A healthy respiratory system is of prime importance for the performance of our horses. Respiratory problems are a common condition. Competition horses, in particular, are particularly sensitive to this because of long transports, stress (reduced resistance), and numerous contacts with foreign horses. When a horse coughs, the mucous membranes are irritated and mucus production increases. The mucus becomes increasingly tough and gets stuck in the horse’s airways. This irritation and / or increased mucus production triggers the cough reflex. Breathing becomes more difficult due to the amount of mucus that builds up in the airways. The causes of dry cough in horses can vary from dust, allergies to thermal stimuli such as cold and wetness. All these causes put a strain on the immune system in horses.