Fecal Water Syndrome is a condition in which horses produce normal feces, but before, during, or after defecation, water freely runs out of the anus. This water can also be produced independently from bowel movements. Fecal Water Syndrome is not associated with weight loss, colic, or other medical issues, but it can cause management issues with the skin of the hind legs or tail due to irritation. It can also mean stall bedding needs to be changed more often resulting in more work for the owner.
There is no clear data on why Fecal Water Syndrome occurs but there are many theories on the cause and which groups of horses seem to be affected more often. Some theories are that it can be brought on by dental disease or a heavy parasite burden. A German study was carried out to test these theories and found that neither seemed to have an impact, rather it was found to be more likely to occur:
- In horses that are of a lower rank in the herd
- In horses with anxiety
- In winter where horses are confined to a smaller area than they are used to
- In geldings
- In Paint horses
- In older horses
- In horses recovering from severe colitis (infection of the large intestine)
While the German study seemed to identify some specifically affected groups, any horse of any breed or age can experience Fecal Water Syndrome. Another theory that doesn’t have concrete data but appears to be linked, is changes in the hindgut such as increased motility, strong gut contractions, and inflammation. This theory is supported by the fact that changes in motility of the hindgut impairs its ability to absorb water.
While there are no specific treatments for Fecal Water Syndrome, dietary and environmental changes can be made to help reduce occurrences. These changes should be discussed with a veterinarian after a comprehensive exam to determine what will work best for that specific horse. Regardless of the prescribed changes, keep in mind they should be made gradually to reduce anxiety and stress which could further contribute to occurrences.