Yoghurt as a probiotic supplement for pets?

The awareness of the beneficial health properties associated with probiotics has grown over the last few years. Many of the trends seen in the human sector are transferred to the pet market because of the increasing humanization of pets. However, is it actually beneficial to use yoghurt as a probiotic supplement for pets?

What are probiotics?

Probiotics are defined as: “a live microbial feed supplement which beneficially affects the host animal by improving its intestinal microbial balance” (Fuller 1989). Already present in the intestinal system of all animals and humans, probiotics are necessary for the digestion of nutrients and the balance of the intestinal microflora. Probiotics have proven beneficial in providing preventative and supportive care for both humans and pets. Some of the ways in which probiotics can be helpful are:

• Reduction of the symptoms of stress.
• Reduction of diarrhoea and other digestive upsets.
• Improvement of immunity and resistance to disease.
• Improvement of digestion.
• Improvement of skin and coat condition.
• Maintenance of a balanced microflora.

(Tuohy et al. 2003, Wynn 2009, Veir et al. 2007 and Grajek et al. 2005)

The ideal probiotic

When it comes to securing the health claims of probiotics it is of the utmost importance to get enough live organisms to the place in the intestines where they
are needed. For the probiotic bacteria to reach the intestinal tract in adequate numbers, they must be able to survive transit time through the acidic environment of the stomach and persist in the presence of bile and other digestive enzymes. In order to be used safely, probiotic supplements must also be non-pathogenic, non-toxic, not be able to transfer antibiotic resistance and be able to maintain genetic stability (Grajek et al. 2005 and Marcinakova et al. 2006).

Why not yoghurt

There is a growing tendency towards using live yoghurts as probiotic supplements for humans, and many people seem to think that human products are soothed for pets as well. However, there are some important disadvantages associated with using yoghurt for pets. The actual strains of microorganisms contained within live yoghurts are often chosen for taste and textural properties rather than actual probiotic benefits. Another problem with yoghurt is that most of it is pasteurized. Pasteurization is a process of heating designed to kill off harmful microorganisms, but it will often also kill the probiotic bacteria since many of them are heat-sensible. The concentration of live microorganisms present in yoghurt is therefore usually unknown, will tend to be relatively low and depend on the freshness of the yoghurt combined with the conditions under which it has been stored.

Lactose intolerance

A very important point also to be aware off is the fact that most pets are lactose intolerant, although there might be differences in the sensitivity level between animals. Breakdown of lactose requires lactase. The activity of lactase declines as pets reaches adulthood, which means there are not sufficient amounts of lactase present in the intestinal system of adult dogs and cats to handle the large quantities of lactose found in dairy products. Incomplete digestion of lactase causes upsets and can lead to the development of diarrhoea (Case et al. 2011).

Diarrhoea causes damage to the mucosa of the intestinal system and many of the enzymes required for the breakdown of e.g. lactose are lost. The intestinal system needs one to two weeks to restore to normal activity, which is why feeding pets dairy products during or after episodes of diarrhoea might even make matters worse (Hand et al. 2010).

Other than that, most dairy products contain deficiencies or excess of different nutrients and may contribute to dietary imbalances if large amounts are added to an otherwise adequate normal diet (Case et al. 2011).

Be aware of Xylitol

Pure yoghurt does not pose any threat to pets concerning toxicity. However, many of the yoghurts produced for human consumption contain xylitol which is an artificial sweetener and extremely toxic for dogs. Xylitol consumption can cause serious, even life-threatening symptoms in pets, especially dogs. Xylitol has long been known to cause hypoglycemia (low blood sugar) in dogs. However, more recent studies have shown that it can potentially cause acute liver failure (Piscitelli et al. 2010).

After xylitol ingestion, vomiting is usually the initial sign. Hypoglycemia may develop within 30 to 60 minutes and clinical signs may progress rapidly from lethargy to ataxia, collapse and even seizures. Case reports show dogs developing elevated liver enzymes within 12 to 24 hours and in a specific case report regarding eight dogs five of the dogs where either euthanized or died following xylitol ingestion (Dunayer 2006).

Cases of xylitol toxicity in dogs are likely to increase as human use of xylitol-containing products becomes more common, but one way to decrease the cases is to avoid using yoghurt as a probiotic supplement for pets, and instead use specific species-formulated supplements or even better high-quality pet-food containing probiotics.

By Therese G. Hosbjerg, DVM and Technical manager at Bacterfield GMBH

References

• Case L.P., Daristotle L., Hayek M.G. and Raasch M.F. (2011): Canine and Feline Nutrition. A Resource for Companion Animal Professionals. 3rd Edition. Mosby Elsevier, Missouri, United States of America.
• Dunayer, E.K., (2006): New findings on the effects of xylitol ingestion in dogs. Veterinary Medicine, 12: 791-797.
• Fuller R. (1989): A Rewiev – Probiotics in man and Animals. Journal of Applied Bacteriology, 66: 365-378.
• Grajek W., Olejnik A. and Sip A. (2005): Probiotics, prebiotics and antioxidants as functional foods. Acta Biochimica Polonica, Vol. 52, No. 3, 665-671.
• Hand, M.S., Thatcher, C.D. et al. (2010): Small Animal Clinical Nutrition. 5th Edition. Mark Morris Institute, Kansas, United States of America.
• Marcinakova M., Simonova M., Strompfova V. and Laukova A. (2006): Oral Application of Enterococcus faecium Strain EE3 in healthy dogs. Folia Microbiol., 51(3), 239-242.
• Piscitelli C.M., Dunayer E.K. and Aumann M. (2010): Xylitol Toxicity in Dogs. Compendium: Continuing Education for Veterinarians, 32(2), E1-E4.
• Tuohy K.M., Probert H.M., Smejkal C.W. and Gibson G.R.: Using probiotics and prebiotics to improve gut health. Drugs Discovery Today, Vol. 8, No. 15, 692-700
• Veir J.K., Knorr R., Cavadini C. et al. (2007): Effect of Supplementation with Enterococcus faecium (SF68) on Immune Functions in Cats. Veterinary Therapeutics, Vol. 8, No. 4, 229-238.
• Wynn S. (2009): Probiotics in veterinary practice. JAVMA, Vol. 234, No. 5. Vet Med Today: Timely Topics in Nutrition, 606-613.