Raw diets for dogs – natural or harmful?

There is a growing trend to feed raw diets to dogs and many of my clients do indeed follow these regimens and feel that their dogs are healthier as a result.  I do not wish to condemn such choices but do want to offer some words of caution as there is another side to the story.

The usual argument put forward for the feeding of raw diets is that their wild counterparts would eat raw food.  However, we must consider that the domestic dog has evolved away from the wild wolf over several thousand years meaning that they do not necessarily have the same resilience as they once may have done or that of a modern day wild dog such as a wolf, hyena or dingo.  Darwinian evolution selects for hardy individuals that are well adapted to survive the demands of the wild environment.  This equates to animals whose gastrointestinal systems are tolerant of whatever the animal may ingest.  One curious feature of such evolution is that dogs are able to trigger their vomiting reflex much more readily than humans so that they can void their stomachs if they have consumed something noxious which they cannot deal with, or if they wish to reproduce the food they have eaten so that their young may be nourished.

People often ask me what a wild dog would do if it developed diabetes, cardiac disease or any number of other examples.  The answer is simple – it would not survive.  Therefore, the genes coding for these illnesses would not be passed on and gradually, over many years, the population would become less susceptible to the disease in question.  The pressures of the environment naturally select for those most likely to survive it.

However, take the dog out of the environment and start to domesticate it and the reverse will start to happen.  Certainly in modern veterinary medicine, there is the means to support many diseases that would have hitherto been fatal to the wild ancestor.  Such genes may be passed on and the population devolve from the wild relations.

Further genetic diversity is introduced by man, who selectively breeds for certain desirable traits, such as ability to guard the cave or, in the modern world, have a certain conformation.  When one breeds to perpetuate good (or sometimes what most people would consider not so good) traits, characteristics and appearances, it is inevitable that unwanted genes will also come through.  There are many diseases which are seen in particular breeds of dog as a result of this.

So can modern domestic dogs cope with raw food?  Undoubtedly many will, but we do see a number of patients where they cannot and develop diarrhoea as a result.  They may simply be unable to digest the food in its raw state or they may actually acquire the organisms Salmonella and Campylobacter.  Either way, the inflammation that develops within the bowel can become persistent even after the initial trigger has gone and this is a condition we see frequently called inflammatory bowel disease.  However, it should be acknowledged that anything causing inflammation of the intestines and diarrhoea may lead to this, so the problem is not confined to raw diets.

A further, perhaps more significant, concern is these organisms colonizing the dog’s intestine without signs of diarrhoea as this poses a risk to the owner of contracting them from their dog and becoming ill themselves.  Children, elderly and immunosuppressed people would be most at risk from this.

Everyone must make their own decisions as to what is right for their pet, but these words should offer a note of caution that with every perceived advantage of raw food there will be potential pitfalls.