Diagnosing and Managing Colitis (Colotyphlitis) in Horses and Enterocolitis in Foals

Diarrhoea – a few facts

The initiating cause of acute diarrhea in horses is not determined in more than 60% of cases, however, approximately 40% of horses have at least causal association, if we go to the time and expense of doing all the tests! Although this seems very expensive sometimes, it is really justified when you identify Salmonella species etc..

Diarrhoea is simply increased water content in the faeces - there may also be electrolyte secretion to absorption imbalances, as well as small to massive protein losses (changing oncotic pressures). When adult horses have enteritis, we rarely recognise this as diarrhoea (but may see it as duodenitis- proximal jejenitis with obtunded mentation, colic, fever, nasogastric reflux), as the adult large intestine has such an enormous capacity to absorb extra fluid.

The different mechanisms involved in diarrhea include:

1. hypersecretion
2. increased permeability (exudation)
3. malabsorption
4. abnormal motility

Inflammatory processes are nearly always involved in the bowel of horses presenting for severe, acute diarrhea.

In adults, if the “healthy” cecocolic intestinal flora is altered then it may result in acute, severe colotyphlitis. [...]