Raw Feeding- What’s the Evidence?

Raw feeding generates a lot of passion on both sides of the debate, with a lot of claims being made for its benefits and potential dangers. So what’s the evidence?

Rare or well done?

Pros:

  • Closer to a “natural diet”
  • Less residue as more digestible
  • Potentially better gastrointestinal and dental health.
  • Claims for health benefits such as improvement in coat and skin; elimination of breath, body, and faecal odour; improvement in energy, behaviour, and immunity; and a reduction in medical conditions including allergies, arthritis, pancreatitis, dental disease, and parasitism.

Cons:

  • If not sourced properly can potentially cause disease such as campylobacter, salmonella, clostridial disease and E. coli
  • Cats and dogs can develop subclinical infections with these organisms but still pose a risk to livestock and humans (especially children, older persons, and immunocompromised individuals.)
  • Create nutrient deficiencies if not done carefully
  • Tricky to store
  • Can be an unpleasant odour

No studies have examined differences in animals fed raw animal products to those fed any other type of diet (kibble, canned, or home cooked) with the exception of looking at the effects on digestibility. Typically raw meats (but not other uncooked foods like grains or starches) are slightly more digestible than cooked meat.
For more info, here is a nice review from JAVMA on the issue. Current knowledge about the risks and benefits of raw meat–based diets for dogs and cats. The take away points are:
  • A major problem in the discussion about potential risks and benefits of Raw meat Based Diets (RMBDs) is the paucity of good data from high quality studies.
  • A US study in 2001 revealed that all of the hom eprepared and commercial RMBDs tested (3 home-prepared and 2 commercial RMBDs) had multiple nutritional imbalances, some of which could have important adverse effects on the health of the animals
  • Although care is used during processing, meat from healthy food animals intended for human consumption may acquire bacterial contamination from the hide, feathers, or viscera during slaughter, evisceration, or processing and packing
  • Home-prepared raw diets were evaluated in 1 study in which 8 of 10 home-prepared raw chicken–based diets fed to pet dogs had positive results when cultured for Salmonella spp
  • commercial RMBDs and ingredients are covered by FDA regulations and can be recalled if contamination or other problems are detected, the feeding of contaminated home-prepared RMBDs that include foods intended for human consumption may go undetected because foodborne illnesses in dogs and cats are rarely tracked unless associated with human disease.
  • Some RMBD manufacturers currently use high hydrostatic pressure processing (also called high-pressure pasteurization) in an attempt to reduce risks of pathogens in commercial RMBDs. Although this process can reduce the numbers of many pathogens, it usually does not completely eliminate them, and bacteria and viruses differ in their susceptibility to this process
  • the perceived benefits of home-prepared diets may be reinforced daily to owners through a pet’s appetite or coat quality, nutrient deficiencies and excesses in adult animals are insidious and can lead to long-term complications if not detected and corrected. In young growing animals and pregnant or lactating animals, nutrient deficiencies and excesses can cause severe and sometimes life-threatening complications.

My Opinion

I believe the debate is overheated- the problems of feeding a raw diet are often overstated, as are the benefits of feeding a raw diet. I see pets doing extremely well (and badly) on both types of diet in the numbers I would expect if raw feeding was neither doing amazingly badly or amazingly well. However, I must temper this advice with a giant warning: raw feeding has been shown to cause food borne illness (see references at bottom). You MUST be extremely careful when sourcing, handling and cleaning up raw pet food. Please follow the tips in this article.

What are the professional opinions?

American Veterinary Medical Association

“The AVMA discourages the feeding to cats and dogs of any animal-source protein that has not first been subjected to a process to eliminate pathogens because of the risk of illness to cats and dogs as well as humans. Cooking or pasteurization through the application of heat until the protein reaches an internal temperature adequate to destroy pathogenic organisms has been the traditional method used to eliminate pathogens in animal-source protein, although the AVMA recognizes that newer technologies and other methods such as irradiation are constantly being developed and implemented.”

American Animal Hospital Association

“Feeding a raw protein diet no longer concerns only each individual pet, but has become a larger community health issue; for this reason, AAHA can no longer support or advocate the feeding of raw protein diets to pets.”

American College of Veterinary Nutritionists

“Safe and proper handling of raw foods is crucial for reducing the risk, but safety cannot be guaranteed. At this time, the vast majority of purported benefits of feeding raw foods remain unproven, while the risks and consequences have been documented. It is best to discuss the choice of feeding raw foods with your veterinarian so that an informed decision can be made with regard to your pet’s diet.”

US Food and Drug Administration

“In a two-year study spanning from October 2010 through July 2012, the FDA Center for Veterinary Medicine (CVM) screened over 1,000 samples of pet food for bacteria that can cause foodborne illnesses.1 (The illnesses are called “foodborne” because the bacteria are carried, or “borne,” in or on contaminated food.) The study showed that, compared to other types of pet food tested, raw pet food was more likely to be contaminated with disease-causing bacteria.”

US Center for Disease Control and Prevention

“raw food diets can make you and your pet sick, and for that reason CDC does not recommend feeding raw diets to pets.”

Tips on handling raw food

  • Thoroughly wash your hands with soap and water (for at least 20 seconds) after handling raw pet food, and after touching surfaces or objects that have come in contact with the raw food. Potential contaminated surfaces include countertops and the inside of refrigerators and microwaves. Potential contaminated objects include kitchen utensils, feeding bowls, and cutting boards.
  • Thoroughly clean and disinfect all surfaces and objects that come in contact with raw pet food. You can also run items through the dishwasher after each use to clean and disinfect them.
  • Freeze raw meat and poultry products until you are ready to use them, and thaw them in your refrigerator or microwave, not on your countertop or in your sink.
  • Carefully handle raw and frozen meat and poultry products. Don’t rinse raw meat, poultry, fish, and seafood. Bacteria in the raw juices can splash and spread to other food and surfaces.
  • Keep raw food separate from other food.
  • Immediately cover and refrigerate what your pet doesn’t eat, or throw the leftovers out safely.
  • If you’re using raw ingredients to make your own cooked pet food, be sure to cook all food to a proper internal temperature as measured by a food thermometer. Thorough cooking kills Salmonella, L. monocytogenes, and other harmful foodborne bacteria.
  • Don’t kiss your pet around its mouth, and don’t let your pet lick your face. This is especially important after your pet has just finished eating raw food.
  • Thoroughly wash your hands after touching or being licked by your pet. If your pet gives you a “kiss,” be sure to also wash your face.

References

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