus reducing by days 3-4 you'll know the turkey is sitting better with him. Keep a simple note of what you're feeding and what you're seeing; if the issues persist after a full two weeks on the turkey alone, that's the point to go back to the vet with a clearer picture and consider a proper elimination diet.

Good plan. The Forthglade turkey trays are widely available on Amazon UK — search for Forthglade Complete Grain Free Turkey Adult and the multipack options will come up. Give it a full two weeks on the new food before making any judgement, and do check back if things don't settle — sometimes it takes one more tweak, like adding a plain probiotic supplement, but let the food do the work first. Hope he's more comfortable very soon.