For the Health of It
6 • Walking On
Probiotics in horses : Potential benefits and how to choose the right product
Reprinted with permission from Volume 31 , Number 3 of Equine Disease Quarterly
Probiotics have the potential to positively impact gastrointestinal ( GI ) health , decrease adverse effects of antimicrobials on intestinal microbial communities and improve our ability to prevent or treat colic and colitis . Additionally , probiotics improve our capacity to treat diseases outside of the GI tract including allergies , neurological disorders and respiratory disease . This is because probiotics have the potential to modify the population of bacteria present within the GI tract , improve intestinal barrier function ( i . e ., “ decrease gastrointestinal leakiness ”) and decrease the presence of pathogenic bacteria like Salmonella . They may also interact with the immune system , which can have positive ( or negative ) effects beyond those that occur locally within the GI tract .
According to the World Health Organization and Food and Agricultural Organization , probiotics are defined as living microorganisms , which when delivered in adequate amounts , confer a health benefit to the host . Based on this definition , there are three criteria that products , marketed as probiotics , should meet : ( 1 ) they should contain live microorganisms , ( 2 ) the microorganisms should be delivered in adequate numbers and ( 3 ) the microorganisms should do something beneficial for the horse . Below , each of these criteria are broken down and discussed in reference to the horse , and advice is provided on how to look for a product that meets as many of these criteria as possible .
The first criterion is that the product contains live microorganisms . There are several potential challenges that microorganisms ( typically , bacteria and / or yeast ) in probiotics must overcome to remain viable in probiotics . Most consumers are looking for probiotics to improve “ hind gut ” or cecum and / or colonic health , thus microorganisms must survive transit through the horse ’ s acidic stomach and small intestine to reach the cecum and / or colon . Bacteria and yeast are not invincible and thus , their viability can be adversely affected during transit . Additionally , they must survive many conditions that are out of the consumer ’ s control , such as manufacturing , shipment and storage .
To improve probiotic viability , choose a product that lists both storage instructions and an expiration date . Then , follow the storage instructions appropriately . Many companies recommend storing their probiotics in a “ cool and dry place .” While this is not specific , products likely should not experience the extremes of summer and winter in a barn .
Second , look for products that advertise “ enteric protection ” or a mechanism to help the microorganisms survive transit through the acidic stomach and small intestine to reach the cecum and colon .
If you choose a product without enteric protection factors , then it is beneficial to administer the probiotic when hay ( or other roughage ) is fed .
The second criterion is that microorganisms should be available in adequate numbers . Unfortunately , we do not have a definitive answer for this topic in horses . In adult humans , it is recommended to use 1 x 106- 108 colony forming units ( CFU ) of microorganisms at the time of consumption . It would seem intuitive that adult horses should receive at least this many , if not more , CFU per dose given the size of the horse and the horse ’ s gastrointestinal ( GI ) tract in comparison to that of a human . However , currently , we do not know the optimal dose to administer a horse . Until an answer has been determined , consider choosing products that provide a total number of CFUs per microorganism and per dose for their product . A repeated concern for probiotics is that independent research has identified discrepancies between label claims and actual contents when certain products have been evaluated , raising concerns for quality control . Thus , finding a company that is willing to provide information on quality control and testing would also be desirable .
Finally , the product should provide a health benefit to the horse . In humans , a large body of research has been conducted to