Alimentary System Foreign Body - Horse

See Colic Diagnosis in Horses

Medical Treatment of Colic in Horses

Description

Primary obstruction may occur due to the physical blockage of the gastrointestinal tract by ingested material such as baling twine, hair or fencing material. Ingestion of objects such as nails, wire or sharp stones may also lead to obstruction via the formation of an enterolith. The most common sites for foreign body obstruction are the small colon and at the junction of the right dorsal and transverse colon (due to the reduction in lumenal diameter at this point).

Signalment

Foreign body obstruction is most common in younger horses due to their often indiscriminate feeding habits. It may also occur in malnourished or starved horses with inadequate access to food.

Clinical signs

There are few pathognomonic features of foreign body ingestion in the horse and an accurate and thorough history is particularly important in suspected cases. Affected horses often present with signs of mild to moderate abdominal pain such as rolling, pawing and flank-watching. Other clinical signs may include inappetance, depression, absence or reduction in faecal output and abdominal distension.

Diagnosis

A history of ingestion of foreign material combined with clinical signs of abdominal pain, reduction in faecal output and dehydration is strongly suggestive of a non-strangulating obstruction. Rectal examination may reveal the presence of a foreign body but this is often unremarkable. Affected horses are generally unresponsive to medical management.

Treatment

Initially, the case may be difficult to distinguish from a large colon impaction and treatment in the early stages may consist of fluid therapy and administration of laxatives such as mineral oil. Some cases may resolve spontaneously in response to medical treatment but those that do not require surgical removal via laparotomy.

Prognosis

In longstanding cases, bowel rupture due to pressure necrosis or gas distension may occur and the prognosis for these horses is grave. The prognosis is good in horses that have undergone surgery to remove the obstruction early before cardiovascular deterioration.

References

• Rose, R. J., Hodgson, D. R. (2000) Manual of Equine Practice Elsevier Health Sciences

• Mair, T. S., Divers, T. J., Ducharme, N. G. (2002) Manual of Equine Gastroenterology Elsevier Health Sciences