Your Dog’s Gut Bacteria and Stress: How are They Related?

Dogs get stressed out just like us. And just like us, many display digestive issues when anxious. For example, how many times have you heard a dog owner or boarding facility owner say a dog had diarrhea the whole time it was there? Their food didn’t change, but their routine and environment certainly did. Some dogs may throw up or drool when stressed as well, all signs that their stomach is upset. Stress also causes behavioral changes in canines, including barking, growling and biting, so understanding how to reduce or alleviate stress is important.

So what does gut bacteria have to do with all this?

There are two basic categories of bacteria that live in the digestive system – good bacteria and bad bacteria. Called the gut microbiome, because the digestive tract is made of up hundreds of different types of bacteria and other microbes, this system needs to be in balance in order for your dog’s body to function properly.

The good bacteria, also called beneficial bacteria, such as probiotics, help keep toxins out of the bloodstream, block bad bacteria, and aid in digestion, immune system function and absorption of nutrients. It’s easy to see why your dog’s stomach may be upset if he doesn’t have enough good bacteria or has too much harmful bacteria in his digestive tract. But what does that have to do with stress?

The Gut-Brain Axis

The brain of many animals (including humans and canines) is connected to the digestive tract in a two-way communication structure. It is this structure that allows the stress we feel in our brain, to affect our gut. Conversely, it also means that what is going in our gut can affect our brain. Including relieving stress.

There have been several studies done on dogs’ gut-stress relationship, and every single one of them found that dogs on probiotics showed less signs of stress than those not on them. One study tested dogs in a boarding environment being fed the exact same diet, the only difference was the probiotics. Another study took already anxious dogs and found that those given the probiotics appeared 90 percent less anxious than those that were not given any. This included reduced instances of spinning, barking and pacing as well as improved heart rate (83 percent of subjects) and cortisol levels (75 percent of subjects).

Part of the reason scientists say this happens is because probiotics produce neurotransmitters like serotonin and GABA, which make us feel good. And as mentioned in the study above, probiotics help lower cortisol, which is known as the stress hormone.

So, if you have a dog that seems constantly stressed, you may be able to help your four-legged friend be more at easy by upping his probiotic intake. It’s a great thing to do in conjunction with training. And, since probiotics also aid in digestion and your dog’s immune system (70 percent of which is housed within the digestive tract), it will also help your dog stay healthier.

If you do choose to go down this path, I use human grade probiotics for my dogs. If your dogs are small get the child probiotics and depending on your dog’s size use accordingly. If you have a dog over 40kg you can get the adult probiotics. I go for the probiotics with more than 10 species of good bacteria or more. Reason being, the more diverse the microbiome the healthier it is.

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  1. Very interesting reading , as much as I am very impressed with the advertising and ingredients and health benifets of your Stay Loyal brand unfortunately we are unable to afford the cost, although I fully agree that it is well worth every cent

    1. it may not end up being that expensive. I find it runs out cheaper than other quality brands around because I don’t hav3 to feed my dog as much, I feed her a lot less than guided

      1. Hi Cheryl, thanks for this post. i feed much less than recommended too and my dogs are in great condition.

  2. I tried to fill in my details on the pist about how to treay your do if it has dry itchy skin but it wouldnt allowe to put my email or dog’s nreed. Help!

  3. Hi Robert, Can you advise which probiotics you give to your dog? I have always fed a heaped teaspoon of Jalna natural yoghurt to my 8kg Boston Terrier and she loves it. I also found it helps with her gas! No where near as stinky! Thanks, Nikki

    1. Hi Nikki, i’m currently using Broad spectrum from Lifespace. There are many that are similar to these.

      1. Lifespace Probiotics are excellent & I take one every morning….How much would you give a 16kg Staffy & do you open the capsule & mix in with her dinner?

        1. Hi Denise, you can give it on the food or as the capsule. Id say 1/4 a cap would be a similar dose as one cap for you.

  4. Hi Robert,
    Thanks for such an interesting post
    Which probiotics are better one from the fridge or one kept at room temp

    1. Probiotics that are kept in the fridge are best, also probiotics are best given when gut is empty not with food as stomach acids are higher, I give Patch Yakult probiotic drink you buy from Supermarket he gets 1/2 the Yakult I drink the other 1/2 around 11am daily.
      He loves it.

  5. Hi boys, another brilliant article. Will be popping down to the chemist for some children probiotics. Had no idea.

    Thank you,
    Rosemary Wright

  6. I have a cavalier who ends up with bloody blood in diarrhoea when ever something is different in her world. Using a dog probiotic from overseas at present has helped the number of times these attacks happen and she seems a lot calmer all the time. Thanks for your artical

  7. I have a question, will probiotics help my miniature pincher who suffers from too much acid, daily he throws up (heartburn) or should be on something like nexium or Rennie.

    1. I would advise against using Nexium over a long period. Not good for humans so probably not good for dogs.

  8. Very informative. Sadly her tummy can’t seem to tolerate plain Greek yoghurt (throws up almost immediately). Some probiotics could be the magic bullet

  9. Hi Robert,
    My Misty is 8.8kg (West Highland Cross). I have just bought Ethical Nutrients Kids Probiotics. It’s in powder form. How much should I give her? I have also started giving her plain yoghurt for the past two days on the advisement of vet because Misty has a sensitive stomach and throws up every so often. Can she have yoghurt and probiotics at the same time? Thanks.

    1. Hi Linda, it should be ok to give both. just one of the kids probiotics should do the trick. Also with dogs that have stomach troubles, don’t underestimate the power of a fast day once a week and also fasting if the stomach is upset. Also feeding less can help a lot with stomach issues.

  10. Thanks for very interesting information, I look after my own microbiome but never thought about Banjo ( Australian terrier) and his. Makes sense thanks again

  11. Can anyone tell me the specific type or name of the grass that dogs eat, as my dog is constantly looking for it around our yard but never seems to find any….If I knew what it was, I would plant a small patch for her…..Thanks.

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