What Are Bully Sticks Made Of? Everything You Need to Know [2026]

A study published in the Canadian Veterinary Journal found that only 44% of the general public could correctly identify what bully sticks are made of. Even 38% of veterinarians got it wrong. Below: the ingredient, where it comes from, why dogs lose their minds over it, how it's processed, and 6 red flags to avoid when buying.

📖 Part of the Ultimate Bully Sticks Guide. See also: Are Bully Sticks Safe? · Best Bully Sticks 2026 · Which Are Safest?

What Are Bully Sticks Made Of?

Beef pizzle. That's the polite term for the penis muscle of a bull. One ingredient, one animal part. No grains, no binding agents, no mystery meat blends.

The tissue is dense muscle, which is why the protein content is unusually high (80-97% crude protein depending on processing method) and the fat content is low. Beef pizzle is tough, fibrous, and naturally chewy. That combination is what makes bully sticks last longer than most treats while still being fully digestible. Unlike cooked bones, they won't splinter. Unlike rawhide, they break down safely in the stomach.

The word "pizzle" comes from the Low German "pesel" or Dutch "pees," meaning sinew or tendon. It's been used in English since the 15th century. You'll see "beef pizzle" on ingredient labels for this reason. Other names for bully sticks: pizzle sticks, beef sticks, bull pizzles. All the same product.

And the name "bully stick" itself? Bull (the source animal) + stick (the shape). Simple.

Where Do Bully Sticks Come From?

Bully sticks come from cattle raised for beef production. The pizzle is a byproduct of the meat industry: if it weren't made into dog chews, it would be discarded. Using it turns waste into one of the most nutritious natural treats available, which makes bully sticks a more sustainable option than treats that require dedicated animal farming.

But not all sourcing is equal. Where and how the cattle were raised directly affects the quality of the final product. Cattle raised on open pasture produce denser muscle tissue with higher Omega-3 levels, more conjugated linoleic acid (CLA), and more vitamins A, D, E, and K compared to grain-fed feedlot cattle. That density also translates to a tougher chew that lasts longer.

The questions to ask about any bully stick brand: Were the cattle grass-fed or grain-fed? Were they given growth hormones or routine antibiotics? Was the slaughter process humane and regulated? Does the manufacturer control the entire supply chain, or are they buying from whoever is cheapest?

How Bully Sticks Are Made

The manufacturing process is what separates a safe, nutritious bully stick from one that's cheap, chemically treated, and potentially contaminated. Two sticks can look identical on the shelf and be completely different products underneath.

Here's how Natural Farm makes bully sticks, entirely in-house:

Bully Stick Nutritional Profile

Single-ingredient means the nutritional profile is straightforward. No fillers diluting the numbers:

Numbers vary by stick size, thickness, and processing method. Rawhide is low in fat but poses digestibility and chemical processing risks.

The fat difference is significant. Pig ears contain roughly 10x more fat than a standard bully stick. For dogs on calorie-restricted or low-fat diets, that distinction matters.

Natural Farm's Cold-Dried™ Bully Sticks push the profile further: up to 97% crude protein and just 1% fat. The proprietary low-temperature drying preserves more of the natural protein structure, producing a denser beef dog chew. For a full comparison of all types, see our 10 best bully sticks for dogs ranked by size.

Are Bully Sticks Safe?

Yes. Bully sticks are one of the safest long-lasting digestible dog chews available. They won't splinter, and they contain a single natural ingredient with no chemicals or preservatives. The one rule: always supervise and remove the last 2-3 inches to prevent choking. That small end piece is the only real risk.

The safety of a bully stick depends almost entirely on how it was sourced and processed. A stick from grass-fed cattle, manufactured in a USDA-inspected facility, and third-party tested for pathogens is a different product from one imported from an unregulated facility with no testing. The ingredient is the same. The safety profile is not.

📖 Full safety guide · Can puppies have bully sticks? · When to take one away

Bully Sticks vs Rawhide

They look similar on the shelf. They are fundamentally different products:

Natural Farm Power Chews won the Pet Innovation Awards 2023 Rawhide Alternative of the Year. For a complete safety comparison, read which bully sticks are the safest.

What to Look For When Buying

Natural Farm meets all six criteria and publishes its FDA facility registration publicly. Rated "Best Overall" bully stick by The Spruce Pets for five consecutive years.

Why Dogs Love Bully Sticks

Dogs and wolves eat organ meat first after a kill because it's the most nutrient-dense part of the animal. Beef pizzle triggers that same instinctual attraction: the natural aroma signals high-value protein, and the flavor intensifies as the stick softens.

The texture sits in the sweet spot between hard enough to satisfy the chewing urge and soft enough to gradually break down. And sustained chewing releases endorphins, leaving dogs calmer, less anxious, and less destructive. A bully stick session isn't just a treat. It's mental health maintenance.