What are probiotics and prebiotics?
Probiotics are live bacteria, generally used to improve the gut flora composition, when there is suspicion that the usual beneficial bacteria populations are altered.
Prebiotics are non-live compounds which are used to promote the growth of microorganisms seen as beneficial for health.
Probiotics and prebiotics are often, but not always, used concomitantly in commercial preparations, and these preparations are then called synbiotics. Prebiotics and, to a lesser degree probiotics, can be added as ingredients in a variety of commercial diets.
What are the indications to use probiotics/ prebiotics for my dog or cat?
These products have been used for many conditions or following antibiotic treatments, but are mainly used for management of patients with acute or chronic gut disease. Studies have shown that probiotics may shorten the duration of acute diarrhoea, especially for patients in kennels or shelters. Similar improvement has been seen with some form of chronic gut diseases, and a treatment trial with probiotics has been advocated by some specialists prior to performing further investigations in stable patients. Studies are lacking, however, to determine the ideal duration of treatment for each individual patient.
Improving the gut microflora may have more systemic effects as the intestinal microorganisms are thought to have a variety of roles, from digestion of nutrients and vitamins to production of beneficial compounds or regulation of the immune system. Although more studies are needed to assess the true effect of probiotics, some studies have suggested they may be beneficial for:
- Kidney function
- Liver function
- Allergic skin disease
- Gastro-intestinal signs following antibiotic treatment
- Constipation in cats
Of note, some of the studies only reported mild changes and specialists are still debating if the use of probiotics is clinically useful for some patients.
What are the risks in using probiotics/ prebiotics for my dog or cat?
Despite the fact that using probiotics/ prebiotics changes the flora and may have a more general influence on the rest of the body, there are currently no reported significant adverse effects in dogs and cats. This may be linked to the fact that most probiotics use a single bacteria species and/ or in relatively small quantity. There are theoretical risks of allergy to flavouring or stabilising products used in some probiotic preparations and this should be discussed with the clinician who is prescribing the probiotic.
In human medicine, concerns have been raised regarding the use of probiotics in patients with severe immune system compromise, but this remains speculative. Further studies are required to assess if subtle abnormalities can be observed in our pets when probiotics are used long-term, although it is currently accepted that this is very safe.
What is the best probiotic to use for cats and dogs?
There is no comparative study assessing which commercial probiotic is the best in any given situation. There are a variety of veterinary or human commercial probiotics which differ by the bacterial species (although the most commonly used bacteria in veterinary preparations is Enterococcus faecium), the quantity of bacteria, the adjunct of vitamins or prebiotics, and the presence of other stabilising compounds. The choice of probiotics to use must be discussed with the clinician in charge of your pet.
Can I use human food known to have prebiotic effects (e.g. kefir, yoghurt, sauerkraut)?
There is a paucity of information regarding the use of human ‘prebiotic’ food in dogs and cats. We do not currently recommend to try these as human gut flora does differ markedly with canine or feline gut flora and there are risks that this type of food may be associated with adverse reactions; such as fermentation in the gut with flatulence or abdomen discomfort. Chocolate, advocated as a prebiotic food, is toxic for cats and dogs.
Can my dog or cat take probiotics at the same time as antibiotics?
As stated previously, probiotic use can actually help recover a normal gut flora after antibiotic treatment. Although often life-saving medications, antibiotics not only fight a dangerous infection but can also have similar effect on ‘good’ bacteria. This can lead to diarrhoea, nausea, anorexia or signs of abdominal discomfort and probiotics have shown that they can protect against these signs.
When taking probiotics during an antibiotic treatment, it is important to avoid giving these two medications together to reduce the risk that the good bacteria in the probiotic are destroyed before having any beneficial effect. It is recommended to wait at least two hours between these two medications.