Diarrhoea (ENTERITIS)
Enteritis is inflammation of the intestines and usually causes diarrhoea as the main sign. Diarrhoea can be seen in horses of all ages and types of horse and there are many causes. The most common cause of diarrhoea is due to a change in nutrition e.g. horses moved on to rich pasture or being fed richer food. The simple way to treat this cause of diarrhoea is to correct this change in nutrition, however, if the horse seems sick i.e. is depressed and off food a vet should be contacted.
Clinical signs
The most obvious sign of enteritis is diarrhoea, which can be profuse and watery. Horses may also be dull and depressed, be off their food and have signs of colic. Due to the amount of water that can be lost in severe cases of diarrhoea animals may also become dehydrated. Animals with severe enteritis can become endotoxaemic. This occurs when toxins are released from the inflamed intestines into the bloodstream. When horses become toxic they become very sick as they go into shock and have deep red/ purple mucous membranes and an increased heart rate. These horses must be treated immediately to try to boost the circulatory system.
Diagnosis
A blood sample should be taken to assess the degree of inflammation and dehydration. A sample of the droppings can be taken to culture bacteria or to look for the presence of worm larvae or eggs. It is often the case that a diagnosis cannot be made initially and the diagnostic tests are used mainly to assess the degree of inflammation and dehydration so that treatment can be aimed at stabilising the animal.
Treatment
If an infectious cause of diarrhoea is suspected e.g. salmonella, the affected animal should be placed in strict isolation. A wormer should be given if the worming history is not clear or it is known that the horse has not been wormed. A vet should be contacted before a wormer is given. Fluids can be given intravenously if the horse is dehydrated. Flunixin, an anti-inflammatory drug, is often given to try and prevent or counteract endotoxaemia. Polymixin B is also occasionally used to neutralise endotoxins. Antibiotics can be given if horses are septicaemic.