Changes

==Pathogenesis==

==Pathogenesis==

In dogs, spores are inhaled from the environment leading to fungal colonisation of the nasal cavities. Following their deposition in tissue and recognition by phagocytes an inflammatory response is triggered. Haemolytic and dermonecrotic toxins as well as fungal protease and elastase are released leading to tissue damage.

In dogs, spores are inhaled from the environment leading to fungal colonisation of the nasal cavities. Following their deposition in tissue and recognition by phagocytes an inflammatory response is triggered. Haemolytic and dermonecrotic toxins as well as fungal protease and elastase are released leading to tissue damage.

In horses, the pathogenesis of guttural pouch mycosis is largely unknown but is thought to relate to damage to the mucosal layer of the pouches by trauma or infection. This enables opportunistic Aspergillus fungi to invade into the damaged tissue.  

In horses, the pathogenesis of guttural pouch mycosis is largely unknown but is thought to relate to damage to the mucosal layer of the pouches by trauma or infection. This enables opportunistic ''Aspergillus'' fungi to invade and colonise the damaged tissue.  

==Clinical signs and features==

==Clinical signs and features==

===Horses===

===Horses===

In the horse, Aspergillus most commonly affects the guttural pouches but infection may also lead to abortion, keratomycosis and rarely pulmonary aspergillosis. Guttural pouch mycosis is characterised by spontaneous epistaxis (often in a resting horse) as a result of fungal erosion of the internal carotid artery. Other clinical signs include nasal discharge and dysphagia. Mycotic plaques are usually located on the caudodorsal aspect of the medial guttural pouch.

In the horse, Aspergillus most commonly affects the guttural pouches but infection may also lead to abortion, keratomycosis and rarely pulmonary aspergillosis. There is no age, sex or breed predisposition for guttural pouch mycosis and both left and right pouches are affected with equal frequency. Guttural pouch mycosis is characterised by spontaneous epistaxis (often in a resting horse) as a result of fungal erosion of the internal carotid artery. Other clinical signs include nasal discharge and dysphagia. Mycotic plaques are usually located on the caudodorsal aspect of the medial guttural pouch.

===Dogs===

===Dogs===

==Treatment==

==Treatment==

In dogs, the treatment of choice is topical application of the anti-fungal agent Clotrimazole. It is admnistered for one hour under general anaesthetic via indwelling catheters placed in the frontal sinus. Several treatments may be required. For cases that are non-responsive to Clotrimazole, treatment with Enilconazole may be attempted but this is associated with a higher complication rate.

In dogs, the treatment of choice is topical application of the anti-fungal agent Clotrimazole. It is admnistered for one hour under general anaesthetic via indwelling catheters placed in the frontal sinus. Several treatments may be required. For cases that are non-responsive to Clotrimazole, treatment with Enilconazole may be attempted but this is associated with a higher complication rate.  

In cattle, antifungal agents are currently unlicensed and management of the disease usually relies on preventative measures such as ensuring clean bedding and good husbandry.  

In cattle, antifungal agents are currently unlicensed and management of the disease usually relies on preventative measures such as ensuring clean bedding and good husbandry.  

In the horse, trans-arterial coil embolisation under fluoroscopic guidance is performed in order to cause internal occlusion of the affected arteries.  

In the horse, trans-arterial coil embolisation under fluoroscopic guidance is performed in order to cause internal occlusion of the affected arteries.