The Gut Microbiome and pet health.
The Gut Microbiome and pet health.
What is the microbiome?
Microbiota are the organisms – bacteria, archaea, fungi and viruses that are found within the microbiome.
The microbiome is the above organisms and all the products that they produce.
The things they produce will influence the environment around them as well.
Every surface of the body, has a distinct microbiome – this includes the mouth, nose, GIT, skin etc.
For us, the GIT is the one we are interested in today.
The system is very diverse and complex. The GUT microbiome contains 10 trillion bacteria – most are in the small intestine and colon. These release compounds that then affect the immune system and its function, they also play a role in how the brain matures, the intestinal tract and also have an effect on behaviour.
What influences the Gut Microbiome?
Everything!
This will change over the animals’ lifetimes, however, it is affected by age, sex, sleep, exercise, diet, social members, hygiene and environmental exposure amongst other things.
Some things we can modify, others we can’t.
What does the Gut Microbiome do?
As mentioned before, the microbiome is involved in many things including the maturation of immune system, establishing and maintaining intestinal permeability of the git barrier (every heard of leaky gut?), synthesis of vitamins and extraction of nutrients, maturation and function of microglial cells (cells involved in protecting brain from injury), regulation of myelination of nerves in prefrontal cortex, function and maturation of blood brain barrier, its involved in the hypothalamus-pituitary adrenal axis – (HPA) stress response system, and some microbiota are also responsible for the production of neurotransmitters.
How does the Gut and Brain talk?
A two-way relationship exists between the brain and the digestive tract.
This is known as the gut-brain axis. Information goes both directions with vagal and spinal nerves - neurons that are outside the brain.
There are circulating cytokines (pro and anti-inflammatory) and circulating gut hormones.
Cytokines are proteins that control the grow and activity of other immune systems cells and blood cells. They either fight or promote inflammation. They can travel within the blood stream, or communicate to other nerves within the body.
Hormones are also found in the gut, and these can communicate either by passing through the tight junctions within the intestines or travelling in the blood stream etc. Enteroendocrine cells produce at least 20 different gut hormones.
Microbiota control amino acid availability in the GIT and this can then influence the amount of neurotransmitters that are synthesised within the body. IE if some of the GIT bacteria use tryptophan, then the tryptophan remaining will be less for the body to use to produce serotonin, and vice versa, if the bacteria do something that produces more tryptophan, then the body is able to produce more serotonin for use within the brain.
More about Serotonin.
Having too much serotonin is bad and not having enough is also bad. It needs to be in balance.
Serotonin is a chemical that acts as a neurotransmitter and as a hormone. Serotonin carriers messages between nerve cells in the brain and within the body.
Its important for mood modulation, influences learning and memory, aids in sleep, digestion, wound healing, blood clotting etc
Lack of serotonin is linked with depression and anxiety amongst other conditions.
Serotonin syndrome occurs when the levels of serotonin are too high. This is rare to happen and is usually associated with multiple medication/supplements mixing. Symptoms include increase in heart rate, muscle tremors, restlessness, panting and agitated appearance. The animal may seem disorientated or confused and they can have seizure.
Probiotics and the importance of them
Probiotics have been shown to be beneficial by modulating the microbiome.
Different microorganisms have been shown to have different effects.
Ie Lactobacillus reuteri has been linked with an increase in plasma oxytocin and reduction in pro-inflammatory cytokines, up regulates T cells (immune system cell to help fight infection and inflammation) and also overall reduction in anxiety. While Bifidobacterium longum, has been linked with reduction in anxiety and displays of various behaviours (jumping, barking, spinning, pacing) in situations the dog would usually find stressful.
Prebiotics
These are non-digestible compounds that create changes in the microorganism that have beneficial effects usually by fermentation. They allow for growth of good bacteria, and help the bacteria produce beneficial compounds.
Microbiome and Disease
Some diseases that have been linked to disruption in the microbiome include IBD/IBS, obesity, cancer, inflammation, diabetes, atopy and food intolerances, cognition, depression and anxiety.
What else do we know?
Chronic stress increases intestinal permeability.
Gut microbiota are involved in the production of the proteins that form the junctions to reduce the intestinal permeability.
When there are breaches in the intestinal barrier, we may end up with “leaky gut”, with increased cytokines, systemic infection, and increased inflammation within the body.
Corticotrophin-releasing factor (CRF) is a hormone produced in response to stress. The hypothalamus secretes this hormone to stimulate the hypothalamus pituitary adrenal axis.
An increased HPA aix, results in increased intestinal permeability. This explains stress colitis etc.
How do probiotics and help?
They can reduce or protect against stress. They can help the body to produce the right proteins, to keep tight gut intestinal cell junctions and prevent leaky gut.
They will also help protect against bad bacteria.
The disrupted microbiome has been directly linked with depression and anxiety.
Depressed individuals often have an increased HPA, linking to increased inflammation in the gut etc. Sometimes this is the chicken and the egg scenario too – which one came first.
Humans, dogs, horses and rodents (and assumably other species too), have altered GI flora in the animals that have IBD or IBS. Patients with IBD/IBS also often have depression and or anxiety (chicken or the egg scenario again). They may also have alterations in attention, emotions etc. T
“Probiotics are live bacteria that when fed, have a beneficial effect,”
“They decrease the pH in the gut and that helps the dog’s own good gut bacteria thrive.” Probiotic bacteria can also attach to the intestinal cells and release substances, which helps promote the growth of good bacteria. (Grain Free Dog Food Vs. Regular n.d.)
Probiotics normalize the conditions in the intestines by changing the local acidity of the digestive tract and releasing short-chain fatty acids.
This gives dogs a leg up if they end up ingesting harmful bacteria such as Salmonella. Probiotics help inhibit the growth of these bacteria by competing for the same nutrients and resources. Boosting the populations of helpful bacteria limits the nutrients available for the bad bacteria and reduces their numbers to levels that your dog can tolerate better. (The power of probiotics 2021)
Your dog’s gastrointestinal tract contains about 70% of their immune system, putting it on the front line for preventing pathogens from accessing the rest of the body. By normalizing the conditions in the digestive system, probiotics allow the immune system to function properly. (The power of probiotics 2021)
The Purina Pet Care Center conducted a 15-week blinded, placebo-controlled crossover study, which administered BL999 to 24 Labrador retrievers that exhibited anxious behaviors. Over 90 percent of dogs showed improvement in their anxious behaviors over the course of the study, the release states. (‘New products from Purina and BI target stress in veterinary patients’ 2018)
“In addition, dogs in the study showed reduced salivary cortisol concentration, decreases in heart rate and increases in heart rate variability in response to various stimuli-all of which were considered physiologic evidence of improvement,” Dr. McGowan explained in the release. (‘New products from Purina and BI target stress in veterinary patients’ 2018)
Diet – you are what you eat
Healthy diet containing prebiotics has also been associated with reduced risk of cognitive decline, anxiety and depression.
Poor quality diets in humans (high fat, low fibre) have shown reduced microbial diversity, this includes in offspring from maternal side as well.
Prebiotics are indigestible soluble fibres that ferment in the colon and create short chain fatty acids. These fatty acids can lower inflammation and support gut health.
So what do I recommend?
Adding in probiotics and ensuring an animal has a species appropriate diet that meets his or her individual needs as well is super important. The probiotics I see as something that may aid your animal from the inside out and should cause no harm. However as always, any new behaviours, that are sudden, or out of character for your pet, or behaviours that are worsening and or not responding to changes you make, must be seen by a veterinarian.
We use Pro Plan Calming care which contains Bifidobacterium longum, and ProN8ure which contains a mixed blend including Lactobacillus acidophilus, Lactobacillus delbrueckii subspecies bulgaricus, Lactobacillus plantarum, Lactobacillus rhamnosus; Bifidobacterium bifidum; Enterococcus faecium; Streptococcus salivarius subspecies thermophilus.
One is given in the morning and the other in the evening. These are easily mixed into lick mats etc and the overall benefits I have seen include behaviour and reduction in itching and gastrointestinal upsets.
Reference list
American cancer Society 2019, Cytokines and Their Side Effects, www.cancer.org.
Ann Wortinger 2019, Prebiotics and Probiotics for Dogs and Cats, Today’s Veterinary Nurse.
Cleveland Clinic 2022, Serotonin: What Is It, Function & Levels, Cleveland Clinic.
Foster, JR 2001, ‘The functions of cytokines and their uses in toxicology’, International Journal of Experimental Pathology, vol. 82, no. 3, pp. 171–192.
Grain Free Dog Food Vs. Regular n.d., www.purina.com, viewed 17 March 2023, <https://www.purina.com/articles/dog/nutrition/benefits-of-probiotics-for-dogs>.
Haug, L 2023, ‘The Gut Microbiome and behaviour’, IAABC, viewed 17 March 2023, <https://iaabc.edubrite.com/site/coursePlayer.do?dispatch=show&courseSessionId=8229b49e-a78c-11ec-b5a6-0cc47a352292>.
Mondo, E, Barone, M, Soverini, M, D’Amico, F, Cocchi, M, Petrulli, C, Mattioli, M, Marliani, G, Candela, M & Accorsi, PA 2020, ‘Gut microbiome structure and adrenocortical activity in dogs with aggressive and phobic behavioral disorders’, Heliyon, vol. 6, no. 1, p. e03311.
‘New products from Purina and BI target stress in veterinary patients’ 2018, dvm360, vol. 50, no. 1, viewed 21 March 2023, <https://www.dvm360.com/view/new-products-purina-and-bi-target-stress-veterinary-patients>.
Probiotics alone or combined with prebiotics may help ease depression | BMJ n.d.
Serotonin Syndrome | VCA Animal Hospitals n.d., Vca, viewed 17 March 2023, <https://vcahospitals.com/know-your-pet/serotonin-syndrome#:~:text=Affected%20dogs%20often%20have%20an>.
Stress-Related Behavioral Disorders n.d., www.purinainstitute.com, viewed 17 March 2023, <https://www.purinainstitute.com/centresquare/therapeutic-nutrition/stress-related-behavioral-disorders>.
The power of probiotics 2021, Cornell University College of Veterinary Medicine, viewed 17 March 2023, <https://www.vet.cornell.edu/departments-centers-and-institutes/riney-canine-health-center/health-info/power-probiotics>.
Wallace, CJK & Milev, RV 2021, ‘The Efficacy, Safety, and Tolerability of Probiotics on Depression: Clinical Results From an Open-Label Pilot Study’, Frontiers in Psychiatry, vol. 12.
What is the microbiome?
Microbiota are the organisms – bacteria, archaea, fungi and viruses that are found within the microbiome.
The microbiome is the above organisms and all the products that they produce.
The things they produce will influence the environment around them as well.
Every surface of the body, has a distinct microbiome – this includes the mouth, nose, GIT, skin etc.
For us, the GIT is the one we are interested in today.
The system is very diverse and complex. The GUT microbiome contains 10 trillion bacteria – most are in the small intestine and colon. These release compounds that then affect the immune system and its function, they also play a role in how the brain matures, the intestinal tract and also have an effect on behaviour.
What influences the Gut Microbiome?
Everything!
This will change over the animals’ lifetimes, however, it is affected by age, sex, sleep, exercise, diet, social members, hygiene and environmental exposure amongst other things.
Some things we can modify, others we can’t.
What does the Gut Microbiome do?
As mentioned before, the microbiome is involved in many things including the maturation of immune system, establishing and maintaining intestinal permeability of the git barrier (every heard of leaky gut?), synthesis of vitamins and extraction of nutrients, maturation and function of microglial cells (cells involved in protecting brain from injury), regulation of myelination of nerves in prefrontal cortex, function and maturation of blood brain barrier, its involved in the hypothalamus-pituitary adrenal axis – (HPA) stress response system, and some microbiota are also responsible for the production of neurotransmitters.
How does the Gut and Brain talk?
A two-way relationship exists between the brain and the digestive tract.
This is known as the gut-brain axis. Information goes both directions with vagal and spinal nerves - neurons that are outside the brain.
There are circulating cytokines (pro and anti-inflammatory) and circulating gut hormones.
Cytokines are proteins that control the grow and activity of other immune systems cells and blood cells. They either fight or promote inflammation. They can travel within the blood stream, or communicate to other nerves within the body.
Hormones are also found in the gut, and these can communicate either by passing through the tight junctions within the intestines or travelling in the blood stream etc. Enteroendocrine cells produce at least 20 different gut hormones.
Microbiota control amino acid availability in the GIT and this can then influence the amount of neurotransmitters that are synthesised within the body. IE if some of the GIT bacteria use tryptophan, then the tryptophan remaining will be less for the body to use to produce serotonin, and vice versa, if the bacteria do something that produces more tryptophan, then the body is able to produce more serotonin for use within the brain.
More about Serotonin.
Having too much serotonin is bad and not having enough is also bad. It needs to be in balance.
Serotonin is a chemical that acts as a neurotransmitter and as a hormone. Serotonin carriers messages between nerve cells in the brain and within the body.
Its important for mood modulation, influences learning and memory, aids in sleep, digestion, wound healing, blood clotting etc
Lack of serotonin is linked with depression and anxiety amongst other conditions.
Serotonin syndrome occurs when the levels of serotonin are too high. This is rare to happen and is usually associated with multiple medication/supplements mixing. Symptoms include increase in heart rate, muscle tremors, restlessness, panting and agitated appearance. The animal may seem disorientated or confused and they can have seizure.
Probiotics and the importance of them
Probiotics have been shown to be beneficial by modulating the microbiome.
Different microorganisms have been shown to have different effects.
Ie Lactobacillus reuteri has been linked with an increase in plasma oxytocin and reduction in pro-inflammatory cytokines, up regulates T cells (immune system cell to help fight infection and inflammation) and also overall reduction in anxiety. While Bifidobacterium longum, has been linked with reduction in anxiety and displays of various behaviours (jumping, barking, spinning, pacing) in situations the dog would usually find stressful.
Prebiotics
These are non-digestible compounds that create changes in the microorganism that have beneficial effects usually by fermentation. They allow for growth of good bacteria, and help the bacteria produce beneficial compounds.
Microbiome and Disease
Some diseases that have been linked to disruption in the microbiome include IBD/IBS, obesity, cancer, inflammation, diabetes, atopy and food intolerances, cognition, depression and anxiety.
What else do we know?
Chronic stress increases intestinal permeability.
Gut microbiota are involved in the production of the proteins that form the junctions to reduce the intestinal permeability.
When there are breaches in the intestinal barrier, we may end up with “leaky gut”, with increased cytokines, systemic infection, and increased inflammation within the body.
Corticotrophin-releasing factor (CRF) is a hormone produced in response to stress. The hypothalamus secretes this hormone to stimulate the hypothalamus pituitary adrenal axis.
An increased HPA aix, results in increased intestinal permeability. This explains stress colitis etc.
How do probiotics and help?
They can reduce or protect against stress. They can help the body to produce the right proteins, to keep tight gut intestinal cell junctions and prevent leaky gut.
They will also help protect against bad bacteria.
The disrupted microbiome has been directly linked with depression and anxiety.
Depressed individuals often have an increased HPA, linking to increased inflammation in the gut etc. Sometimes this is the chicken and the egg scenario too – which one came first.
Humans, dogs, horses and rodents (and assumably other species too), have altered GI flora in the animals that have IBD or IBS. Patients with IBD/IBS also often have depression and or anxiety (chicken or the egg scenario again). They may also have alterations in attention, emotions etc. T
“Probiotics are live bacteria that when fed, have a beneficial effect,”
“They decrease the pH in the gut and that helps the dog’s own good gut bacteria thrive.” Probiotic bacteria can also attach to the intestinal cells and release substances, which helps promote the growth of good bacteria. (Grain Free Dog Food Vs. Regular n.d.)
Probiotics normalize the conditions in the intestines by changing the local acidity of the digestive tract and releasing short-chain fatty acids.
This gives dogs a leg up if they end up ingesting harmful bacteria such as Salmonella. Probiotics help inhibit the growth of these bacteria by competing for the same nutrients and resources. Boosting the populations of helpful bacteria limits the nutrients available for the bad bacteria and reduces their numbers to levels that your dog can tolerate better. (The power of probiotics 2021)
Your dog’s gastrointestinal tract contains about 70% of their immune system, putting it on the front line for preventing pathogens from accessing the rest of the body. By normalizing the conditions in the digestive system, probiotics allow the immune system to function properly. (The power of probiotics 2021)
The Purina Pet Care Center conducted a 15-week blinded, placebo-controlled crossover study, which administered BL999 to 24 Labrador retrievers that exhibited anxious behaviors. Over 90 percent of dogs showed improvement in their anxious behaviors over the course of the study, the release states. (‘New products from Purina and BI target stress in veterinary patients’ 2018)
“In addition, dogs in the study showed reduced salivary cortisol concentration, decreases in heart rate and increases in heart rate variability in response to various stimuli-all of which were considered physiologic evidence of improvement,” Dr. McGowan explained in the release. (‘New products from Purina and BI target stress in veterinary patients’ 2018)
Diet – you are what you eat
Healthy diet containing prebiotics has also been associated with reduced risk of cognitive decline, anxiety and depression.
Poor quality diets in humans (high fat, low fibre) have shown reduced microbial diversity, this includes in offspring from maternal side as well.
Prebiotics are indigestible soluble fibres that ferment in the colon and create short chain fatty acids. These fatty acids can lower inflammation and support gut health.
So what do I recommend?
Adding in probiotics and ensuring an animal has a species appropriate diet that meets his or her individual needs as well is super important. The probiotics I see as something that may aid your animal from the inside out and should cause no harm. However as always, any new behaviours, that are sudden, or out of character for your pet, or behaviours that are worsening and or not responding to changes you make, must be seen by a veterinarian.
We use Pro Plan Calming care which contains Bifidobacterium longum, and ProN8ure which contains a mixed blend including Lactobacillus acidophilus, Lactobacillus delbrueckii subspecies bulgaricus, Lactobacillus plantarum, Lactobacillus rhamnosus; Bifidobacterium bifidum; Enterococcus faecium; Streptococcus salivarius subspecies thermophilus.
One is given in the morning and the other in the evening. These are easily mixed into lick mats etc and the overall benefits I have seen include behaviour and reduction in itching and gastrointestinal upsets.
Reference list
American cancer Society 2019, Cytokines and Their Side Effects, www.cancer.org.
Ann Wortinger 2019, Prebiotics and Probiotics for Dogs and Cats, Today’s Veterinary Nurse.
Cleveland Clinic 2022, Serotonin: What Is It, Function & Levels, Cleveland Clinic.
Foster, JR 2001, ‘The functions of cytokines and their uses in toxicology’, International Journal of Experimental Pathology, vol. 82, no. 3, pp. 171–192.
Grain Free Dog Food Vs. Regular n.d., www.purina.com, viewed 17 March 2023, <https://www.purina.com/articles/dog/nutrition/benefits-of-probiotics-for-dogs>.
Haug, L 2023, ‘The Gut Microbiome and behaviour’, IAABC, viewed 17 March 2023, <https://iaabc.edubrite.com/site/coursePlayer.do?dispatch=show&courseSessionId=8229b49e-a78c-11ec-b5a6-0cc47a352292>.
Mondo, E, Barone, M, Soverini, M, D’Amico, F, Cocchi, M, Petrulli, C, Mattioli, M, Marliani, G, Candela, M & Accorsi, PA 2020, ‘Gut microbiome structure and adrenocortical activity in dogs with aggressive and phobic behavioral disorders’, Heliyon, vol. 6, no. 1, p. e03311.
‘New products from Purina and BI target stress in veterinary patients’ 2018, dvm360, vol. 50, no. 1, viewed 21 March 2023, <https://www.dvm360.com/view/new-products-purina-and-bi-target-stress-veterinary-patients>.
Probiotics alone or combined with prebiotics may help ease depression | BMJ n.d.
Serotonin Syndrome | VCA Animal Hospitals n.d., Vca, viewed 17 March 2023, <https://vcahospitals.com/know-your-pet/serotonin-syndrome#:~:text=Affected%20dogs%20often%20have%20an>.
Stress-Related Behavioral Disorders n.d., www.purinainstitute.com, viewed 17 March 2023, <https://www.purinainstitute.com/centresquare/therapeutic-nutrition/stress-related-behavioral-disorders>.
The power of probiotics 2021, Cornell University College of Veterinary Medicine, viewed 17 March 2023, <https://www.vet.cornell.edu/departments-centers-and-institutes/riney-canine-health-center/health-info/power-probiotics>.
Wallace, CJK & Milev, RV 2021, ‘The Efficacy, Safety, and Tolerability of Probiotics on Depression: Clinical Results From an Open-Label Pilot Study’, Frontiers in Psychiatry, vol. 12.