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Myths and Truths about Air-Dried Bones versus Raw Bones

This content is owned by Feed Real Institute. Authored and/or contributed to by Kay S..

Myths and Truths about Air-Dried Bones versus Raw Bones

The topic of dogs and bones is a never-ending controversial debate. Most veterinarians say it is unsafe to feed a dog bones, yet the stereotypical photos of dogs often include a bone. “Give a dog a bone” is more than a verse from a nursery rhyme - dogs need calcium from bones in their diet. 

Conversations about dogs and bones rarely reveal what happens to bones when processed. This article will explain the benefits and potential risks of giving bones.

What We Have Learned

Throughout our journey of learning about the benefits of a species-appropriate diet that includes raw meaty bones, we have reached these conclusions:

  • Dogs need calcium in their diet. Bones are an excellent, natural source of calcium for your dog.
  • All bones splinter: The processing method of bones can vary: raw, air-dried, cooked, dehydrated, or freeze-dried, but the bottom line is that all bones splinter into sharp pieces when broken.
  • Not all bones are equal. Raw meaty bones and air-dried bones are covered with meat and connective tissue that aids in the digestion of the bone. Prolonged cooking at temperatures that exceed 160 °F changes the bone’s cellular structure and breaks down the protective muscle and connective material around the bone. Key components necessary for proper digestion, including moisture, are leached from the bones during this high-heat process, making the bone materials less digestible for dogs.
  • The pH of the dog’s stomach is comparable to battery acid, making it possible for dogs to digest RMBs and freeze-dried and air-dried bones.
  • Your dog’s poop reflects what he has eaten. If too much bone is consumed, his stools may be white and chalky. It is also normal to see small, undigested bone pieces in poop. Loose stools can indicate that too little bone is being fed.
  • Bones are often thought to be a choking hazard. The structure of the esophagus is thicker and wider in the dog. Giving your dog the right size bone is vital based on the mouth and chewing behaviors.
  • Giving your dog edible and recreational bone benefits includes great exercise for the jaw, natural teeth, gum cleaning, and mental stimulation.

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Before discussing the history of animals eating bones, let’s look at a common scenario. It is the middle of the dry season on the Serengeti, with the daily temperatures hovering around 80℉. A small pride of lions has finished feasting on the 450-pound kudu bull. 

What remains is left to the scavengers. The hyena will feed on the carcass for days despite the bones being exposed to the hot desert conditions for prolonged periods. It can still consume and digest the bones with its powerful jaws. 

The hyenas’ meals consist of such high levels of bone that their feces are easily distinguished from the stool of other species due to their chalky white appearance- a common phenomenon seen in raw-fed dogs’ stools if the dog has too much bone in its diet. Although hyenas are not canids but are more like cats, they share similar opportunistic scavenging behavior and nutritional requirements to our domesticated dogs. 

The History of Canids Eating Bones

Wild canids, Family Canidae, are predatory carnivores that consume whole prey, including bones. Before domestication, the wolf connected with humans due to the mutual benefit of hunting. Wolves scavenged from the hunters' kills, consuming the ribs and other smaller bones that were not edible to humans. Eating bones is a natural behavior for canids.

Food caching is a behavioral strategy in which wolves and other canids, such as coyotes and foxes, store portions of their kills for later consumption. Canids are single-item-surplus cachers as they only cache food when they cannot consume all of it in one sitting. Although some nutritional value is lost due to the food being exposed to the elements (such as wind, heat, and humidity), the benefits of having food during scarcity outweigh the losses.

The degree of food degradation depends on the food type, the duration of exposure to the elements, and the storage location. Because canids are known to eat their prey's organs, intestinal contents, and some fleshy muscle meat first, the cached food is usually the skeletal remains, the hide, and some muscle meat. The wolves will later consume the remaining flesh bones, and hide after days or even months of environmental exposure.

Scavengers, such as hyenas and coyotes, consume any body parts left from a kill made by other animals. Hyenas are voracious bone eaters. The hyenas’ feces have a chalky white quality that distinguishes them from the stools of different species. As scavengers, they rarely eat freshly killed carcasses, so the bones they consume may be air-dried from exposure to the elements. 

After the reintroduction of wolves into Yellowstone National Park, coyotes were no longer the apex predatory carnivores. Scavenging from wolf kills has become necessary for their survival. Kills are visited by coyotes for several days, up to two weeks.

Modern dogs not only share 98.8% of the same DNA as wolves, but they also share their behavioral characteristics. Free-ranging domestic dogs are considered the most successful scavengers in Zimbabwe. When allowed to raid garbage cans, our pet dogs scavenge, looking for tasty scraps, caching their most prized toy, or chew for later enjoyment.

What Is Bone Composed Of?

Bones consist of two components: a mineral or inorganic phase that provides strength and stiffness to the bone and an organic matrix primarily made up of Type 1 collagen that influences the toughness of the bone. The mineral content constitutes 60%, the organic content is 30%, and the remaining 10% is water. 

Collagen is the organic component of bone that consists of a fibrous protein. The inorganic mineral component interspersed among the collagen fibers consists of carbonated hydroxyapatite, calcium phosphates, carbonates, and other minerals such as sodium, magnesium, potassium, sulfur, barium, fluorine, and choline. Although the water content is only 10%, it is crucial to the mechanical behavior of bone. 

Avian (or bird) bones are of two varieties: pneumatic and medullary. The pneumatic bones are hollow bones connected to the respiratory system, including the skull, humerus, clavicle, keel, pelvic girdle, and lumbar and sacral vertebrae. The medullary bones include the tibia, femur, pubic bones, ribs, ulna, toes, and scapula. The composition is comparable to that of mammalian bones, except for the low density of the pneumatic bones. 

Why Dogs Need Bone in Their Diet

Why dogs need bones in their diet is a topic in and of itself, but the short answer is that bones provide your dog with essential nutrients, natural dental care, exercise for the jaws, and mental stimulation. 

There are two types of bones: edible nutritional and recreational bones. Nutritional raw bones provide calcium and other minerals to your dog’s diet. They can be fed whole or ground into a bone meal. 

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Nutritional bones are the softer and often hollow bones in birds, including:

  • Chicken/Duck Breasts
  • Chicken/Duck Heads
  • Chicken/Duck Legs
  • Chicken/Duck Quarters
  • Chicken/Duck/Turkey Wings
  • Chicken/Duck Carcass
  • Chicken/Duck/Turkey Feet
  • Chicken/Duck/Turkey Necks
  • Whole quail

Mammalian bones that are good nutritional bones include:

  • Lamb Neck
  • Lamb/Pork Ribs
  • Whole Rabbit
  • Rabbit Head
  • Pork Feet
  • Pork Tails

For large dogs 

  • Pork Ribs
  • Beef Short Ribs (not long)
  • Oxtail

A recreational bone provides jaw exercises, mental stimulation, and oral care. These are knucklebones, rib bones, and small femur bones. Dogs will spend extra time gnawing outside, licking, and chewing at the center to extract the marrow. Discard these bones after the chewing session.

Do not use the large femur bones of cows or pigs, as they are too strong. They are reinforced with zinc and iron to provide strength, so your dog will exert excessive force with his teeth and jaw to chew on these bones.  

Both nutritional and recreational bones aid with natural dental care. Dogs with poor oral health are at a greater risk for heart and kidney diseases. Many of these dogs are also immunocompromised. According to the American Veterinary Medical Association (AVMA), up to 80% of dogs will have oral disease by two years! Studies of wild wolves indicated that only 9% of the skulls examined had any evidence of periodontal disease. Why the difference? Biting, tearing, and crunching whole carcasses and bones promote good oral health.

Bones to use recreationally (not completely edible):

  • Marrow bones
  • Knucklebones
  • Rib bones
  • Small femur bones

Bones or chews to avoid:

  • Weight-bearing bones from large animals such as cows as these bones are too hard for aggressive chewers and can cause tooth fractures.
  • Machine-cut bones such as pork chops or steaks have sharp edges that can cause mouth injuries.
  • Deer antlers (dried) may be too hard for some dogs and damage their teeth.
  • Raw hides, white in color, are traditionally processed with chemicals and glue and may cause digestive blockages.
  • Roasted/cooked bones, especially those purchased at the pet shops that are smoked and artificially flavored. 

Preparing Your Dog for Raw Meaty Bones

If your dog is new to raw food and raw meaty bones (RMB), here are a few things you need to understand. The gut microbiome needs time to adjust to digesting raw food, including RMBs. Also, the stomach acid needs time to adjust. The stomach acid pH of a kibble-fed dog is higher than that of a raw-fed dog. A lower, more acidic pH is required for digesting raw foods and bones.

Teaching Your Dog to Chew RMBs

There are different types of chewers among dogs. If your dog has not had the opportunity to chew on RMBs, you will need to observe him to determine his chewing style. undefined

We have identified five chewer types:

  • Gummers: We call dogs that lick and chew on the bone over time gummers. They take their time and wait for the bone to soften or dissolve before swallowing it.
  • Nibblers: Nibblers are dogs that take small nibbles here and there. They are not as interested in the bone as other chewers.
  • Methodical: A methodical chewer is engrossed in his bone. He is patient and tends to grind the bone into small pieces before swallowing it. 
  • Champion Chompers: These dogs are engrossed in their bones as they will continue to gnaw and chew for as long as it takes to consume the bone. They are not as patient as the Methodical chewer, but they are not gulpers either.
  • Gulpers: These dogs are not interested in a slow, methodical chew session! They will bite off chunks of bone and swallow them without grinding them into small pieces. 

All dogs, especially the Champion Chompers and the Gulpers, should be supervised during their chew sessions! Monitor the amount of bone they consume. Never leave your dog alone with a large bone, even if he is an experienced RMB chewer.

You can slow down the chomper or gulper by holding onto the bone with a chew holder, allowing you to control how long and fast your dog chews. You can also try different bone types.

Preparing the Gut Microbiome and the Stomach for Raw Food

The gut microbiome's performance depends on the quality of food that it processes. Dietary changes affect how the gut microbiome metabolizes protein, carbohydrates, and fat. If a dog has been fed a kibble-only diet, his gut microbiome will be required to make drastic changes when you switch to a raw diet.

The microbiota composition reflects the diet's ratio of macronutrients based on the body’s need to digest nutrients properly. You need to make incremental adjustments to your dog’s diet to allow the gut bacteria to adapt accordingly. The gradual transition strategy can take as little as one week or as long as six months, depending on your dog's reaction to the diet change. Typically, younger dogs will make this adjustment faster. See Transitioning To A Raw Diet (feedreal.com) for more information on transitioning your dog to raw food.

Changes over time allow the stomach acid pH to adjust. Although abrupt changes are not harmful, they may result in loose stools during the transition. During digestion, the stomach acid of a kibble-fed dog will be around 1.5, while a raw-fed dog’s pH will be less than 1, which is the equivalent of battery acid! Food stays in your dog’s stomach longer than in your stomach, as this is where most digestion occurs. This is another reason dogs can consume and digest RMBs.

Why We Are Taught to Never Feed Cooked Bones!

We were all taught never to feed our dogs any bones, especially chicken bones! But we were not told that it only applies to cooked bones. Pet parents are finally learning the difference between feeding cooked and raw bones. Dogs are genetically, anatomically, and physiologically adapted to eating raw bones as their ancestor, the wolf, does.

When bones are cooked at 160℉ or higher, the collagen, water, and nutrients are leached from the bones. During cooking, the Maillard reaction makes the bone brittle and more resilient to digestion. Chewing on cooked bones can result in broken teeth and mouth lacerations. The fragments can cause impaction, choking, constipation, bowel perforation, and peritonitis if swallowed.

Why Raw Bones Are Best

While these may not always be convenient for everyone to feed, raw meaty bones are covered with meat and connective tissue that aids in the digestion of the bones. They provide essential nutrients for your dog, mental stimulation, exercise for the jaw, and natural teeth cleaning. 

Dogs require calcium, which is best derived from whole bones. However, some dogs may have compromised teeth, and not everyone is comfortable feeding raw bones. When purchasing pre-made raw foods, raw-fed dogs often get their calcium from whole or ground-up bones or bone meal. Non-whole food alternatives include calcium supplements, which aren’t absorbed as well as their natural whole-food counterpart.

Methods for Drying Bones for Dogs

Other than cooking or roasting, there are two commonly used methods for processing bones used as treats, chews, or meal components for dogs: air drying, freeze-drying, and dehydration. Although these terms are often used synonymously, they are two very different processes. 

Drying is one of the oldest methods to preserve food against spoilage and microbial pathogens. Foods that are dried are still edible with their nutritional status intact. Drying aims to maintain nutrients and beneficial bacteria while eliminating harmful bacteria. Drying is achieved from the outside surface and then inward. Because the water in the bone is within the organic and inorganic matrix, it will slowly evaporate.

Air Drying

Air drying is the removal of moisture via evaporation to preserve the nutrients of the meat and connective tissue on it and to prevent damage or changes in the composition of the bone. Analysis from an independent laboratory showed that the air-dried bone retained a moisture content of 7% on average. With water content in the bone averaging 10%, it is clear that air drying does not rid the bone of all moisture. Nutritionally, air-dried bones are essentially the same as raw bones.

Air drying is a slow drying process at temperatures between 95°F-130°F. Although the air-dried bone can still splinter, the bones are never subjected to high heat over 160℉. The collagen and the connective tissue covering the outside of the bone are not destroyed by heat, so the bones, even when broken, still have a protective covering. The moisture within the matrix of the bone is minimally affected, allowing the bone to remain pliable and digestible. However, as with all bones, you must supervise your dog’s chew sessions.

Freeze-Drying

There are four stages in the freeze-drying process: pretreatment, freezing, primary drying, and secondary drying. Pretreatment can include concentrating the food to decrease its water content and adding compounds to increase stability. If the freezing phase is not done correctly, there is a risk of spoilage. To inhibit microbial growth, the freezing step uses temperatures ranging from -58℉ to -112℉. The two drying steps remove the ice particles and water from the food.

Freeze drying results in minimal structural damage to food with slight shrinkage and toughening of the tissues. However, the food's visible structure and nutritional content are retained, and freeze-drying deeply damages cell membranes. Overall, freeze-drying is an option for preserving food, but it is not the ideal choice for food and bones for oral health; air-dried or dehydrated bones are a better option for this purpose. Freeze-dried foods tend to crumble easily into powders and offer minor abrasion for scraping built-up tartar from teeth.

Dehydration

Dehydration involves drying the meat cuts and bones at 160°F or higher until at least 95% moisture is removed. Because a higher heat is used, naturally occurring nutrients, enzymes, amino acids, and vitamins are depleted, but not nearly as much as if they were cooked or roasted at a higher temperature. Dehydrated bones may be comparable nutritionally to raw bones. However, with the processing temperature sometimes exceeding 160°F, there may be some loss of vitamins, collagen, and moisture in the bone matrix.

Inherent Risk of Feeding Bones

There are inherent risks when feeding any type of bone. As a pet parent, you must be aware of these risks.

All bones splinter. No matter how the bones have been prepared or fed raw, they can splinter. The difference is in how the bones splinter. RMBs have connective tissue and some meat lining the outside of the bone, which protects against the sharp edges if there is splintering. 

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There is always a possibility of causing injury to the mouth or teeth. Teeth fractures can occur, primarily if you use the wrong bone type for your dog. As your dog ages, you will need to adjust the size and type of bone as the teeth of older dogs are more fragile. Do not provide recreational bones to dogs with fractured teeth or if they have had restorative dental work or crowns done. If feeding a raw diet, you can use a ground bone meal.

The aggressive chewers, the champion chewers, and the gulpers are also at risk for mouth and tooth injury due to their chewing style. Matching the type and size of the bone to your dog based on his habits can help minimize this risk. 

Your dog may experience GI upset when first introduced to RMBs, mainly because the gut is not prepared for raw food or your dog is not accustomed to chewing. If your dog is new to raw feeding and raw meaty bones, take precautions by preparing the gut microbiome. Link to the Gut Microbiome article

Canids are anatomically structured to digest the type of bones found on freshly killed carcasses. RMBs have a natural layer of skin or meat on the raw bone to aid digestion. But the bones you purchase at the pet shop may be roasted until completely dried out, devoid of any meat or connective tissue, and often contain preservatives. These bones are rendered indigestible.

Although choking is an inherent risk, it is rarely seen. The anatomy of the dog’s esophagus is structured to allow for bones to be swallowed as it is broader and thicker than our esophagus. However, flat-faced (brachycephalic) breeds, especially those with teeth missing, are known to have problems with choking. If you have such a breed, you can smash their bones to prevent them from swallowing large pieces.  

Feeding raw bones to your dog can be messy! Limit where your dog can gnaw on the recreational bones. Be aware that the floor can be slippery from the fat in the marrow bones. Clean and disinfect the surface well after each chew session.

Tips for Success

  • Raw meaty bones are the best bone to feed your dog because the meat around the bones aids in moisture, lubrication, and digestion. 
  • For edible nutritional bones, feed primarily poultry bones to meet calcium requirements. Feet are acceptable, but necks and wings should be used more frequently. The calcium percentage is lower in the bones of the feet, so prolonged use of them as the dog's only calcium source could result in a calcium deficiency. An additional calcium source, such as egg shells, is recommended.
  • You should offer your dog edible RMBs at least once a week for optimal dental health. Recreational bones can also be fed for dental health but are not fully digestible. It is best to discard the recreational bones once your dog has removed all the meat, connective tissue, and marrow.
  • Providing the RMBs when your dog's stomach is empty is best to allow optimal digestion. The more the bones are digested in the stomach, the less the chance of splinters entering the intestinal tract. 
  • Start with 15-20 minute sessions for dogs new to edible bones.
  • Always gather up the bones after each chew session.
  • Choose the right size bone for your dog. The concern is with giving bones that are too small. Giving your dog a small bone can become a choking hazard or get stuck in the upper palate of your dog’s mouth.
  • Always closely supervise your dog’s chew sessions. 
  • If you have more than one dog, you should separate them before feeding them raw meaty bones. Any dog can get possessive of a prized bone!
  • Dogs that are known resource guarders should be given raw bones very carefully. It could be dangerous for you to take the bone away at the end of a chew session without practicing the trade-it game or working up to this skill.
  • Precautions to take with marrow bones. 
    • Bone marrow contains a lot of fat. Take this into consideration when calculating your dog's caloric needs.
    • Do not use marrow bones for dogs that have been diagnosed with pancreatitis.
    • Too much marrow can also cause diarrhea in some dogs. 
    • If you are concerned with your dog's weight, remove the marrow before offering the bone to your dog.
  • Providing raw bones may not be practical for several reasons. Some pet parents are uncomfortable feeding raw bones due to bacterial contamination concerns or dislike the fresh, bloody smell. Having a supply of raw bones during travel or hectic days may also be problematic. Using air-dried bones is a viable alternative. 
  • Air-dried bones retain the nutritional value of their raw counterparts. They are easier to store and less messy to feed. People who are uncomfortable with providing raw bones are usually fine with air-dried bones. 

References