Which condition is often associated with the respiratory system of horses due to poor ventilation?

Heaves, also known as recurrent airway obstruction (RAO), is a chronic respiratory condition in horses that is often linked to poor ventilation, particularly in stabled horses exposed to dusty environments such as hay and bedding. When a horse is kept in a poorly ventilated area, irritants can accumulate, leading to inflammation and constriction of the airways. This results in coughing, nasal discharge, and difficulty breathing, which are characteristic signs of heaves.

The other conditions mentioned do not directly relate to poor ventilation. Pneumonia is primarily an infection of the lungs and can be influenced by various factors, including pathogens and immune response, rather than ventilation alone. Gastric ulcers primarily stem from diet and stress rather than respiratory factors. Wobbler Syndrome affects the cervical spine and is related to developmental issues rather than respiratory health. Thus, heaves is specifically the condition that associates closely with the effects of inadequate air quality and ventilation in the environment where a horse is kept.