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  • Probiotics are beneficial bacteria that compete with harmful bacteria to restore the proper bacterial balance in the intestines of dogs and cats.
  • Probiotics are administered when an overgrowth of harmful bacteria result in diarrhea, vomiting, or gas.
  • Different probiotic bacteria have different effects on the digestive tract.
  • Because probiotic products on the market can vary in their integrity and efficacy, it’s best to consult your veterinarian about the proper probiotic for your pet.

During the birthing and nursing processes, puppies and kittens ingest bacteria that make themselves at home in the intestines. Some of these bacteria are beneficial to the pet, and some are potentially harmful. The beneficial bacteria help digest food, produce energy for the cells lining the digestive tract, and help with immune function. They also help keep the potentially harmful bacteria to a minimum.

It’s been estimated that there are up to 500 different kinds of bacteria in a dog or cat’s digestive tract. Under normal conditions, the beneficial and harmful bacteria strike a balance, so there are no detrimental effects to the pet. However, a number of factors can cause an overgrowth of harmful bacteria, such as disease, parasites, antibiotics, old age, stress, and food changes. The resulting imbalance can lead to diarrhea, vomiting, and gas.

What Are Probiotics?

By definition, probiotics are live microorganisms, such as bacteria or yeast, which provide a health benefit to the pet when given in adequate amounts. These probiotics are available as supplements or as part of some diets. When pets experience an overgrowth of potentially harmful bacteria, probiotics are administered to increase the numbers of beneficial bacteria and restore the balance in the digestive tract.

How Do Probiotics Work?

When beneficial bacteria are added to the digestive tract, they adhere to the walls of the intestines, so there is less room for the harmful bacteria to colonize there. They also compete for food, and alter the pH of the environment, making it less conducive to the survival of harmful bacteria. By restoring the balance of bacteria, probiotics help relieve the diarrhea, vomiting or gas the pet may be experiencing.

In humans, probiotics may also play a role in helping control allergic conditions, immune diseases, dental disease, as well as some nervous system problems. However, there has been no research to show that probiotics have the same effects in pets. Never give a human probiotic product to your pet unless instructed to do so by your veterinarian. 

Why Would My Pet Need Probiotics?

Under normal conditions, a healthy pet shouldn’t need probiotics, because the intestinal tract can usually maintain the proper bacterial balance on its own. However, antibiotics, stress, and other factors can alter this balance. This can lead to an increase in harmful bacteria and resulting intestinal problems in some pets. Your veterinarian may recommend probiotics if your pet is showing signs of an overgrowth of harmful bacteria.

How Do I Choose A Probiotic?

Different types of bacteria exert different effects in the digestive tract. That’s why probiotics used in humans may not have the same beneficial effects in pets.

Also, remember that probiotics are living organisms. They must survive not only the manufacturing process, but also storage under certain conditions. A recent study showed that many of the probiotic products on the market did not have live organisms in the quantity specified on the label. These bacteria must also survive the acid environment of the stomach, so that they can have their effect in the intestinal tract.

That is why it’s best to ask your veterinarian for advice about probiotics. He or she can recommend a product that is appropriate for pets, and is produced by a reputable manufacturer.