The Hidden Dimension in Pet Food: 3D and 4D Meats


The Hidden Dimension in Pet Food: 3D and 4D Meats

Dear Ask Darwin’s,

I heard that some pet food companies use 3D and 4D meats.  I am hoping you don’t’.

Heather, New York

Dear Heather,

We absolutely, positively do not!

3D and 4D Meats in Pet Food

There’s an old saying “You are what you eat.” If that’s true, then it’s important that animal lovers take extra care when we decide what to feed our pets. This article is a deep dive into what’s true, what’s legal, and what you must understand about meat and food labeling in pet food. Be prepared: what you may unknowingly be feeding your animal companion may shock you.

It’s hard to find information – in fact, the USDA recently removed animal welfare and even food-related information from its site. What’s a concerned pet owner to do? We asked expert Steve Brown to weigh in on what you need to know to be a better consumer and demand greater transparency from pet food brands.

Steve Brown is a dog food formulator, researcher, and author on canine nutrition. In the 1990s he developed one of the leading low-calorie training treats, Charlee Bear® Dog Treats, as well as the first AAFCO-compliant raw dog food. Since 2003 he has focused on research and education. He is the author of two books on canine nutrition (See Spot Live Longernow in its 8th printing, and Unlocking the Canine Ancestral Diet (Dogwise Publishing, 2010); and a 40-page booklet, See Spot Live Longer the ABC Way. 

You may not have heard the terms before, although it’s likely you’ve fed it to your pets at some point: 3D and 4D meats.

3D and 4D Defined

The term comes from the first letter of the description of meat from animals which are dead, diseased, dying (or downed)—that’s 3D—but the animals are still alive. The 4th “D” is destroyed (all 4 or 4D), which means that the animal is dead. Both 3D and 4D animal bodies are salvaged for rendering, and are considered unfit for human consumption—but acceptable as animal feed.

Meat Processing and the Rendering of 3D and 4D Animal Tissue

Rendering converts waste animal tissue into end products that can be used in various products. According to An Overview of the Rendering Industry, “annual volume in the United States is approximately 11.2 billion pounds of animal-derived proteins and 10.9 billion pounds of rendered fats.” Some of the products are used for soaps, paints and varnishes, cosmetics, explosives, toothpaste, pharmaceuticals, leather, textiles, and lubricants, but much of it—about 85 percent—of this production is utilized as animal feed ingredients.

Animal sources most commonly used are chickens, cows, sheep, and pigs. Processed tissue usually derives from slaughterhouses, and includes 3D and 4D meats. Other sources include animals that have died in transit, including roadkill, and on farms.  Sources also include butcher shop trimmings, expired meat from grocery stores and restaurant grease. Material includes the bones, fatty tissue, bones, and offal (entrails and internal organs).

Learn more about the process and products in the information provided by the National Renderers Association.

Euthanized Pets and Rendering

Animals who have died or been euthanized in animal shelters can be rendered. Here’s a quote from the Environmental Protection Agency (EPA): “Meat rendering plants process animal by-product materials for the production of tallow, grease, and high-protein meat and bone meal.  Plants that operate in conjunction with animal slaughterhouses or poultry processing plants are called integrated rendering plants.  Plants that collect their raw materials from a variety of offsite sources are called independent rendering plants.  Independent plants obtain animal by-product materials, including grease, blood, feathers, offal, and entire animal carcasses, from the following sources:  butcher shops, supermarkets, restaurants, fast-food chains, poultry processors, slaughterhouses, farms, ranches, feedlots, and animal shelters.”  

If the thought of feeding your dog or cat one of its own species is disturbing, read on to find out more about what you can do to understand the content of your pet’s food.

The Dangers of 3D and 4D Meats

“In the short term, immediately after consumption, some dogs may get sick due to poor quality meats,” says Brown. “I think it’s rare, though. I am much more concerned with the long-term effects of eating poor quality meats: 3D, 4D, old meats, and poorly handled meats. All meats contain fats, and the studies are conclusive, long-term consumption of rancid and poor quality fats leads to chronic diseases and loss of cognitive functions. In other words, feed good quality meats.”

Exposure to Denaturing Agents

Denaturing is a way of identifying or staining meat products in the rendering process to identify it as feed-grade, or finished product unfit for human consumption which only be legally fed to animals. Charcoal, fish meal, or a chemical agent or agents are used to mark the meat and apply a distinct odor, color or taste so it doesn’t enter the human food chain – a signifier that it is of low quality in other words.

Exposure to Medications

In Slate the article “A Dog-Eat-Dog World” goes into greater depth about animals that were formerly pets being part of rendered meats. It also covers notes that the drugs these animals may have been medicated with—antibiotics, steroids, and the sodium pentobarbital used to euthanize animals in shelters—aren’t neutralized by the rendering process.

If there are so many dangers in 3D and 4D meats, why isn’t something being done about it by government regulation?

Government Regulations and Pet Food Standards

There are rules in place that govern the pet food industry—it’s just that they don’t prohibit the use of rendered 3D and 4D meats in ‘feed grade meats.’ Pet foods aren’t regulated as food per se; they are regulated as animal feed.

The United States Department of Agriculture (USDA) and Pet Food

Animal processing for slaughter and meat are regulated by the USDA. Animals and meat are under its authority until the products are designated as pet food or feed grade meats. At that point, the products are regulated as animal feed, and processing is regulated by the FDA and state feed-control programs.

The United States Food and Drug Administration (FDA) and Pet Food

The FDA oversees most of the U.S. food supply, and its authority applies primarily to products in interstate commerce and imported products. Because of the way ingredients are received and finished products are distributed, most pet food products are associated with interstate commerce.

Here’s what the FDA says about rendering and animal/pet feed: “Rendered animal feed ingredients include the various poultry, meat, and marine products which result from the rendering of these animal tissues. Rendering of poultry and other animal tissues has been practiced for over a hundred years as a means of salvaging valuable protein and fat content from otherwise waste material. For many years’ end products from rendering have been used to feed animals. The rendering industry utilizes packinghouse offal, meat processing waste, restaurant waste and animal tissues from other sources including animals that have died otherwise than by slaughter.”

Meaning, that 3D and 4D meats are acceptable and that the products of rendering are legal to include in pet food, as long as they are noted on the product ingredient list.

The Use of 3D and 4D Meats in the Dog Racing Industry

Dogs used in racing – usually greyhounds – are fed a 4D based diet, for economic reasons, although even the USDA states that 4D meat served raw is a health hazard to humans who handle it and animals that consume it. Raw 4D meat exposes people and racing dogs to pathogens including E-coli, Salmonella, and Campylobacter jejuni.

“Racing dogs are fed for short-term results, and they are fed a lot of fat because they need a lot of calories,” says Brown. “Most of the problems with 3D and 4D meats and poor quality fats are long-term chronic health problems.”

You can learn more about greyhounds in racing, their treatment, and find ways to take action from Grey2KUSA Worldwide.

Becoming a Better Pet Food Consumer

As we mentioned earlier, pet food is regulated as animal feed and therefore doesn’t follow food safety law. The FDA openly tells the pet food industry that “Pet food consisting of material from diseased animals or animals which have died otherwise than by slaughter… will be considered fit for animal consumption.”

Human Grade Pet Food

Are there ‘real’ foods out there for pets? Yes, but they are few and far between. Pet foods manufactured in a certified human food facility, include 100% human food quality ingredients which are USDA inspected and approved as human edible qualify. ‘Human grade’ will be stated on the pet food label if the product meets the legal requirements.

Meat Chunks

The pieces of meat in some canned pet food may look real, but many times they aren’t. Fabricated meat is made from meat slurry with added vegetable starches to hold the right form and fool the eye. If there are many starches listed on the product label, you may be looking at ‘faux meat.’

“Inspected” Doesn’t Necessarily Mean “Approved”

“Inspected” means that meat has been reviewed and labeled according to USDA standards, but don’t necessarily mean that it is of high quality. Inspectors check the condition of the animals, including their ability to walk on and off of transport vehicles. If they’re not, they are usually identified as 3D or 4D. USDA “Approved” means that the food is suitable for human consumption.

Processing Matters

“The best meats for dogs are those that are naturally raised, in the pasture, and processed humanely. Processing matters” says, Brown. “Whether the animal is fed organic food or not isn’t as important as how the animal was raised and processed. He goes on to say, “I’ve seen lots of test reports and looking at the test reports on fats, vitamins, and minerals in the meats, I find that grass-fed, naturally-raised and humanely process is more important than whether or not the animal was fed organic foods. A cow fed organic corn is still a corn-fed cow, and the fats will differ from a naturally raised cow.”

The Use of 3D and 4D Meats in Non-Raw and Raw Pet Foods

According to the Association for Truth in Pet Food, both non-raw and raw pet foods may use 3D and 4D meats and often are, since it’s not illegal. It’s hard to get at the truth since pet food definitions are not public: the AAFCO organization holds control over these definitions, and charge $100 for access. Either you must pay the fee, trust the manufacturer, or do your own due diligence and do some digging on your own.”

Taking Charge with the Right Questions

Since the FDA doesn’t safeguard pet foods as it does human quality food, the key questions to ask is if the pet food is about sourcing and to get a clear answer about whether or not the company allows the use of 3D or 4D meats in its products. Many companies now provide transparency or definite answers about what kind of meat goes into their foods – but if you’re concerned about the use of and can’t get a direct answer about sourcing, you should keep looking until you find a food that provides the quality ingredients you’re looking for.

“Where Exactly Does the Food Come From? Is it Human Grade?”

Since pet food labeling can be something of a mystery, you must ask for a detailed explanation of sourcing and in reality, whether it is human edible meat to ensure that it’s of the best quality. “Most raw food manufacturers don’t disclose the source of the meat, how fresh it is, whether it’s human grade or not,” says Brown. “As one of the founders of this industry, this is hard to say but true: many companies lie, they’ll say it’s human grade when it’s not. Human grade meats are considerably more expensive than 3D or 4D meats and some companies prioritize profits over honesty and the health of your pet and say human-grade when it’s not. You can often tell by the price.”

“Is Tripe Good for My Pet?”

Green (not white) tripe is derived from the stomach of grazing animals could come from healthy cows, sheep or buffalo or from a 3D or 4D animal. Often, it will be denatured because green tripe isn’t listed as a food item for human consumption. Pets love green tripe and it’s a nutrient-rich food source for them, but you need to make sure that the tripe you serve comes from all-natural sourcing. “Most dogs love tripe, probably more than anything except, with my dogs, ice cream,” says Brown. “I sometimes feed tripe just as a special treat for them. Tripe is nutritious and part of their natural diet.”

“Is it Marketing – or Is It Meat?”

Misleading images on pet food labels are a direct violation of federal law and many state laws, but currently, no authority enforces those laws. Images of food on pet food labels are in most cases only marketing.

“Is it Better to Feed Table Scraps or Kibble from Good Sources Instead of Raw Potentially 3D or 4D Meat?”

“For most dogs,” says Brown, “I think feeding a recently-produced, basic, high-quality kibble and adding up to 15% fresh, whole foods such as leftover vegetables and meats is healthier than a raw diet that uses3D/4D or poorly handled meats.” He also says, “Even better, for those on a tight budget, feed kibble 5 days a week and a high quality like Darwin’s 1-2 days a week.”

Find out more about how to be a better consumer and compare different types of pet food.

Terms to Understand to be a Better Pet Food Consumer

We’ve already covered some of the terms in the article, but here’s a checklist to use the next time you buy pet food when you want to understand ingredients and if 3D and 4D meats are included.

Common Pet Food Labeling Terms Checklist Animal Fat: Not human grade. This greasy waste left over after rendering generated from the tissues of mammals and/or poultry. Bone Meal: Not human grade. Made from un-decomposed bones, it’s steamed, dried & ground. Meat fiber, grease, and gelatin can sometimes be included. Meat and Bone Meal: Not human grade. This is a dry rendered product from mammal tissues made from slaughterhouse waste and other dead animals. It includes bone and may include hair, hoof, manure, blood and stomach contents in small amounts. Meat by Name: If a pet food has a type of meat in the title, like Beef or Tuna, the product must have a minimum of 70% of that type of meat content. Meat Meal (including better, lamb, and venison): Not human grade. A rendered product from mammal tissues unfit for human consumption. It includes bone and may include hair, hoof, manure, blood and stomach contents in small amounts. Organic There are several different types of organic labels. Here are the USDA standards for organic labeling: “100% organic,” which means the product is entirely organic “organic”, which applies to a product with 95% organic ingredients, and “Made with Organic_____.” is a product with at least 70% organically produced ingredients. Poultry by-product meal: Not fit for human consumption. A dry product of rendering made from slaughtered poultry which includes no muscle meat. It may include viscera, beaks, heads, intestines, neck and undeveloped eggs. “With” If a pet food name includes the word with – for example, [Brand Name] with Chicken – regulations only require that a 3% minimum of the named meat is included.

We Want You to Know:

Darwin’s Never Includes 3D or 4D Meats

At Darwin’s we’re all about transparency!  Our Natural Selections meals contain only free-range, grass-fed beef, cage-free poultry and organic vegetables. All our meats are hormone free, steroid free and antibiotic free.

We visit every farm that raises the animals we use in our meals to make sure they employ good farming practices and treat both their animals and employees with respect.

Our meats are grain free, free range, cage free, grass fed. Free of steroids with no artificial growth hormones, ever.

Talk to a Darwin’s Pet Food Advisor Learn more about the high-quality standards of our pet foods. We want you to know what’s in our food!

Call 877-738-6325 or drop us an email.

What to see inside Darwin’s Pet Food factory?

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