When fungi are present in forage and feed in large numbers, they can greatly affect the respiratory system of all animals, especially equines and therefore, equine performance. One of the most common groups of pathogenic fungi found in harvested forage and feed is Aspergillus. Aspergillus is one of the main causes of Recurrent Airway Obstruction (RAO), Exercise Induced Pulmonary Haemorrhage (EIPH), and immune suppression, in equines, all of which can greatly affect equine performance. These fungi also affect all other livestock when there has been long-term exposure and its effects may be observed mainly as immune suppression in these cases. The Environment and Nutrition department provides fungal enumeration to assess the presence and quantity of both pathogenic and non-pathogenic microbes.