What is a primary sign of an upper respiratory infection like rhinopneumonia in horses?

Nasal discharge is a primary sign of an upper respiratory infection such as rhinopneumonia in horses. This condition typically causes inflammation and irritation in the respiratory tract, leading to the production of mucus. This mucus can accumulate, resulting in a noticeable discharge from the nose. The presence of nasal discharge indicates that the horse's body is responding to an infection, as it attempts to rid itself of pathogens and irritants.

While fever, severe coughing, and difficulty swallowing can also be associated with upper respiratory infections, nasal discharge is one of the most immediate and recognizable symptoms. It provides a clear indication of the inflammatory process occurring in the upper respiratory tract, which is characteristic of rhinopneumonia and other similar infections. Thus, recognizing this sign is essential for the early identification and management of respiratory issues in horses.