June Case of the Month: Not Your Average Gut Feeling

There are many causes of diarrhea in the horse. We can submit fecal samples to look for infectious agents such as E coli, Salmonella, Clostridium etc. Not often does this test come back positive for any infectious agent, but on this occasion, the test came back positive for Cryptosporidium. 

Cryptosporidium is a protozoan, commonly causing severe and occasionally fatal disease in calves, and uncommonly in foals. It causes profuse watery diarrhea and the neonates can succumb to secondary dehydration if they don’t receive adequate supportive fluid therapy. Although there is no specific treatment for this protozoan infection, generally the disease is self-limiting and the animal will clear the infection itself. However, it is highly contagious and will spread it easily to other susceptible animals (including stressed out vet students).

What makes this case particularly unusual is that we discovered this protozoan in an ADULT horse. The horse came from a cattle farm in the Prairies, and suffered from chronic diarrhea for several months before they was tested. We assumed the horse was immunocompromised and decided to perform a fecal transfaunation to help boost the microflora in the gut. The good news is that the fecal transfaunation was successful, the diarrhea has resolved and the repeated tests were negative for Cryptosporidium.