by Eric Halloran

Created on: October 10, 2009

Aspergillosis is an insidious fungus that can rapidly kill a bird by invading it's lungs. I know this firsthand having lost my first goshawk to this disease.

The disease is caused by spores of one of several varieties of the Aspergillus fungus which is highly prevalent in damp wood over most of the world. Birds in captivity and under stress seem to be more susceptible to an infection by the spores. Among birds of prey, the accipiters, or woodlands hawks, and especially, goshawks are struck with the disease more frequently than falcons and other species. The prognosis for treatment is very poor. The standard treatment is amphoteracin B. This is usually introduced by injection, but can be delivered through use of a fogging machine in a small enclosed area. I have also heard of the aerosol form of the drug being delivered to a bird using the standard gas apparatus used for anaesthesia. This device looks like a glass bell jar with a partial flexible diaphragm over the large opening. A hose connected to an opening at at the apex of the device is used to transmit the aerosol preparation of the anti fungal agent. The flexible opening in the diaphragm is slipped over the birds head and eased down the neck.

In most cases that I am aware of the disease is discovered too late for treatment to be effective. This is because symptoms are subtle and tend to be easily overlooked. Birds in captivity will appear to be more tame and less nervous than usual. This is very uncharacteristic of a goshawk, but is still can be missed. Infected birds often are observed to drink more than usual. Towards the end there is rapid weight loss through dehydration. An autopsy reveals extensive invasion of a grayish, dusty mold throughout the lungs and body cavities.

Infinitely more effective than treatment is prevention. The litter in the mews or cage should be changed frequently. All measures should be pursued to weatherize the mews (building) so the interior can be kept dry. Since the Aspergillus mold grows best on wood, alternatives to sawdust as a litter should be sought, especially for the keeping of Accipiters. Care should be taken to keep birds as stress-free as possible. This includes positioning the building so that the principal window with the preferred south or southeast orientation looks out on a peaceful scene with a minimum of human activity. Stress can also be minimized by maintaining the bird on a healthy diet.

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