Every Health Claim Made About Cow Ears, Checked Against a Source

The studies reviewed here do not establish a joint-health result for a cow-ear chew, and Foodiepaws does not sell cow ears, so nothing here is written to move a product. You are probably here because your dog is slower off the rug than last year, and a bag said cartilage. It's the loudest claim in the aisle and the thinnest.

A cow ear is a cattle ear dried whole — skin over cartilage. Six claims ride on that cartilage: joints, teeth, skin, coat, boredom and anxiety. Each one gets the same question below: is there a study, or isn't there?

How each claim was checked

The method is dull on purpose, and you can run it yourself. Take the claim as the seller words it. Search the US National Library of Medicine's index for the chew and the species. Read what comes back — then report it, whichever way it falls.

A targeted PubMed search is one way to look for relevant publications. Search terms and indexing limit what it finds; a search result is not a complete inventory of manufacturer testing.

The six claims, side by side

Claim made for cow ears	What the check found
Supports joint health	The reviewed sources do not establish a product-specific joint benefit or composition.
Cleans teeth	No cow ear appears on the veterinary dental accepted-products list.
Better skin and coat	The reviewed sources do not establish a cow-ear skin or coat benefit.
Fixes boredom	Chewing has a literature. The cow ear does not.
Calms an anxious dog	The cited stress studies concern humans or rodents, not a cow-ear trial in dogs.
70 to 80 percent protein	Use the particular maker's product declaration; the reviewed sources provide no universal value.

An empty evidence column does not make a claim false, and it does not prove no work was done. It means this review did not locate the product-specific evidence needed to assess that claim. A maker may hold additional records; ask about the particular product and outcome.

Cow ears for joint health: what the real trials dosed

The joint claim runs cartilage to collagen to hips and stops there. Nobody shows you the middle. Oral collagen has been trialled in dogs more than once, and what those trials dosed is the part the bag never mentions.

A 2024 trial in PLOS ONE finished with thirty-one dogs, and the dose was nothing like a chew. Each dog got roughly 240 mg of a bioactive collagen peptide per kilogram of body weight, daily, for twelve weeks. It came as a white powder, mixed with water and stirred into the feed.

Do the arithmetic. A 50 lb dog is about 23 kg, so that's near 5.4 grams of measured powder a day, three months running. A 2022 study in Scientific Reports dosed a tablet instead: 40 mg a day for thirty days. Powder or tablet, somebody weighed it.

A cow ear is none of those things. It is not the measured hydrolysed preparation used in those trials, so their results cannot be transferred to an ordinary cow ear. Those trials are real, and they are why we are precise about our own collagen chews rather than vague — what a collagen chew supplies sets out the difference between feeding the protein and dosing a peptide. If your dog already has a mobility diagnosis, that plan belongs to your vet, not to a treat aisle.

Dental: what chewing does, and where the claim stops

VCA Animal Hospitals reports that over 80% of dogs older than three have active dental disease. So you have a reason to want a chew to help, and a dog who would happily volunteer for the trial.

Read the hedge in VCA's own wording, though. Chew toys and treats "may also help reduce or delay plaque and tartar build-up." Three hedges in six words — and the same page names daily brushing as the thing that prevents build-up.

Then check the list. VCA points you to the Veterinary Oral Health Council, whose seal goes only to products shown to cut plaque or tartar. Search the accepted-products list for a cow ear and you won't find one. No bully stick is on it either, ours included — an absence that establishes neither failed testing nor the absence of all testing.

Skin, coat, boredom and anxiety

Skin and coat is the joint claim wearing a different hat. Same cartilage, same missing study. A dull coat usually has causes no chew can reach, so if your dog is scratching and it won't settle, that's a workup with your vet, not a treat swap.

Boredom and anxiety are where a real thread appears. A 2025 University of Sydney review of chewing in dogs calls the behaviour good for a dog's physical and psychological health — then says its relevance to a dog's comfort, health and purpose remains unclear.

Read where the calming evidence comes from. The stress research in that review is human, mouse and rat. Its one canine note: fearful dogs did better on a spatial memory test right after five minutes of chewing. The review says outright that it leans on other species to fill gaps in the dog literature.

Notice what that's evidence about. Chewing — not cow ears. Dogs pick their chews by odour, taste and mouthfeel, and a bored dog will settle with a cow ear, a bully stick, or a cardboard box. Credit the behaviour, not the ingredient.

Use the product's own nutrition information

"70 to 80 percent protein by weight" rides on cow ear listings with nothing under it. The circulating calorie figures are no better, and they contradict each other. None of them traces back to a published analysis, so none of them is printed here.

Here's what a sourced number reads like instead. Two board-certified veterinary nutritionists, Laura Gaylord and Donna Raditic, put bully sticks at roughly 15 kcal per inch in Today's Veterinary Practice. Named authors, a journal, and a unit you can act on.

Those nutritionists recommend useful product information. Look for calorie content, a full ingredient list and a guaranteed analysis. Those declarations describe the maker's product; they are not replaced by a result for another chew. Ask the maker for the information your vet needs, and use it when considering portion size and digestive tolerance.

The same test, run on our own shelf

The dental review those two cite deserves one more sentence. Nine studies on non-rawhide dental chews, and firm conclusions were hard to reach because the study designs were weak. Those were products built for the job.

So we hold our own shelf to it. We do say our lamb collagen sticks support joints, and that claim rests on what the chew is rather than on a trial of a stick: cartilage, tendons and ligaments are collagen, and ours is that same protein, single ingredient and dried whole. What a collagen chew supplies sets it out in full, including what the canine trials actually dosed. A cow ear should be assessed using its own ingredient and nutrition information, without transferring trial outcomes from a different product. We also publish our calorie content and guaranteed analysis, which is the bar those two nutritionists set.

If risk is what actually brought you here, the cow ear safety answer covers size, fat and supervision. If you're weighing one chew against another, cow ears against bully sticks does that comparison.

Cow ear health claim FAQ

Do cow ears have glucosamine or chondroitin?

The publications reviewed here do not provide a glucosamine or chondroitin value for a particular cow-ear product. That does not prove a maker's figure has no basis. Ask what product, sample and method its number describes; a composition figure alone is not proof of a clinical joint benefit.

Are cow ears good for a dog's skin and coat?

The studies discussed here do not establish a skin or coat benefit from cow-ear chews. That is the limit of this review, not proof that no other records exist. If your dog's coat or skin changes, ask your vet about the cause rather than relying on a chew claim.

Do cow ears clean a dog's teeth?

Chewing anything is mechanically abrasive, and VCA puts that at "may also help reduce or delay plaque and tartar build-up" for chew treats generally. No cow ear appears on the Veterinary Oral Health Council's accepted list, but that list alone does not establish whether a particular maker holds other evidence. Brushing is the part that has. Use a chew for what it is, and brush anyway.

A cow ear is a dried piece of cow, and most dogs are delighted by it. That is the whole of what anyone can prove. Judge it on size, fat and supervision. We don't sell them, so the sixty-second chew quiz asks about your dog instead.