The phrase “equine gastrointestinal disease” can bring to mind images of colicky, sweaty, painful horses pawing and rolling. Sometimes diarrhea, however, can be equally uncomfortable and life-threatening for the horse due to secondary development of laminitis and vascular thrombosis (a blood clot). Worse, diagnosing the cause of diarrhea and stopping the spread of disease can be fraught with frustration because first responders currently lack optimal management and prevention practices.

During his presentation at the 2016 American Association of Equine Practitioners Convention, held Dec. 3-7 in Orlando, Florida, Scott Weese, DVM, DVSc, Dipl. ACVIM, a professor in the departments of Pathobiology and Infection Control at the Ontario Veterinary College, in Canada, provided key tips for handling potentially explosive situations … as in infectious diarrhea.

When walking into an equine facility with a suspected case of gastrointestinal (GI) disease, the most important step isn’t making an immediate definitive diagnosis, said Weese.

Rather, it is separating the clinically affected horses from the rest of the herd. “It is imperative to reduce transmission of pathogens (disease causing organisms) by personnel, fomites (inanimate objects), or other animals,” he said.

Step two, said Weese, is cohorting, which involves separating horses into groups based on their risk status.

For example, segregate horses based on their risk status: diseased, exposed, and unexposed. Even within the diseased and exposed groups, individual isolation is ideal, although often not implemented at many facilities. When in doubt regarding which horses should go into which groups, default to the highest risk group that is reasonable.

Once you’ve grouped horses appropriately and instituted treatment, infection control response can continue. Such strategies include:

  • Establishing an investigation team;
  • Conducting diagnostic testing;
  • Making containment and isolation recommendations; and
  • After the final quarantine is lifted, reviewing the outbreak to prevent future issues.

Weese described details regarding each of these disease-mitigating topics in his convention Proceedings abstract.

Summing up, Weese suggested implementing appropriate biosecurity measures pre-emptively, as infectious disease is an ever-present risk with horses.

“A proactive infection control program implemented with the assistance of a veterinarian can limit the introduction of pathogens, reduce the risk of sporadic disease, and reduce the risk of outbreaks that develop in response to pathogen entry,” he said.