Let's Talk About Probiotics

Television advertising seems saturated with the promotion of products containing probiotics and, more recently, prebiotics. We are now seeing addition of both probiotics and prebiotics to pet foods.

​This article will give you an understanding of the role that probiotics and prebiotics can play in the promotion of gastrointestinal health in dogs. ​

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The intestinal tract, especially the large intestine or colon, is teeming with bacteria. It has been estimated that up to 10% of fecal mass is bacteria. Some of the bacteria are helpful, and some are harmful. In a healthy digestive tract, the ratio of “good” bacteria to “bad” bacteria is in balance. Any disruption in this proportion of good bacteria to bad bacteria can lead to symptoms of poor digestive tract health such as diarrhea, vomiting, abdominal pain, and gas. Antibiotics can be very effective at reducing the number of bad bacteria in the gut, but antibiotics do not discriminate between good and bad bacteria. Consequently, use of antibiotics results in a large kill-off of good bacteria, which itself can cause diarrhea. 

Probiotics are living bacteria that benefit the host when ingested. Prebiotics are nondigestible food ingredients that benefit the host by selectively promoting the growth of the good bacteria without promoting the growth of bad bacteria. Think of prebiotics as “food” for the good bacteria. When used together, the result is a thriving population of good bacteria in the gut and a suppressed population of bad bacteria. 

Certain types of fibre can make very good prebiotics. We can’t digest these fibres, but the good bacteria can. When the fibre (or prebiotic) reaches the colon, the good bacteria changes it through a biochemical process called fermentation, thereby producing byproducts called short-chain fatty acids (SCFAs). SCFAs are very helpful little structures. Not only do they act as an energy source for intestinal cells, but they also maintain a healthy intestinal motility, prevent overgrowth of harmful bacteria, and alleviate intestinal inflammation. Essentially, fibre provides energy for good bacteria, and in exchange, the good bacteria break the fibre down into products that improve colon health. 

Recent studies have shown that feeding probiotics to dogs improves stool quality. ​

Feeding probiotics to dogs before, during, and after a mildly stressful event (such as traveling) can reduce the likelihood that the dog will experience diarrhea from the stress. Additionally, some studies have shown that feeding probiotics to dogs who are suffering from diarrhea resolves the diarrhea almost twice as quickly as when diarrhea is managed without the use of probiotics. Veterinarians often prescribe probiotics to be used in conjunction with antibiotics to decrease the likelihood that the dog will experience antibiotic-related disruption in gastrointestinal bacteria populations and thereby decrease the likelihood that the chosen antibiotic will cause intestinal upset. 

We commonly consume yogurt for the benefits it exerts on our own digestive health. However, yogurt may not have the same benefit for dogs as it does for humans. Dogs have different species of healthy bacteria in their gut than people do. Probiotics designed specifically for dogs may have a higher success rate in controlling or reducing the frequency of canine digestive upset than probiotics designed for people. 

Feeding probiotics alone or in combination with prebiotics can have the effect of improving overall stool quality in our dogs as well as decreasing the frequency and severity of intestinal upset. If you would like to learn more about the potential benefits that probiotics and prebiotics can have on your dog’s digestive health, please contact your veterinarian.

-- Dr. Jody McMurray, D.V.M., B.Sc.