Canine Probiotics, What We Do and Don’t Know, Study Participants Needed…
Hippocrates, a Greek physician of the Age of Pericles, considered the founding father of modern medicine and the reason doctors take the Hippocratic oath in college, said all disease begins in the gut, that we were to let food be our medicine. We’re only now really coming back around to that simple statement. The amazing vitamins, minerals and phytochemicals in food aside, what Hippocrates could not have known was the crucial role that life living inside our gut tract played in the process. Termed the gut flora, we now know that these little guys play a pivotal role in our physical and mental well being, that keeping them happy is of the utmost importance. It’s undoubtedly the same for dogs but after that things get a little grey. So here’s everything we know about canine probiotics, beginning, as I so often do, with what we know of the gut flora in humans.
What is the Gut Flora and What Does it do for us?
Your gut is full of life. It houses trillions of little bacteria, viruses, fungi and a whole myriad of other microscopic living organisms. Individually these guys are called microbes but collectively they are known as the gut microflora (or microbiome). While small, there are so many of them that, collectively they can make up 1-2kg of your body weight. Needless to say, it’s no accident they’re there.
There are roughly 40 trillion bacterial cells in your body and only 30 trillion human cells. That means you are more bacteria than human
In omnivores and herbivores, most of our gut flora are found in a small “pocket” of our large intestine called the caecum. Think of the caecum as a rich garden, a garden that if we fertilise and water correctly and don’t spray it with too much nasty stuff, will bestow on us wonderful, vital, life-affirming food items which we can use to sustain ourselves. It works as a symbiotic relationship, meaning both organisms benefit. We give them a safe place to live, food and shelter. They digest the things we can’t (largely plant fibre and undigested protein) and turn these into items we badly need, such as short-chain fatty acids, vitamins and minerals, all of which we can then absorb. In fact, studies show fibre alone may help prevent a myriad of diseases from weight gain and diabetes to heart disease and the risk of cancer. None of that would be possible without our microbe friends.
When the microbiome from an obese twin mouse was transferred to regular mice, they gained more weight than those that had received the microbiome of the lean twin, despite both groups eating the same diet
Your gut flora can do a lot of other things too. Their mere presence works to keep the numbers of bad bacteria, yeast and sometimes parasites in check. They form an integral part of the intestinal barrier, protecting the host from pathogen entry via a process called colonisation resistance. They can interfere with the adherence of pathogens to the intestinal mucosa by induction of mucus production. Furthermore, their byproducts reduce the growth of potential pathogens.
They also function in repair. Those found in yoghurt, largely Bifidobacteria and Lactobacilli species, can help seal gaps between intestinal cells and prevent leaky gut syndrome which in turn will reduce susceptibility to food allergies (something so many dog owners jump to raw dog food to fix food intolerances and leaky gut, so listen up!). They even clean the place up a bit, eating not only undigested food but also sloughed epithelial cells and mucous.
All absolutely fascinating. But it goes even deeper than that…
Meet the Enteric Nervous System, the vital organ you never knew you had…
Only recently we have learned that the gut microbiome, their metabolites and components strongly influence our immune systems. They are necessary not only for immune homeostasis (stability), but by communicating with immune cells they also influence your susceptibility to many immune-mediated diseases and disorders. The gut microbiome can control how your body responds to infection and almost certainly play a role in intestinal diseases such as irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD).
How do they do this? It’s all thanks to a recently discovered organ (it had been hiding out between the layers of the gut) termed the Enteric Nervous System or ENS, for short. It turns out we have two nervous systems – the central nervous system (made up of the brain and the spinal cord), and the ENS (linked to our gastrointestinal tract). Both systems are linked through the vagus nerve, which runs from the brain-stem to the abdomen. Also called the “second brain” due to the number of neurons and signals it transmits (more than the brain, in fact), the ENS controls digestion, swallowing and the release of enzymes that break down food and the control of blood flow, nutrient absorption and elimination. While perhaps not capable of actual thought, not that we yet know of anyway, it can certainly affect how you think. With communications to our Central Nervous System (CNS), the ENS is now thought to be responsible for a lot of your mood. In fact, approximately 80-90% of your serotonin (the happy chemical) comes from in and around the gut. It’s thought the emotional shifts associated with hunger and satiety but also gut upset, such as IBS, constipation, diarrhoea, bloating and pain, are all controlled by the ENS. But the ENS is not alive. It can only react to certain cues from the gut. And guess who’s responsible for those cues?! You guessed it, your microflora. Scientists now know that the ENS senses and reacts to the dynamic ecosystem of your gastrointestinal tract, translating chemical cues from the gut environment into neuronal impulses that are passed on to the CNS to make it take action.
The connection between gut health and mood has been known for some time, as individuals suffering from bowel-disorders such as Celiac disease, irritable bowel syndrome, or leaky gut are more likely than others to also suffer from autoimmune diseases and mental issues such as depression and anxiety.
Keep Them Happy, You Will be Happy but Treat Them Badly…
So, a healthy gut flora has the capability of affecting your body’s vitamin and mineral absorbency, hormone regulation, digestion, vitamin production, immune response and ability to eliminate toxins. Studies show it can positively affect weight control, your susceptibility to disease and your overall mental health. When your gut flora is happy and in harmony, you can expect all these things in abundance. It follows, however, that when they are not happy, or in dysbiosis (an imbalance between beneficial and harmful bacteria), you can expect the opposite. Here’s how to keep them happy:
Eat More Probiotics. Of all the microbes that live inside you, bacteria are the most studied. When people speak of “probiotics” (from the Latin, meaning for-life), they are largely talking about bacteria alone. In this way, probiotics generally consist of live bacteria. Some of the most popular sources of “good bacteria” for human guts include yogurt (whole, unpasteurised, probiotic yoghurt is one of the best sources of probiotics), kefir (a fermented probiotic milk drink) or any fermented vegetables (including sauerkraut (cabbage), kimchi (a fermented mix of veg, Korean style), miso (fermented soybeans), kombucha (fermented tea), pickles etc).
Cheat and take a Probiotic Supplement. Most of us Westerners are clearly undereating in the above and not making our own pickled veg so feel free to cheat with a probiotic such as Udos, which is one of the top rated probiotics on Amazon.
Eat More Prebiotics. Prebiotics (from the Latin, before–life) are essentially microbe food. You need to eat more fibre for starters, including fresh, raw vegetables and fruit. There are “super prebiotics” out there which is like catnip for them, including acacia gum, raw chicory root, artichoke, raw dandelion green, any of the coarser green leafy veg, raw garlic and raw asparagus. Get them in when you can. It’s best to feed prebiotics on their own on an empty stomach, for maximum effect, that way they pass through the digestive juices. They’re not completely ruined with a meal, just less effective, and never take them after. Best first thing in the morning (at least 30mins before brekkie) or before bed.
Ease off antibiotics. Antibiotics destroy life. That’s their job. When you take them (likely for a very good reason though it is a worry there are ads on the radio telling us not to take antibiotics for a common cold, as if we bought them in newsagents) you are altering your gut flora. Bad bacteria can then move into the newly created space. Over time (days to weeks) your gut flora can rebound (should you take all the right steps) but studies show even if you do (most of us don’t) those surviving bacteria have decreased ability to produce proteins, absorb iron, digest certain foods and produce essential chemical molecules.
Ease off food containing anti-life. All processed food contains anti-life. It’s why your packaged fruit and vegetables do not go off. Anything in a packet has been preserved so it can stay on shelves longer. If you eat this, anti-life will wash over your delicate gut flora and harm it.
Remove chlorine from your water. Chlorine kills life hence we fill swimming pools with it. But it also decimates our gut flora when consumed which greatly weakens us. Ever notice that you always get a cold after a dip in the local pool? The most chlorinated environment in the world, it’s not because colds like to live there, it’s because you swallowed a mouthful or two of anti-life and with your gut flora in dysbiosis, problems ensue. There are a number of things you can do to avoid chlorine in your water. I had a water filter installed under my kitchen counter. Called a reverse osmosis system, it cost around €180 (£160/$200) and I have to change the filter once a year. It removes all impurities such as particulates and bacteria etc but also chlorine and a few other bits. The water tastes amazing without all that crap in it BUT it does mean when you drink tap water from anywhere else it tastes gross, which has ruined many a dinner for me!
If I had my chance again, I probably would have gone up a level and picked something that removes the flouride too. Flouride was added to our water supply around the same time they were adding lead to our pipes, lead to our gasoline and DDT to our lakes. The rest have been removed but chlorine remains in some countries (just not the forward-thinking like Denmark and Luxembourg who banned it). For this you need something like the iSpring RCC7AK (Amazon). It’s a beast. It does everything but also removes lead, hormones and yes, flouride. It also alkalises and remineralises your water with ionized minerals including calcium, magnesium, sodium, and potassium.
You can save a few pennies and hassle by avoiding the under counter water filter systems and simply pick up some charcoal sticks. Left in a simple filter water jug, charcoal is great at removing chlorine from the water. They last for around six months and you can fertilise your plants with them afterwards!
GUT FLORA TERMINOLOGY RECAP
PROBIOTICS – The microbes, the live organisms
PREBIOTICS – Microbe food
SYNBIOTICS – Pro and prebiotics working together
You are now beginning to learn just how important probiotics and a happy gut flora are to the health and well being of a human. You won’t be surprised to learn that it is very much the case for all other complex animals thus far studies including horses, cattle, monkeys, rodents, fish, insects, everyone is working with them. So let’s take a look at the average dog, what constitutes good canine probiotics and see how the average dog is scoring on the “happy gut scale”.
Asides eating the odd stool, the average dry-fed dog receives nothing by way of suitable probiotics. Ever. Our vets believe it is right and proper that for their whole life dog’s should eat old, inert, nutrient defunct food made by candy manufacturers. Moreover, these processed diets contain copious amounts of anti-life. That year-old kibble is so preserved it can sit in a warm, open, sweaty, paper bag for weeks and not even mould will grow on it. Even their treats, from dental chews to pigs ears, the latter being pieces of meat which can sit in warm, perspex boxes for months in a pet shop without going instantly rotten (they do, you just don’t know it). Food aside, your dog lives on the floor. They sniff and lick antibacterial floor chemicals daily. Then, when such a way of life resulting in them presenting with a gut upset (the number one reason for visiting the vet after recurring skin issues) they ALWAYS get antibiotics, often coupled with a steroid / NSAID / antispasmodic for that IBS-type issue, to alleviate the visible symptoms. Which they do, albeit temporarily, and all the while the problems keep going in, unnoticed. As the diet is never addressed in any real way, unfortunately, that dog will be back for more and more antibiotics and they will consume nothing to resolve the microflora dysbiosis in the gut.
Compare this to raw fed dogs that eat alive food, usually off the ground, incorporating lots of soil bacteria. Contrary to popular mythology, this fresh food is no more dangerous for pets than it is for us. As with all food, it contains bacteria, many good, some bad. More importantly, fresh, biologically appropriate food (raw meat and bone) contains all the bits (prebiotics) their gut bacteria need to thrive. As with humans eating raw or pickled veg or fermented dairy products, we can expect dogs eating this natural diet to have a more stable gut flora.
Is it not reasonable to assume that dogs, certainly the dry-fed variety, suffering diseases such as increased infection, leaky gut, weight gain, diabetes, heart disease, cancer, poor mood, might have gut flora dysbiosis? Studies show that for gut issues this is certainly the case. As with humans, bacterial dysbiosis is common to various gastrointestinal disorders of dogs. Even without a change in diet probiotics benefit dry-fed dogs suffering from Irritable Bowel Disease and diarrhoea (Suchodolski et al. 2012, Minamoto et al. 2016, White et al. 2017). In fact, microbiota dysbiosis is now shown to be at play in exocrine pancreatic insufficiency too.
It follows that the majority of at least dry-fed dogs need suitable pre and probiotics ASAP (though a better diet should probably be your first port of call – you can’t build a strong house on crappy foundations). So let’s learn up on what might constitute ideal canine probiotics.
The canine gut flora is not the same as ours…
Humans are, to all extents and purposes, practically herbivorous with maybe a little meat thrown in there. Our gut and gut flora is thus adapted for a plant diet. Our systems are less acidic, which they like, and when we feed them plant fibre (complex carbohydrates) they thrive.
Dogs, on the other hand, eat a meat-based diet, that is, a diet far, far lower in carbohydrates of any kind.
Carnivores such as wolves rarely eat the stomach contents of their prey, that’s why you have never seen a video of them eating the insides of the belly. Studies show that dingos too, which were wild domestic dogs 2,000-4,000 years ago, avoid the stomach contents of all but their smallest prey.
They have a very rapid, very acidic gastro-intestinal system (something many of our gut microbes would not like). When the dog is digesting food, their gut acids can plummet to pH1.5. This is ten times lower than pH2.5 and 100 times lower than pH3.5 (where we are, give or take). There are many reasons for this battery-acid environment. First, they consume whole animals. They need to properly process meat and bone, teeth and hair. Not an easy meal. Secondly, they are scavenging carnivores, specialists at finding carcass (vultures won’t live near packs of dogs, they outcompete them to their main food source). This meat will be crawling with baddies and yet the dog eats it (as he does a meaty bone in the garden) to no ill effect. Salmonella and E.coli struggle to get through this acid chyme. Also, dogs have no caecum (the little pocket in your large intestine where we house most of our gut flora). As such, they have far less (in numbers) bacteria in their colon than humans, although studies show they still have a very diverse flora. Finally, dogs clearly react differently to some microbes than we do. For example, known human pathogens such as Clostridium spp, E.coli and Salmonella spp are housed by normal, healthy dogs, symptom-free (though some scientists seem to want to make a song and dance about this in raw fed dogs).
When we know that physiological changes in the gut tract, including the acidic nature of the stomach, and the bile salts and enzymes present in the small intestine, have an effect on both the species of microbiota that will inhabit each region and their concentrations present, and that authors have previously shown the dog is host to very limited number of gut microflora (Kearns et al. 1998), should we not expect that their pre and probiotics would differ to some degree from ours? Swanson et al. (2011) looked at this using dogs, humans and mice and found the primary functional categories of microbes in each animal were similar, with those for carbohydrates making up 12.5–13.0% of sequences and those for protein metabolism making up 8.1–9.1% in the dog.
However, a crucial point here is that this is the microbiota of client and laboratory dogs, the vast majority of whom were fed a dry, cereal-based diet. These diets comprise largely of cereal (carbohydrate) filler and low protein, only a small part of which could be considered “meat” (more on the meat meal used in pet food here), the rest being made up with cheap plant protein additions. It follows that cereal-based pet food is very largely plant food and we would expect the microbiota to reflect that to some degree.
This begs the question, is there differences between dry and raw fed dogs?
Dry versus Raw-Fed Canine Gut Flora…
All mammalian intestinal tracts are made up of three distinct sections, the duodenum, small intestine (or jejunum) and large intestine/colon (ileum), and each house a different microbial community. In the dry-fed dog, it is generally accepted that the duodenum of healthy dogs consists largely of six primary phyla: Firmicutes (46.4%), Proteobacteria (26.6%), Bacteroidetes (11.2%), Spirochaetes (10.3%), Fusobacteria (3.6%), and Actinobacteria (1.0%) (Xenoulis et al., 2008). The predominant bacterial phyla of the small intestine was Proteobacteria (46.7%), Firmicutes (15.0%), Actinobacteria (11.2%), Spirochaetes (14.2%), Bacteroidetes (6.2%), and Fusobacteria (5.4%) (Suchodolski et al. 2009). While the large intestines were dominated with the orders Fusobacteriales (30%), Clostridiales (25%), Bacteroidales (22%), and Enterobacteriales (20%) (Suchodolski et al. 2008).
Again, this cannot yet be held up as a normal profile for a raw fed dog fed a biologically appropriate diet, at least until more is known. Algya et al. (2018) compared the microbiota of dogs fed dry, cereal-based extruded kibble and dogs fed biologically appropriate raw dog food and found raw fed dogs had significantly less Actinobacteria and Firmicutes and significantly more Fusobacteria, Proteobacteria and Bacteroidetes than dogs fed the kibble.
It seems it’s the very same in raw versus dry-fed cats. As with the dog, the major bacterial groups in dry-fed cats are similar to those found in other mammals, with Firmicutes, Bacteroidetes, Actinobacteria and Proteobacteria constituting more than 99% of intestinal microbiota. Kerr et al. (2014) investigated the faecal microbiota of domestic cats fed raw whole chicks versus an extruded cereal-with-chicken kibble diet. They found the raw-fed cats had greater proportions of Lachnospiraceae (15 v. 5 %), Peptococcus (9 v. 3 %) and Pseudobutyrivibrio (4 v. 1 %) and smaller proportions Faecalibacterium (0.2 v. 1%) and Succinivibrio (0.1 v. 1.2%) than dry fed cats, respectively. Furthermore, and crucially, Lactobacillus and Bifidobacterium (they’re the fella’s we get from probiotic dairy, like yoghurt and dairy) were present in the majority of samples from cats fed kibble but were not detected in the samples for raw-fed cats. Also, as in dogs and humans, studies suggest a dysbiosis is at play in feline inflammatory bowel disease (IBD).
These shifts in faecal bacterial populations compared with feeding a whole-prey diet may impact the functional capacities of the microbiota and its interaction with the host. Further research is warranted to determine the impacts of these shifts on long-term health of domestic cats.
So, are human pre and probiotics good for dogs?
Our natural inclination is to look at what we are doing successfully in human nutrition and try apply it in dogs and when it comes to food, this isn’t so bad an idea. Studies show dogs react in the same way as humans to a variety of food and chemical substances, it’s why we test everything on them. So don’t be like the vet who cynically won’t even try fresh food, give it a quick google and try it out, see what happens! You’ll see a difference or you won’t (or you’ll see some runny poo!). These days it seems everyone is giving their dogs all sorts of pre and probiotics meant for humans, such as yoghurt and kefir. Supporters testify that they are having a positive effect. I don’t doubt this and the data verifies it.
In terms of modulating the canine GI microbiota, complex carbohydrates and dietary fibre-based prebiotics (in other words, plant-based prebiotics) have been the major nutritional strategies studied thus far. Fructans, including chicory root extract, inulin, oligofructose, and short-chain fructooligosaccharides (scFOS) have been studied in greater detail in dogs than other ingredients with prebiotic potential. Both chicory and beet pulp have been found to alter the dog’s gut bacteria increasing faecal bifidobacteria and lowering faecal clostridia. did the same. Similarly, Gagné et al. 2013 successfully used a synbiotic to improve the bacterial flora of the colon and thus better control diarrhoea in their sled dogs. For those interested, the synbiotic contained Enterococcus faecium, Bacillus coagulans, Lactobacillus acidophilus, fructooligosaccharides, mannanoligosaccharides, Vitamin B1, Vitamin B2, Vitamin B3, Vitamin B6, brewer’s yeast, soy lecithin, magnesium stearate, microcrystalline cellulose, mono-and diglyceraldehyde, and silica dioxide. Further, when Apanavicius et al. (2007) deliberately infected 12wk old pups fed prebiotics (namely 1% scFOS and 1% inulin) they found those receiving the prebiotics suffered less enterocyte (cells of the gut wall) sloughing, had higher total Short Chain Fatty Acid (SCFA) concentrations and a greater faecal content of Lactobacilli. All good news there too.
So human-type pre and probiotics seem to be well worth a go. But authors note there are too few clinical experiments performed to actually test the ability of dietary fibre and prebiotics to promote gut and overall health in dogs (Hooda et al. 2012) only an array of gut health indicators have been assessed, including faecal scores, pH, microbiota, and fermentation end-products. In other words, we’re still not quite sure what the long-term health benefits of these pre and probiotics might be. A recent study of fruit flies pushed this conundrum further. A recent study of fruit flies reveals that gut microbes can influence what we feel we need to eat. They found that when fruit flies were purposefully left short on some dietary amino acids they will naturally crave certain foods to top those levels up, as you would expect. But, when these protein-hungry flies are given more gut microbes of two certain types, the microbes can actually switch off this craving in the fly and direct the animal towards more sugar, which they need, effectively demonstrating a bottom-up pathway of communication of nutritional needs for the first time.
These two bacteria also restored the flies’ reproductive abilities, indicating their bodies were now carrying out normal functions that typically get restricted when there is a nutritional deficiency.
It follows that inoculating your dog with certain bacteria via probiotics of a certain type could possibly lead to the animal selecting foods that suit that sort of bacteria. Of course, this would only apply in dogs permitted to feed in a selective manner but when hungry microbes can dictate pathways such as reproductive abilities in the fly, what else might they be able to do and will it positive or negative the animal? We have no idea.
As we know. raw-fed dogs display a different microbial profile to omnivorous humans and dry-fed dogs, there is great scope here to investigate more carnivore-friendly prebiotics, whatever they may be and Kumar et al. (2017) are the first to have looked into this in greater detail. They divided Labradors into three groups. One was fed a basal diet without probiotic (control), the second, a diet with added probiotic of canine origin (Lactobacillus johnsonii) and the third received a diet containing a probiotic of dairy origin (Lactobacillus acidophilus). Overall, they found that the canine-origin probiotic was superior when compared with the dairy-origin probiotic. The reason for this, perhaps unsurprisingly, is that dogs are not plant eaters. Their gut flora is different. This implies that the best canine probiotics should be canine-focused.
It seems, at a very broad, top level, the microbiota of our guts appear quite similar. It is when you dig down into each group, into the thousands and thousands of different families, genus and species, that we see major differences, from one type of mammal to another and even one individual to the next. Our gut microbiota is possibly as unique as our DNA.
Have a dog Suffering Mysterious Gut Upset? I Strongly Recommend a Good Quality Probiotic ASAP…
Thus, if you have a dog with recurring gut issues, pancreatic inflammation, one recovering from antibiotics (studies show following short-term antibiotic administration bacterial taxa may remain depressed for several months in dogs) or simply a dog living on inert, chemically preserved food, you should think about a good dose of probiotics. They can only help. You have three options at this point:
As the studies above show, complex carbohydrate-type prebiotics normally used in humans also have a positive effect in dogs, you could try add in a few of these to your dog (outside of his meal). The most popular here are raw broccoli, chicory or coarse leafy green mixed into a bowl of kefir (or probiotic yoghurt). This might well do the job and certainly worth a go. They’ll love it anyway. I’d pop in a cod liver oil tablet too.
The next level up would be the best over-the-counter canine probiotics you can find. These Here are some on Amazon.
But you can do even better than this, should you reside in Ireland or the U.K.. As no one dog has the same microbiology profile (Davis et al. 1977 found that housed dogs fed the same food for years have marked differences in their microflora) the latest offering from Irish Equine Centre is particularly fascinating. While obviously specialising in horses, the multi-award winning ECI laboratory is the undisputed kings of probiotic therapy. You send in a sample of your dog’s stool, they analyse it and find out what exactly your dog is high or low in. Then they formulate a probiotic unique to your dog FROM THEIR OWN MICROBIOTA. This is called autogenous therapy. They then send you out the probiotic AND cryogenically store your dog’s healthy microbes so should you need more they post them out to you! All for the small sum of €170. For just another €25 you can send in a poo sample a month later to check and see their new profiles. The feedback on this therapy for horses and dogs is simply incredible. If you have a trouble case, I very highly recommend it.
|Level 1||A fresh, biologically appropriate raw diet (BARD)|
|Level 2||BARD with human pre and probiotic foods|
|Level 3||BARD with over-the-counter, canine probiotics|
|Level 4||BARD with over-the-counter, encapsulated canine probiotics|
|Level 5||BARD with autogenous probiotics|
Want to Learn More About Your own gut Flora?
A fascinating book on the whole gut flora subject is Dr David Perlmutter’s “Brain Maker: The Power of Gut Microbes To Heal and Protect Your Brain – For Life”. It’s fascinating. I very highly recommend picking it up.
I have spent a lot of time building up my knowledge. From a doctorate in animal behaviour and nutrition to years in guide dogs and the last seven year inside and out of the pet food industry, I have always provided all my information free to the public, articles that I spend a lot of time putting together. While it’s clearly a passion of mine the fact remains, I can’t do this and a steady job at the same time. Without a salary or fancy sponsorship, I am left trying to monetise my site as much as I can without pushing on you horrible adverts for car loans and crap pet products. One way I do this is by tracking some of the links to products I recommend (as an Amazon Associate I then earn from qualifying those purchases). Another is by popping an ad or two for my own unique supplements in there. Finally, I’m now going to put a donation button at the bottom of my longer articles. So, if this helped you in any way and you feel you’d like to give me the price of a cup of coffee (€3), please free to do exactly that. If you’re strapped and can’t afford it, I can totally sympathise, you’re free to read on, no questions asked. We’re glad to have you on board spreading the word regardless.
Many thanks and continued good health to you and your pets.