## Overview Large colon impaction is obstruction of the large colon by firm, dehydrated feed material, most often at the pelvic flexure. It is one of the most common causes of colic. Horses show mild to moderate pain, reduced manure output, and a firm mass that can often be felt on rectal examination. ## Causes Dehydration, poor dental function, sudden feed changes, limited water access, or reduced exercise. ## Diagnosis Rectal palpation of a firm impaction, ultrasound, and clinical signs of mild colic with decreased fecal output. ## Treatment Intravenous or oral fluids, analgesics, and lubricants. Most cases resolve medically within one to several days. Surgery is rarely needed. ## Recovery and Prognosis Excellent with prompt medical treatment. Recurrence is possible if risk factors persist. ## Prevention Constant access to fresh water, regular dental care, gradual feed changes, and consistent exercise.
mild to moderate colic; decreased fecal output; firm mass palpable at the pelvic flexure; dehydration
## Overview Large colon impaction is obstruction of the large colon by firm, dehydrated feed material, most often at the pelvic flexure. It is one of the most common causes of colic. Horses show mild to moderate pain, reduced manure output, and a firm mass that can often be felt on rectal examination. ## Causes Dehydration, poor dental function, sudden feed changes, limited water access, or reduced exercise. ## Diagnosis Rectal palpation of a firm impaction, ultrasound, and clinical signs of mild colic with decreased fecal output. ## Treatment Intravenous or oral fluids, analgesics, and lubricants. Most cases resolve medically within one to several days. Surgery is rarely needed. ## Recovery and Prognosis Excellent with prompt medical treatment. Recurrence is possible if risk factors persist. ## Prevention Constant access to fresh water, regular dental care, gradual feed changes, and consistent exercise.
mild to moderate colic; decreased fecal output; firm mass palpable at the pelvic flexure; dehydration