Copper Limits for Dogs With Liver Disease: Milligrams per Kilo by Dog Weight and Low-Copper Foods to Buy in Ontario

Therapeutic low-copper diets for dogs with copper-associated liver disease generally supply under 5 mg of copper per kilogram of dry matter — roughly 0.5 mg daily for a 5 kg dog and about 2.3 mg for a 40 kg dog. Ordinary adult kibble often runs three to five times higher. Diagnosis and diet selection belong with your veterinarian.

That gap is the whole story. A dog whose liver biopsy came back with elevated copper isn't harmed by one meal; it's harmed by years of a slightly-too-generous mineral premix. If your vet has flagged copper, the practical job is reading guaranteed analysis panels and ingredient decks properly before you commit to a bag — and knowing which shelves in the dry dog food aisle are worth a second look versus which ones you can skip immediately.

What the standards say about copper in dog food

The AAFCO Dog Food Nutrient Profiles set a copper minimum of 7.3 mg per kilogram of dry matter for adult maintenance and 12.4 mg/kg DM for growth and reproduction, with no maximum currently established for dogs. The National Research Council's safe upper limit sits far higher at 250 mg/kg DM — a ceiling written for healthy livers, not damaged ones.

Two details matter more than the numbers themselves. First, in 1997 AAFCO stopped recognizing copper oxide as a valid source because it's so poorly absorbed, pushing manufacturers toward highly bioavailable forms such as copper sulfate, copper proteinate, and copper amino acid chelate. Second, the minimum is a floor, and most manufacturers formulate comfortably above it — commercial adult diets commonly test between 12 and 30 mg/kg DM.

Veterinary hepatology specialists raised this publicly in a 2021 letter published in the Journal of the American Veterinary Medical Association, asking AAFCO to reconsider copper guidelines after decades of rising hepatic copper concentrations in biopsy samples. Work indexed through 2024 on NCBI/PubMed continues to document copper accumulation in breeds with no known genetic mutation, which is why the conversation shifted from "Bedlington problem" to "diet formulation question." The American Veterinary Medical Association and your own vet remain the right authorities on whether your dog needs restriction at all.

For reference on what a diagnosis actually looks like: quantitative liver copper below roughly 400 µg per gram dry weight is considered normal, values above 600 µg/g are abnormal, and concentrations exceeding 1,000–1,500 µg/g are commonly associated with active hepatitis. Bloodwork alone can't give you that number — only a biopsy can.

Daily copper intake by dog weight

Here's how dry-matter concentrations translate into actual milligrams per day, using typical adult maintenance energy needs and a kibble averaging about 3,750 kcal per kilogram. Compare the restricted column (5 mg/kg DM) against a standard diet at 20 mg/kg DM:

• 5 kg dog (≈100 g food/day, ~375 kcal) — restricted: about 0.5 mg copper daily; standard diet: about 2.0 mg
• 10 kg dog (≈150 g/day, ~630 kcal) — restricted: about 0.75 mg; standard diet: about 3.0 mg
• 20 kg dog (≈260 g/day, ~1,060 kcal) — restricted: about 1.3 mg; standard diet: about 5.2 mg
• 30 kg dog (≈350 g/day, ~1,435 kcal) — restricted: about 1.8 mg; standard diet: about 7.0 mg
• 40 kg dog (≈450 g/day, ~1,780 kcal) — restricted: about 2.3 mg; standard diet: about 9.0 mg

Those are estimates for planning conversations, not prescriptions. Activity level, neuter status, body condition score, and the caloric density of your specific bag all shift intake. Ask your veterinarian for the target your dog's biopsy or breed risk actually justifies.

What we see in the store

Copper questions arrive in one of two ways: a Labrador owner holding a discharge summary from a specialty hospital, or a Bedlington or West Highland White Terrier owner who read about the breed risk before any symptoms appeared. Both need the same thing — help decoding labels, because copper isn't listed on a guaranteed analysis panel.

Our team at Ashario Pets recommends starting with the ingredient deck rather than the marketing copy on the front of the bag. When a customer comes in with a hepatic diagnosis, we go straight to the last third of the ingredient list looking for copper sulfate or copper proteinate, then scan the protein and produce sections for liver, kidney, duck, lamb, and shellfish. Pet owners tell us they're surprised how often "beef liver" sits third or fourth in a premium formula they'd been feeding for years.

The second thing we do is phone or email the manufacturer. Typical nutrient analyses — including copper in mg/kg dry matter — exist for nearly every brand on our shelves, but they're rarely printed on packaging. Reputable Canadian companies like Open Farm, Carna4, and Canadian Naturals will send them; we've done this on a customer's behalf more than once while they waited. In our store we see far better outcomes when owners bring the manufacturer's number back to their vet instead of guessing from the ingredient panel alone.

One local wrinkle: GTA owners who walk the trails around G. Ross Lord Park often supplement with liver-based training treats because they hold a dog's attention outdoors. For a copper-restricted dog, that daily handful of dehydrated liver can quietly rival the copper in the meal itself.

Copper and liver disease questions Ontario dog owners ask

How much copper is safe for dogs with liver disease?

Most veterinary therapeutic hepatic diets are formulated below 5 mg of copper per kilogram of dry matter, and some sit near 3 mg/kg DM. For a 20 kg dog, that's roughly 1.3 mg of copper per day versus 5 mg or more on a typical maintenance formula. Your veterinarian sets the individual target based on biopsy results, breed, and whether chelation therapy is in play.

Restriction is only half of it. Dietary zinc can compete with copper for intestinal absorption, and some vets use zinc supplementation alongside diet — but dosing is genuinely narrow and belongs entirely to your veterinary team, not a shelf product. The same applies to prescription chelators. Never start either on your own.

Which dog breeds are prone to copper storage hepatopathy?

Bedlington Terriers carry the best-characterized genetic form, linked to a COMMD1 gene deletion, with reported carrier rates historically above 50% in some lines. Labrador Retrievers, Doberman Pinschers, Dalmatians, West Highland White Terriers, and Skye Terriers are also over-represented in the veterinary literature.

Breed risk doesn't equal disease. Plenty of Labs live long lives on standard food. What breed risk does justify is earlier bloodwork — many vets check ALT and ALP annually from middle age in at-risk breeds — and a preference for formulas that don't stack liver, duck, and legumes on top of a supplemental copper source. The American Kennel Club breed health pages are a reasonable starting point for understanding inherited risk in your dog's line.

Can I feed raw or homemade food to a dog with high liver copper?

Raw and homemade diets can be built low in copper, but only with formulation help, because organ meat is the single richest copper source in a typical raw recipe — beef liver alone runs close to 9–10 mg of copper per 100 g. A 20 kg dog's entire daily allowance can be exceeded by 15 g of liver.

If you're committed to fresh feeding, work with a board-certified veterinary nutritionist who can build a recipe using lower-copper proteins — chicken, turkey, eggs, cottage cheese, and white fish — with rice or oats as the carbohydrate base and a copper-free mineral premix. Off-the-shelf raw dog food is formulated for healthy dogs and usually includes organ meat by design, so it isn't a default fit for this diagnosis.

Do treats and chews matter on a low-copper diet?

Yes — treats should stay under 10% of daily calories on any therapeutic diet, and on a copper-restricted plan the composition matters as much as the calories. Freeze-dried liver, duck, lamb, and shellfish-based chews are all concentrated copper sources. Swapping to single-ingredient chicken or turkey options solves most of the problem.

When customers ask, we point them toward plain poultry or whitefish options in our dog treats selection and away from anything organ-based. Dental chews and rawhide alternatives are generally low in copper, but check for added liver flavouring.

How to choose a lower-copper food you can actually buy

No over-the-counter Canadian dog food is marketed as "low copper," so selection comes down to three filters: a protein that isn't liver, duck, or lamb; a limited ingredient list without heavy legume loading; and a manufacturer willing to share typical copper values in mg/kg dry matter. Everything else is guesswork.

Ingredients worth flagging on the label — all naturally moderate-to-high in copper — include liver and other organ meats, duck, lamb, pork, shellfish such as mussels and oysters, lentils and chickpeas, sunflower seeds, and mushrooms. Lower-copper building blocks include chicken, turkey, eggs, white fish, dairy proteins, rice, and oats. Protein content itself doesn't need to be slashed for most copper-associated hepatopathy cases; adequate protein supports liver regeneration, and restriction is typically reserved for dogs showing hepatic encephalopathy. That's a call for your vet.

Two limited-ingredient starting points our customers frequently bring to their veterinarians for review:

Neither is a substitute for a veterinary therapeutic hepatic diet if your vet has prescribed one — those require veterinary authorization and are formulated specifically for copper restriction. Where a retail store helps is everything around the prescription: palatable low-copper toppers, appropriate treats, and the milk thistle or SAMe products your vet may add. Browse our dog health and wellness range or read more about dog wellness needs before adding anything, and clear every supplement with your vet first — liver patients metabolize compounds differently than healthy dogs.

Feeding volume is the other half of the equation. If your dog is on a restricted formula, weigh meals rather than scooping; a 10% overfeed on a 30 kg dog adds roughly 0.18 mg of copper daily, which compounds over years. Our guide to pet food for specific health needs covers portioning by weight in more detail, and the Canadian Veterinary Medical Association can help you locate a specialist referral in Ontario.

Our store at 1111A Finch Ave W, Unit 2, North York, ON M3J 2P7 is open 7 AM to 11 PM daily, with local delivery available via DoorDash and other apps. Bring your dog's discharge notes and we'll help you shortlist options to run past your vet — or contact our team ahead of time.

Key takeaway: Therapeutic low-copper diets for dogs sit below 5 mg/kg dry matter — about 0.5 mg daily for a 5 kg dog and 2.3 mg for a 40 kg dog — while AAFCO's adult minimum of 7.3 mg/kg DM lets typical foods run three to five times higher. Screen labels for liver, duck, lamb, and shellfish, request typical copper analyses from manufacturers, and let your veterinarian confirm the target based on biopsy results.