Which clinical signs are most suggestive of meconium impaction in a foal?

• A. Tenesmus, stranguria, passing feces
• B. Lethargy, tachypnea, pale mucous membranes
• C. Diarrhea, vomiting, fever
• D. Cough, nasal discharge, sneezing

Answer: (A)

Meconium impaction in a newborn foal typically presents as colic-type discomfort caused by obstruction at the distal gut. The most telling sign is straining to defecate, or tenesmus, as the foal tries to pass the thick, dry meconium. Because the blockage prevents normal stool passage, you often see the foal working to defecate with little or no stool produced, and other signs of abdominal pain such as restlessness or a tense stance may accompany this. Stranguria can appear because the foal’s overall abdominal discomfort affects its posture and efforts, but the key feature is the painful defecation effort. In contrast, signs like lethargy with rapid breathing and pale mucous membranes, diarrhea with vomiting and fever, or respiratory signs such as coughing and nasal discharge are not typical for a straightforward meconium impaction and point toward other problems. So the signs most suggestive of meconium impaction are the painful defecation attempt (tenesmus) and related abnormal defecation pattern, often with little or no stool passed.