Liver is Nature's Multivitamin

Of all the parts of a deer, liver is the one people have prized the longest. Cooks have turned it into pâté and terrine for centuries. Japan has its own long tradition of レバー [rebā, liver] cooking. Long before anyone measured a vitamin, liver carried a reputation as a kind of natural tonic.

The modern figures support that reputation. Liver is one of the most nutrient-dense foods there is. Gram for gram, very little else in the natural world is as concentrated.

The liver in our recipe comes from the same wild sika deer (ニホンジカ [nihonjika, Japanese sika deer]) as the muscle meat and heart.

Why a measured amount

Liver is naturally rich in vitamin A, copper, iron, folate, vitamin B12 and choline. That is exactly why it belongs in a meal topper recipe in a small, carefully measured amount: a few percent, no more.

Vitamin A is fat-soluble and copper is a trace mineral. Both are stored in the body rather than flushed out, and there are well-established upper limits for vitamin A in dog food. Liver is potent enough that a little goes a long way. Getting the proportion right is part of the craft of the food.

It is also how people eat liver: a smear of pâté, not a plateful, for much the same reason.

The care is the quality

Liver is one of the most perishable parts of animal meat. That makes handling especially important.

Our deer are processed the same day they are taken, at a licensed facility in Nagano, under the same hygiene standard that makes fresh, human-grade wild meat possible. Nagano's game industry works to the prefecture's Shinshu gibier hygiene guidelines (信州ジビエ衛生管理ガイドライン), and our venison comes from a processor operating to that standard.

Plated, it is unmistakable: deep burgundy, dense and almost silky when fresh, with a mineral, umami depth. We use only a little of it in VENISON + APPLE, but that little carries a great deal. It means the whole animal, right down to its darkest and most concentrated part, goes to good use.

Karuizawa Harvest makes whole-food meal toppers for dogs. We're based in Karuizawa, Nagano. For more on what goes into VENISON  + APPLE, and news of our autumn 2026 release, leave your email below.

Notes & sources

• Liver nutrient density (vitamin A, copper, iron, folate, B12, choline): USDA FoodData Central · 日本食品標準成分表2020年版(八訂): MEXT Food Composition Database

• Vitamin A as a fat-soluble, stored vitamin: NIH Office of Dietary Supplements, Vitamin A