Saturday, March 15, 2008

It's A Dog's Breakfast - Part 4: What's In It For Fido?

We hear a lot of claims from promoters of raw meat diets about the nasty ingredients in kibble and canned pet foods – binders, stabilizers, meat from diseased animals, corn and other grain fillers. In fact, many dog foods, especially the lower-priced products, leave much to be desired. But what, exactly, is in a “raw food diet”? Is it more nutritious than the best commercial “cooked” diets? Is it safe?

The BARF Diet
Dr. Ian Billinghurst is a pioneer in the field of raw pet foods. He published his first book, "Give Your Dog a Bone: The Practical Commonsense Way to Feed Dogs for a Healthy Life" in 1993.

Dr. Billinghurst's book introduced many pet owners to the concept of the "Biologically Appropriate Raw Food" diet, which was an attempt to mimic the natural diet of the dog's wild ancestor – the wolf. The original BARF diet comprised raw meaty bones (usually chicken wings and backs, but sometimes beef, lamb or wild game, including venison), raw eggs, pureed raw fruits and vegetables, and the occasional dollop of yogurt.

The BARF diet, while embraced by some dog owners, was daunting to others. Several years ago, Dr. Billinghurst simplified BARF by introducing a commercial product line, consisting of frozen patties, which is sold through a web site named BARFWorld. The line of products includes "Beef Offal", "Beef Tripe", and "Chicken and Bone Mince" patties. BarfWorld also sells nutritional supplements and "Fruit and Veggies Nuggets".

In 2004, BARFWorld announced that it would be conducting nutritional research “...on the best possible means of feeding our companion animals,” and asked for volunteers to participate in the study. Twenty-eight dog years later, we’re still waiting for the first word on this study.

Raw Meaty Bones Diets
Dr. Billinghurst isn’t the only advocate of raw feeding. At about the same time that he introduced the BARF diet, another group of Australian veterinarians began to promote a different Raw Meaty Bones (RMB) diet. Other raw diet disciples have chimed in with their own variations. All of the diets are built on a foundation of raw poultry or raw meaty bones.

A Balanced Diet?
A supporter of homemade (raw or cooked) diets said in 2003,
“... feeding home-prepared cooked or raw diets has not been proven to control medical problems, based upon prospective, double-blind, statistically significant clinical trials.”
This is still true in 2008. I have searched the scientific journals using PubMed, a search engine service of the U.S. National Library of Medicine, and have not found a single report of even a small, prospective feeding trial.

One study, published in 2001, attempted to address the nutritional content of raw diets. It compared three homemade and two commercial raw diets against the guidelines recommended by the Association Of American Feed Control Officials (AAFCO). The study was inconclusive for several reasons:
  • calculation errors, especially of the levels of vitamin D in the diets, forced the authors to publish a correction;
  • the study comprised just a single sample of five different diets - not enough to account for day-to-day variation, especially of the homemade diets; and
  • its conclusions relied strictly on lab analysis, which cannot predict the extent to which the nutrients can be digested and absorbed.
RMB = Really Microbiologically Bad?
Many pet owners who are considering switching to a raw diet, especially one based on poultry, worry about Salmonella and other food poisoning bacteria. And they have good cause for concern. According to the USDA, 45% of raw ground chicken and 11.4% of whole broiler carcasses in the US are contaminated with Salmonella.

I searched the scientific literature and found three articles that specifically analyzed raw meat diets for bacterial contamination. These studies were limited in size and scope, but the results were consistent.

1. Joffe, D.J. and D.P. Schlesinger. 2002. Preliminary assessment of the risk of Salmonella infection in dogs fed raw chicken diets. Canadian Veterinary Journal, vol. 43 (June), pp. 441-442.
In this preliminary study, the authors tested 10 samples of homemade BARF diets for Salmonella. Eight of the 10 samples contained Salmonella, as did the feces of 3 of the 10 dogs that had been fed the BARF diet.

2. Weese, J.S., et al. 2005. Bacteriological evaluation of commercial canine and feline raw diets. Canadian Veterinary Journal, vol. 46 (June), pp. 513-516.
This study examined samples from 25 commercial raw diets. Fifteen of the 25 samples contained Escherichia coli (but not E. coli O157:H7), 5 samples (20%) contained Salmonella, and 5 contained Clostridium perfringens, another food poisoning bacterium.

3. Strohmeyer, R.A., et al. 2006. Evaluation of bacterial and protozoal contamination of commercially available raw meat diets for dogs. American Veterinary Medicine Association Journal, vol. 228, no. 4, pp. 537-542.
In this yearlong study, 240 samples of commercial raw meat diets were examined for E. coli, Salmonella and Campylobacter. The researchers did not find any Campylobacter, but detected E. coli in just about every sample, and Salmonella in 17 of the 240 samples.

Many producers of commercial raw food diets acknowledge that their products may contain harmful bacteria. Some, such as Nature's Variety, provide their customers with handling instructions to minimize the risk of transmission.

But one raw pet food company has gone several steps farther. To find out more, watch for Part 5 of this series, “One Company’s Approach”, which will appear on Monday, March 17th.



  2. anonymous' links preach to the choir quite well. I've read most of those articles about "myths" but none of the myths point to any solid evidence.

    There is an assumption that the lovely SOUNDING "fresh, whole, raw" is superior to kibble...but without any evidence.

  3. Look at this in terms of people.Does your doctor tell you to eat as many processed foods as you can, or does he tell you to eat as many fresh, unprocessed foods as you can? Commonsense tells you which is better, do we need peer reviewed studies to tell us that? The studies on dog nutrition are done by kibble manufacturers. What incentive would they have in doing a study that showed raw was better than kibble?

  4. Anonymous,

    Actually I'm a Registered Dietitian so my doctor doesn't bother telling me how to eat, she knows better ;-)

    There isn't much data to support a RAW human 100% unprocessed diet either. Yet there IS plenty of research to support COOKING food for humans (veggies, grains, legumes, meat, etc) do FINE with cooking.

    If there are vets, vet students, animal nutrition experts, researchers, raw food companies (yes there ARE companies who could benefit from proving raw food is better and others who need to research things for a living so why not this?) who believe in RAW...there are plenty of ways to find funding for such a study.

    If there are ways to fund research that compares the diets of people in various countries, there are ways to fund research to compare diets of raw vs. kibble fed dogs.

    I don't think there is anything WRONG with feeding YOUR dogs raw based on common sense as you see it. BUT that does NOTHING to prove or support advice for OTHERS to do the same. What one person sees as common sense is not a basis by which to say "X is a myth" as the articles you listed claim. When you claim X is a myth or Y is incorrect or Z is must go by actual evidence...not just "common sense."

    Wolves and wild dogs would also likely chase their prey, catch and eat it...I'm not gonna let my dog chase bunnies, squirrel and other "game" for the sake of letting him live out his life in a more "natural" way. So "natural" for a wolf or wild dog is not a convincing argument.

    The proof will be when someone has the guts to actually do a comparative study of raw vs. kibble fed dogs. It can be done in all sorts of ways: mailed surveys, online surveys (MUCH cheaper), etc. It's at least a start for conversation.

  5. A.P. - as a registered dietitian I will assume that you do not encourage people to eat highly processed food as the main ingredient of their diet. I will further assume that you do not suggest they eat bird seed, grass, or raw meat. If, however, you were suggesting diets to sparrows, antelope or tigers, you would have to change your dietary advice. No matter how uch we love our pets - they are not tiny humans. They have vastly different nutritional needs. I would hope you don't suggest people eat raw meat. I would also hope you don't suggest carnivores start eating tofu & bird seed.

    Finally, as a food professional you should realize that proper food handling is just as important as the type of food. No matter what you suggest as a diet people will get sick if they do not practice proper hygiene.

    I'm now beginning to suspect the author works for a pre-processed raw diet manufacturer.

  6. a.p., as an R.D working amongst the public for 9 years now, I can say that I don't agree with you that humans 'do fine' with cooked foods.Many are overweight, suffer from many health problems from eating poor, mostly processed diets,and gluten from grains is reeking havoc with many of their systems.MANY humans would benefit greatly from the addition of more whole, raw foods to their diets.
    Dogs are following the same path.The obesity problem with dogs has even caused a diet pill for them to come out.It maybe anecdotal evidence, but visit a few raw forums and see the number of dogs whose health has changed for the better on a raw diet.Chronic ear infections gone, old dogs that act young again, oral heath much improved, on and on the list goes.

    I would also say that while a raw diet isn't difficult,it does take extra shopping time, prep time, nutrition studying,and extra storage space (freezer) to be able to buy in bulk. Yet people see good enough results that they go through this to feed this type diet.If my dog did this well on kibble, why go through all this hassle?
    It was much easier picking up a bag of Evo, but I wouldn't go back.

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  9. If humans are doing fine on what they are eating why is obesity and childhood obesity and their complications at an all time high? Why is coronary disease now the biggest killer of women and why are certain digestive tract cancers on the super drive rise? Why are neurological diseases exploding like fire and the average consumer can't read a label to save his life. Why is the FDA passing new laws about labels every year and why can fatty caloric food be marketed as fat free and calorie free?

    The answer is all is not well and most people aren't eating healthy and could stand a good dose of a more natural more raw diet. I don't think a totally raw diet is appropriate. But to compare omnivores like us to animals like dogs and cats and other companion animals is ridiculous. The hunting bunnies comments shows how emotional the entire issue is.

    There isn't going to be a rational study about kibble and raw in the short term because of legit funding. The fight about over-vaccinating for rabies and other diseases has been ongoing for years despite much research there just aren't enough dollars. When you have people like Entis here stirring the pot all the water gets muddy and less happens.

    Stop the verbal misinformation and terrorism and much more might get accomplished.

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  13. As a courtesy to all readers, I request that everyone identify himself or herself at least with some random initials so that a train of thought can be maintained. I have not blocked Anonymous posting, but I have enabled my moderation option and will block any individual posts that do not contain at least a minimal level of identification.

    Phyllis Entis, MSc., SM(NRM)


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