What is Colitis?
The rapid onset of diarrhoea, with horses often being normal one day then becoming ill and passing watery diarrhoea the next. It is called Colitis as it is the large colon and/or caecum that is involved.
The large colon of horses is full of microorganisms that help the horse digest and absorb food. One type of bacteria has a toxin (endotoxin) attached to its cell wall. In the normal horse, this is not a problem but if there is compromise to the gut wall these bacteria and endotoxins are absorbed into the blood stream and can cause a massive inflammatory response (endotoxaemia) in other organs and tissues. The large colon of the horse is responsible for absorbing a large volume of fluid back into the circulation, so losses can quickly lead to severe dehydration.
Acute diarrhoea in horses can be life-threatening and requires immediate veterinary attention.
How do horses get Colitis?
Factors that are thought to predispose horses to acute diarrhea include stressful situations such as transportation, new environments, rapidly changed management, excessive grain engorgement and antibiotics. It is the overgrowth of bacteria and damage to the gut wall that leads to the diarrhoea and these horses quickly deteriorate.
What are the Signs and Symptoms of Colitis?
Horses that have developed acute diarrhea will often appear dull, have a high heart rate, injected gums, increased temperature and have signs of dehydration. These horses can also show signs of colic, often preceding the diarrhoea, but they might also remain uncomfortable throughout the disease. On a blood profile, these horses often have extremely low white cell counts and can also have signs of kidney damage due to the poor circulation to the kidneys.
How is Colitis Treated?
Treatment needs to be rapid these horses will often need large volumes of intravenous fluids to replace deficits and keep up with the losses in diarrhoea. Careful use of non-steroidal anti-inflammatory drugs such as flunixin is often used to provide pain relief and to reduce the effects of the endotoxin. Complications of Colitis include laminitis and therefore constant icing of the distal limbs and sole support is required until the endotoxaemia has resolved.
As the cause of the diarrhoea is often infectious, horses are required to be isolated and proper biosecurity protocols observed to avoid infection of other horses, as well as their handlers.
On a positive note, recovery and return to athletic function of these horses is usually very good, provided there has been no secondary effects such as laminitis or renal failure.
My Horse has been referred to U-Vet Equine Centre for Colitis, what do should I do next?
You can contact U-Vet Werribee Equine Centre on 03 9731 2268 and speak to one of our friendly receptionists who will make sure we have all the relevant information for your horse including your referring veterinarian details.
When you arrive with your horse it is important to leave your horse on the float and come see Equine Reception first. One of our dedicated Equine Nurses will then assist you to admit your horse into our isolation stables. As Colitis is often infectious it is important the correct biosecurity measures are taken. Once your horse has been admitted to hospital our team of Specialist Equine Medicine Veterinarians will be in regular contact with you and your referring veterinarian to work out the best plan of action for treatment. The U-Vet Werribee Equine Centre is a 24 hour hospital, while your horse is in hospital with us you can be assured they are receiving the best care and treatment available 24 hours of the day.