Bacteria: science fact v. science fiction

Jonathan Self

I am quite convinced that Lord Lucan is dead, the Americans landed on the moon and that reptilians do not control the world’s governments (although it might be better if they did).

But just because I am not a conspiracy theorist doesn’t mean that conspiracies don’t exist. I firmly believe that the big pet food manufacturers are actively plotting to prevent the growth of raw feeding.

Why would they bother? First, raw fed dogs are healthier and live longer lives than dogs fed kibble and canned food. Second, kibble and canned food is hugely profitable, whereas quality raw food is not.

How are they hoping to achieve their (evil) objective? By twisting scientific fact and turning it into scientific fiction. One clear example of this is the misinformation they spread about so-called harmful bacteria.

In this week’s Alternative Dog article, I look at how the big pet food manufacturers are actively spreading misinformation about Salmonella and how it is actually the bacteria on kibble and canned food that poses the real risk to dogs and their human companions.

The background

One of the criticisms that is levelled against a species-appropriate or raw food diet for dogs (and cats) is that the meat used poses a risk to human health because it harbours potentially harmful bacteria. As all raw meat can harbour potentially harmful bacteria, this argument can appear to have some validity. However, providing you observe proper hygiene procedures the risks from feeding a species-appropriate diet are negligible. 

Dry and canned pet food is not safe

Perhaps the first thing to be aware of is that dried and canned pet food frequently harbours Salmonella, E.coli and other harmful bacteria.According to the US Food and Drug Administration (FDA) in the last decade there have been more than 20 largescale dry and canned pet food recalls due to Salmonella contamination. These involved major brands such Hill’s and Purina. Moreover, there have been over 800 cases of dry dog food being linked to Salmonella contamination in humans (Schottea et al. 2007, Reinberg 2008, Behravesh et al. 2010, Imanishi et al. 2012).

The Association for The Truth in Pet Food carried out extensive research into dried and canned dog food in 2015 and found that every single one of the 11 popular brands tested contained bacteria that was linked to human illness or death and/or that was resistant to antibiotics. It is clear that dry and canned pet food is not free from risk and it is wrong to present it as a safe alternative.

Bacteria is not a dirty word

It is important to understand that bacteria, per se, is far from being harmful to human health. In the right places and the right amounts, bacteria are very valuable to our health and wellness. We need it to stay healthy. For example, the bacteria on our skin, in our airways, and in our digestive system are the first line of defence against foreign invaders (pathogens) that can cause infection and other problems. Bacteria also act as ‘tuning forks’ for our body’s immune system, making sure it’s pitched just right. It protects us against illness and disease. Crucially, by having good bacteria in your body, bad bacteria doesn’t get a chance to grow and cause health issues. If you would like to read more about the role of bacteria in human health try Tim Spector’s bestselling book: ‘The Diet Myth: The Real Science Behind What We Eat’. (As an aside, I was at school with Tim and he was pretty brainy back then).

Some scientists now believe that the obsession with killing bacteria in the home and on our bodies is damaging human health. All those antimicrobial wipes, gels, hand sprays &c. may be doing us as much harm as good. 

Evaluating the enemy

So, which food borne bacteria do humans need to be wary of? The World Health Organisation (WHO) lists the main risks as being Salmonella, Campylobacter, and Enterohaemorrhagic Escherichia coli. WHO goes on to point out that antimicrobials, such as antibiotics, are essential to treat infections caused by bacteria. However, their overuse and misuse in veterinary and human medicine has been linked to the emergence and spread of resistant bacteria, rendering the treatment of infectious diseases ineffective in animals and humans. Resistant bacteria enter the food chain through the animals (e.g. Salmonella through chickens). Antimicrobial resistance is one of the main threats to modern medicine. Almost without exception pet food is made using meat from animals that have been routinely given antibiotics. This is one of the reasons why Honey’s Real Dog Food uses ethically reared meat (certified organic, wild and free range) from animals that have had no (or very limited exposure) to antibiotics.

The critics’ concerns

Those who are against species-appropriate feeding highlight three different risks:

  1. The risk of coming into contact with harmful bacteria when the food is being prepared and served.
  2. The risk to the dog or cat from consuming harmful bacteria.
  3. The risk that the dog or cat will transfer the harmful bacteria to humans by various methods including their mouths (licking), their fur (stroking) or their excrement (poo!).

How valid are these concerns?

To begin with, there is a potential risk from harmful bacteria when any food is being prepared and served. There can be harmful bacteria on raw meat, raw vegetables, raw salad and raw fruit. The risk is higher on raw meat but Google ‘Salmonella on fruit or salad’ and dozens of stories come up about Salmonella found on melon, salad leaves and so forth. However, if the correct procedures are followed (see separate box) then the risk of becoming ill as a result of coming into contact with species-appropriate raw food are negligible. Moreover, as explained elsewhere in this fact sheet there is a risk from dry and canned dog food, too.

What about the effect of potentially harmful bacteria on a dog? Dogs are omnivores but they have the same physiology as carnivores. Their primary source of nutrition comes from prey and, as they can’t cook, they consume this raw. Their digestive system is capable of eating raw food and the potentially harmful bacteria it harbours without ill effect. To quote Dr Conor Brady, founder of Dogs First ( ‘A dog’s lick is anti-bacterial. In the past, armies and monks have used dogs to clean their wounds. There’s an old French saying that goes “there’s nothing as clean as a dog’s lick”.’ Dogs actually have several defence mechanisms against harmful bacteria including their saliva, which contains lysozyme (extremely hostile to micro-organisms), their acidic guts (gastric juices of pH 1, the same pH as battery acid) and their short digestive tracts (anything potentially damaging is excreted with great speed).

Finally, what about the risk of harmful bacteria being transferred from a raw fed dog to a human via licking or stroking or through contact with excrement? It is certainly true that some dogs do have harmful bacteria in or on their bodies but this is by no means restricted to raw fed dogs. The idea that raw fed dogs are spreading harmful bacteria every time they shake themselves is not borne out by the facts. To the best of our knowledge there has been only one reported case anywhere in the world of a toddler who is believed to have become ill after coming into contact with Salmonella from a raw fed dog. However, we don’t know that the salmonella came from the food (the dog could have picked it up out on a walk, for example) or that the toddler contracted it from the dog (Salmonella is to be found in lots of places!).

The Honey’s Poo Test

We tested faeces (okay, okay, poo) belonging to 19 Honey’s fed dogs to see what we would find and we discovered that none of them were harbouring Salmonella. As other researchers have found that 20% of all dogs have Salmonella in their faeces (okay, okay, poo) we were rather pleased with this result!

Putting the risk in perspective

The risk to humans from harmful bacteria is much exaggerated. That is not to say that bacteria can’t cause health problems in humans or that such health problems can’t be serious, including death. But it is important to put the risk into perspective. Grocery store shopping trolley handles have more germs than public toilets, making them one of the worst public places for germs, according to researchers at the University of Arizona. They found that shopping trolleys were loaded with more saliva, bacteria and even faecal matter than escalators, public telephones, and even public bathrooms.

Why ethically reared meat carries a lower risk

Whether raw meat harbours harmful bacteria is largely determined by how the animal is slaughtered and the way in which the meat is then prepared. Small, ethical producers tend to have much, much higher standards in this regard. Yet another reason why we use certified organic, wild and free range meat at Honey’s. 

What the experts say

“There are endless sources of Salmonella present in the environment, but most do not cause pathogenic contamination, meaning the source can test positive but never cause illness. Pools of standing water, unwashed vegetables, buildings that contain rodent populations, open fields where birds fly overhead, the areas around bird feeders and bird houses, and, yes, bags of commercially produced dry kibble – all are potential sources of contamination. Most commonly, vets don’t even do a diarrhea panel, and simply say: ‘If your dog has acute illness and you feed raw food, the cause is the raw food, probably E.Coli or Salmonella.’ They make huge, sweeping generalisations not based on testing, but based on their personal and incorrect assumptions. Most cases of diarrhea pertaining to raw food are a dietary transition problem, not a pathogenic infection. Even if a veterinarian does do a faecal screening test it has its own limitations. It will simply say it’s positive for Salmonella, but not what subspecies. Most are not pathogenic.” Dr. Karen Becker, veterinary surgeon and author of ‘Dr. Becker’s Real Food for Healthy Dogs and Cats’.

“Thanks to dogs’ industrial-strength digestive systems, their strong stomach acids usually disarm the Salmonella bacteria before they can cause illness. And even if enough of the bacteria survive and manage to take up residence in the dog’s digestive tract, he may well be completely asymptomatic; not all canine carriers of Salmonella become ill. This makes it difficult to know how widespread Salmonella infections are in the canine population. The Merck Veterinary Manual says that ‘many’ dogs are Salmonella carriers, adding that, unlike in humans, ‘clinical disease is uncommon.’” Denise Flaim, ‘Whole Dog Journal’

“The witch hunt for Salmonella is misguided. Yes, Salmonella has the potential to harm humans and some severely immune compromised dogs (although removing beneficial bacteria from their diets may be short sighted). But should raw foods be robbed of their natural nutrition in lieu of washing our hands after serving? The conventional mindset of preventing disease is backwards thinking and initiates a slippery slope of ill health. While dogs and people who eat sterile foods won’t be harmed by acute Salmonella poisoning, they will start to suffer chronic disease from the lack of beneficial bacteria. This deficiency in beneficial bacteria will result in digestive issues and a degradation of the immune system and this will soon be seen as allergies, chronic disease and, ironically, more susceptibility to pathogens such as Salmonella! Maybe Salmonella wouldn’t be as much of a threat to dogs and people in the first place if their intestinal flora wasn’t debilitated by processed foods and the overuse of antibiotics!” Dana Scott, Dog’s Naturally Magazine

A word about green tripe

You may have noticed that Honey’s doesn’t offer green tripe or any recipe containing green tripe. Why not? Although it is terrifically good for dogs (packed with nutrition and beneficial bacteria such as lactobacillus acidophilus) it is not and can never be suitable for human consumption because it may harbour pathogenic bacteria. Washed tripe – which Honey’s does supply – has the bacterial content removed but still provides nutrients. If you do buy green tripe for your dog (or a raw food containing green tripe) we would advise you to store it well away from any food to be consumed by humans and also to observe extremely strict hygiene. Many raw dog food producers imply that their food is suitable for human consumption although they are using green tripe in their recipes.

Honey’s follows a zero tolerance policy

The legislation that exists for raw pet food is stricter than that found on raw meat found in our supermarkets. Raw pet food companies must send their products off to a laboratory for regular testing of Salmonella, and Enterobacteriaceae species such as E.Coli and Yersinia. There is zero tolerance, for example, for Salmonella and if found the entire batch of food needs to be recalled and destroyed.

Another reason to choose Honey’s

By law we are not allowed to say our food is suitable for human consumption… but if we weren’t selling it as dog food, it would be. It is fresh and its British and it comes from certified organic, wild and free range producers. Moreover, our kitchens are kept to the same standard as kitchens used for the preparation of human food. One of the many advantages of using meat that is suitable for human consumption is the fact that it will have a low to non-existent parasite burden.

Top tips for handling raw dog food

  • Wash your hands with hot water and soap before and after handling your pet’s food.
  • Wash and disinfect all surfaces and utensils that have been in contact with raw meat.
  • After each use, wash your pet’s bowls, dishes
    and utensils with soap and hot water, rinse properly and dry before the next use.
  • Dishwash on a high temperature setting.
  • When storing pet food in the fridge ensure raw products are at the bottom. Keep in closed containers.
  • Defrosting raw food in the fridge will limit bacterial growth.
  • Provide separate working areas for preparing your raw food.
  • Do not let food waste build up.

In conclusion

If you raw feed your dog and follow the same hygiene precautions you would use when handling food for human consumption (not just meat but fruit and vegetables, too) the risk of bacterial contamination is minimal. The scientists say so. And so do the millions of raw feeding humans!