The AVMA recently adopted a policy position against raw meat diets for pets. Their reasoning is wrong and their science is unfounded. Here is my reasoning on why AVMA (as well as the AAHA, which adopted the same policy almost as soon as AVMA voted on theirs) is wrong.

The AVMA’s Financial Conflict of Interest

According to the AVMA itself, this policy is the result of a suggestion by the Delta Society (now “Pet Partners”), which banned the feeding of raw-meat-based diets to therapy dogs in its programs in 2010. The Delta Society’s ban appeared to be instigated by a board member who, at the time, was in charge of Marketing for Nestlé Purina. Additionally, Purina donated $400,000 to the Delta Society (the largest donation ever received by the Delta Society). Purina also promotes the Delta Society on its website. The Delta Society’s vests (those worn by therapy dogs) were reportedly redesigned to include the Purina logo.

Many people (including me) believe that this policy decision was financially and politically motivated. And indeed, pet food companies provide a great deal of funding to AVMA, albeit indirectly; for example, through lecture sponsorships, receptions, exhibitor fees, and “goodies” at the annual AVMA Convention. They also donate directly to the AVMA Foundation.

In 2008, the AVMA created a four-year “AVMA Platinum Partner Program” with Hill’s Pet Nutrition. The AVMA got more than $1.5 million from Hill’s, in exchange for promotional favoritism. This relationship is a clear conflict of interest with the proposed policy. Moreover, it may violate laws governing non-profit organizations. Amazingly, in perhaps the oddest computer “error” ever made, the article from the AVMA’s Journal announcing this deal-with-the-devil somehow got “lost” in the recent update to AVMA’s website, as did other pertinent pages.

The Role of the AVMA

It is not the AVMA’s role to create a policy dictating how to practice medicine, or what foods veterinarians sell or recommend to their clients.

If AVMA wishes to educate veterinarians about the risks/benefits of any diet (or pharmaceutical or procedure), a JAVMA editorial would be appropriate. A policy that specifically vilifies a large segment of the pet food industry comprising dozens of companies is injudicious, not to mention potentially libelous. No other AVMA policy targets a specific company or group of companies by recommending that vets not use or recommend specific products. 

Hundreds, if not thousands, of veterinarians use and recommend raw diets for their patients, and have done so for many years. Many veterinarians consistently find that animals’ health improves on such diets. In fact, a researcher for a large pet food company once told me that the company had studied raw diets, and cats do much better on raw meat than on cooked or processed diets.

For AVMA to create a policy that makes a significant number of their members wrong appears to be a political stab in the back to those conscientious practitioners who have studied the issue and chosen raw diets as the best option for their patients. Moreover, it directly interferes in the sacrosanct veterinarian-client-patient relationship.

AVMA Policy

The AVMA’s policy is redundant and unnecessary. The FDA has already published a guidance document for industry concerning raw food diets. Raw diet manufacturers are also required to comply with the exact same AAFCO guidelines and the exact same manufacturing standards as any other pet food. 

AVMA Influence

The AVMA correctly states that it is not “banning” or “regulating” raw pet foods—but it is using its influence in a highly political and unethical manner. The AVMA has about 80,000 members, and it is doing its best to segregate and drive out those with a holistic mindset. This is just another nail in the coffin the AVMA has long been building for holistic and integrative medicine, in order to satisfy its largest donors: Big Pharma and Big Pet Food.

The Role of the AVMA

Despite the AVMA’s professed support of evidence-based medicine, this policy is completely unsupported by the evidence. The AVMA cites just six studies; and even those hand-picked studies—apparently the best AVMA could find–don’t actually support their position. Lets take a look.

AVMA Claim of “Facts” #1

Claim: Scientific studies have shown that raw and undercooked protein can be sources of infection with Salmonella, Campylobacter, Clostridium, E. coli, Listeria monocytogenes, and enterotoxigenic Staphylococcus aureus. These infections can sicken pets and pet owners alike, and can be life-threatening.

The U.S. meat supply is contaminated with many bacteria. Uncooked meat does carry a risk of bacterial contamination.[i] We are not arguing that point; in fact, we gladly stipulate to the fact that a lot of meat has a lot of organisms that can and frequently do contaminate it.

But which, if any, of these organisms presents a real risk to pets, people, or both?

Let’s take the bad guys named by AVMA, one by one:

Salmonella

The first study cited by the AVMA states that “Salmonella was isolated from 80% of the BARF diet samples (P < 0.001) and from 30% of the stool samples from dogs fed the diet (P = 0.105). Dogs fed raw chicken may therefore be a source of environmental contamination.”[ii]

This is not the whole story. This study looked at only 20 dogs (10 raw-fed, 10 control), and of the 3 positive stool samples, only 1 was from a dog whose food contained the same serovar; another was from a dog whose food contained a different serovar, and the last was from a dog whose food tested negative. No dog or human illness was reported, despite confirmed contamination of the food. This has consistently been the case with nearly every analysis of raw foods: they contain pathogens, but nobody is getting sick.

The second AVMA-cited study states that 95% of human Salmonella cases are due to eating contaminated food. The authors speculate that some number of these could be due to contact with dogs or dog food, and cites data from 1987, which estimated that 1% of human salmonellosis could be due to contact with pets (but not pet food). The authors conclude, “To date, raw pet foods have not been associated with salmonellosis in humans.”[iii]

The literature supports the fact that zoonotic transmission of Salmonella from pets to people is extremely rare. A 2011 review found only a single U.S. case of transmission of Salmonella from a dog to a human since 1974.[iv] (In that case the human had let the dog eat broth that had been standing, unrefrigerated, for days.)

Research suggests that up to 36% of dogs and 18% of cats are asymptomatic carriers of Salmonella.[v] The possible source of the organism was not discussed, but may include the environment as well as diet, which of course was most likely to be heat-processed pet food.

Dogs and cats themselves appear to be quite resistant to illness due to this ubiquitous bacteria. There has been only one report of illness in cats possibly linked to Salmonella, although in that case one cat was positive for a different serotype than the one in the food, and Salmonella was not proven to be the cause of either cat’s illness. Owner neglect was clearly the primary factor in their deaths.[vi]

The evidence clearly shows that Salmonella, as the most feared pathogen of raw meat diets, is not a significant threat to human or animal health.

Campylobacter

The AVMA’s reference on Campylobacter examines the public health risks of feeding raw diets to dogs.[vii] As evidence, this review cites a Hungarian study that included free-roaming dogs with access to aborted livestock fetuses and raw poultry that were found to be contaminated with Campylobacter. One person became sick, but it is unknown whether or not he handled infected tissues.

Campylobacter, a common pathogen of wildlife, livestock, and poultry, is also zoonotic. However, research suggests that only a “small proportion of human infections are acquired from dogs…usually [from] puppies that are themselves suffering from diarrhoea. Only four infections associated with cats (all kittens with diarrhoea) have been reported.” The study concluded that dogs and cats are unlikely to be the source of human infections.[viii] Phylogenetic analysis of cases, which are strongly seasonal, suggests that most human cases of campylobacteriosis are most likely due to water contamination.[ix]

One study on Campylobacter states that “…if a person and a pet have concurrent campylobacteriosis, the veterinarian must consider whether they both obtained it from some other common source (for example, food or water) or if the pet obtained it from the human being.” The authors conclude that dogs and cats are unlikely to be the source of human infection.[x]

The evidence clearly shows that Campylobacter, as the next most common pathogen of raw meat diets, is not a significant threat to human or animal health.

Toxoplasma

Regarding this protozoal parasite, which may encyst in raw meat, researchers concluded that, “Because of their fastidious nature, the passing of non-infective oocysts, and the short duration of oocyst shedding, direct contact with cats is not thought to be a primary risk for human infection.”[xi] Given that about 41% of U.S. cats are allowed outdoors where they can readily hunt and consume prey, it is unlikely that raw food diets significantly increase the risk.[xii] The primary cause of human toxoplasmosis comes from humans themselves consuming raw or undercooked meat, milk, or shellfish.[xiii] Having 3 or more kittens was also a risk factor, but a sick litter of kittens also implies an outdoor cat–and irresponsible owners.

In Canada and other countries, Toxoplasma is a common contaminant of pork. However, raw diet proponents do not recommend feeding uncooked pork, and no raw diet studied to date has contained pork.

The evidence shows that Toxoplasma in raw meat diets is not a significant threat to human or animal health.

Clostridium perfringens

These bacteria, commonly found in decaying vegetation, are common and contagious causes of gastroenteritis in dogs and cats. Infections are usually self-limiting. The study cited by AVMA to support its claim that Clostridia in meat is a significant health hazard states, “the exact relationship between C perfringens infection and gastroenteritis in dogs is not clear.” It also states that if anyone handled that meat–and did not wash their hands–they probably would have become infected. Another study reported, “No associations between C. difficile, MRSA, or VRE and consumption of raw meat were detected.”[xiv] So not only is C. perfringens not a serious issue, but neither is the more pathogenic C. dificile.

Therefore, the evidence shows that C. perfringens in raw meat diets is not a significant threat to human or animal health.

E. coli

The U.S. meat supply, particularly beef, is highly contaminated with E. coli. The organism is also ubiquitous in the environment. People commonly carry it. In the vast majority of cases, E. coli is a harmless commensal of the gastrointestinal tract. A study that looked for a pathogenic strain, E. coli O157, in raw-meat fed dogs and their environment found none. [xv]

The evidence shows that E. coli in raw meat diets is not a significant threat to human or animal health.

Listeria

The literature reports listeriosis in one dog, source unknown. Virtually all human listeria is due to consuming contaminated foods such as meat, cheese, and milk. However, contamination occurs during processing of these foods for cold cuts, hot dogs, and similar products. There is no evidence that any human or pet has ever has contracted Listeria from fresh, raw meats.

There is no evidence to suggest that Listeria in raw meat diets is a significant threat to human or animal health.

Staph aureus

The AVMA-cited study on this topic states, “Dogs are also susceptible to illness caused by Staphylococcus aureus and Bacillus cereus.

These toxin-producing organisms can be found in raw meat and commercially prepared foods and may proliferate and produce toxins if the food is allowed to incubate before feeding. Many idiopathic digestive upsets of dogs may be related tobacterial growth in moist foods put out for dogs and left for many hours before they are eaten.[xvi] Many people mix water, broth, or other liquids with dry foods. This is clearly risky.

Unpublished data cultured B. cereus from every dry dog food tested; that study’s author attributes most cases of “garbage gut” to B. cereus, not Staph.[xvii] The AVMA’s source did not separate out the two species.

There is no evidence that Staph aureus in raw meat diets is a significant threat to human or animal health. 

AVMA Claim of “Facts” #2

Claim: Unless a raw protein product has been subjected to a process that eliminates pathogens that can make pets and people ill, it poses a significant public health risk to both pets and pet owners.

On the contrary, pet foods that have been subjected to a process that eliminates pathogens are far more likely to make pets and people ill. Dry food is heat-processed twice: first, the meat ingredients are rendered (a slow-cooking process that boils animal parts for hours at 250^oF), and then again during extrusion (a quick process, but done at extremely high pressure and temperature).

A long record of problems with processed pet food provides more than enough proof.

Salmonella

Since March, 2012, 49 people and uncounted pets have become ill due to Salmonella contamination of their heat-processed dry commercial pet food. The recall of potentially contaminated food entangled 14 brands of food. 

A recently published review highlights the risks associated with heat-processed commercial pet foods: “There were 11 major pet food recalls in the United States between 1996 and 2010 that were due to chemical contaminants or misformulations: 3 aflatoxin, 3 excess vitamin D3, 1 excess methionine, 3 inadequate thiamine, and 1 adulteration with melamine and related compounds and an additional 2 warnings concerning a Fanconi-like renal syndrome in dogs after ingesting large amounts of chicken jerky treat products.[xviii]  (Note that the hundreds of brands and flavors included in the melamine-related recall are included as a single incident.)

But this review, published in March, 2012, is not up to date. Between May 1 and August 1, 16 brands of commercial dry pet food were recalled due to Salmonella, one due to thiamine deficiency, one due to a “strange odor,” and one due to chunks of blue plastic in canned dog food. 

Aflatoxin

Heat-processed pet food is to blame for many cases of illness and death in pets. Not only bacteria, but fungal toxins may be present in dry, grain-containing pet food. Several large pet food recalls have involved moldy grain, particularly corn. Only dry foods were involved. In a 1995 recall, dozens of dogs were sickened by vomitoxin in the food. Aflatoxin was responsible for about 25 dog deaths in 1998, and 100 more in 2006. In 2011 alone, 15 different brands of dry dog food were recalled due to aflatoxin. (Source: FDA) Aflatoxicosis has a morbidity rate of nearly 70% in dogs.[xix]

Commercial pet foods are responsible for thousands of deaths and tens of thousands of cases of illness in pets (and dozens of cases of human illness). This, of course, does not include a host of other directly food-caused illnesses such as food allergies and intolerances and obesity (with all its sequelae). In terms of morbidity and mortality, raw meat diets aren’t even on the radar.

Positive Aspects of Raw Meat Diets

Now, let’s look at the positive side of raw meat diets. We won’t belabor the point with the thousands of stories told by veterinarians and pet owners alike of near-miraculous cures when a pet’s diet was changed from heat-processed to raw. But there are actually multiple studies showing that raw meat diets for dogs and cats are more digestible than heat-processed foods. Here are a few of them:

• Beloshapka AN, Duclos LM, Vester Boler BM, et al. Effects of inulin or yeast cell-wall extract on nutrient digestibility, fecal fermentative endproduct concentrations, and blood metabolite concentrations in adult dogs fed raw meat-based diets. Am J Vet Res. 2012 Jul;73(7):1016-23.
• Kerr KR, Vester Boler BM, Morris CL, et al. Apparent total tract energy and macronutrient digestibility and fecal fermentative end-product concentrations of domestic cats fed extruded, raw beef-based, and cooked beef-based diets. J Anim Sci. 2012 Feb;90(2):515-22.
• Murray SM, Patil AR, Fahey GC, et al. Raw and rendered animal by-products as ingredients in dog diets. J Anim Sci. 1997;75:2497-2505.
• Vester BM, Burke SL, Liu KJ, Dikeman CL, et al. Influence of feeding raw or extruded feline diets on nutrient digestibility and nitrogen metabolism of African wildcats (Felis lybica). Zoo Biol. 2010 Nov-Dec;29(6):676-86.

What Should the AVMA Do Instead?

Good client education and an emphasis on safe meat-handling procedures is adequate to prevent human illness related to raw (or any other) pet diets.

Hundreds of veterinarians recommend raw meat diets, and dozens of companies make them, but nobody recommends abandoning all reasonable safe meat-handling principles when feeding them.

It is absolutely true that raw meat has a high likelihood of bacterial contamination. But using raw meat for pet food carries no more risk than preparing meat loaf for your kids: safe, as long as one uses normal precautions.

As one study on zoonotic diseases states, “The transmission of pet-borne zoonoses is complex and usually requires close contact between susceptible human beings and animals or their excretions. Such contact frequently involves lack of common sense and gross breach of sound hygienic practice.”[xx]

With specific reference to Campylobacter, but broadly applicable to all potential pet-food related zoonoses, another researcher stated, “The application of simple hygienic measures should prevent such infections.”[xxi]

The AVMA should undertake a campaign that truthfully assesses the risks from all pet diets, and encourage members to fully inform their clients about the risks and benefits of every type of food, with an emphasis on safe handling and general cleanliness.

In conclusion, the proposed AVMA policy is illogical, inappropriate, and not even remotely evidence-based. Nevertheless, AVMA voted to approve it.

Fortunately, there is a backlash, and it appears to be in favor of raw food. It is also reinforcing the (IMO entirely correct) perception that the AVMA is nothing but an antiquated, intolerant, narrow-minded gang of egotistical, self-righteous politicians and lobbyists.

References