Which of the following is NOT a symptom of a cold in horses?

Severe pain is not a typical symptom of a cold in horses. A cold, or upper respiratory infection, usually presents with mild symptoms related to the respiratory tract. Common signs of a cold include nasal discharge, coughing, and general fatigue or weakness due to the body’s response to the infection. Nasal discharge can consist of clear, watery mucus that may become thicker as the infection progresses. Coughing is also a frequent symptom as the horse’s body attempts to clear irritation from the airways.

In contrast, severe pain is more indicative of other more serious conditions or illnesses, such as colic or severe infections, rather than a simple upper respiratory cold. Understanding the distinction between mild cold symptoms and more serious health issues is crucial for proper care and management of a horse's health.