Aspergillosis
This fungus often presents in poultry, but non-poultry birds are also affected. In most cases this issue is seen after hatching/brooding due to inhalation of fungal spores from contaminated equipment. Respiratory signs are often seen with changes to the "voice" or crow of the patient. Infection is often in those animals who are immune suppressed or exposed to high spore counts.
Diagnosis can be very difficult without a post mortem as clinical signs are variable on non specific. However a fungal culture of any infected tissue is quit easy.
This case was referred to me. A free range chicken farm presented with a large amount of birds sick and dying. Clinical signs were as follows:
1) Gasping and difficulty breathing
2) Nervous signs such as gait issues or head tilts
3) Eye swellings with discharge
4) Post mortem showed white nodules on the air sacs, trachea, sinuses, intestines, etc
5) High, point source, mortality with variable morbidity.
6) Drop in egg production
Treatment is expensive and is not always effective with many anti fungal chemicals being very toxic and a slim margin of dosing. Individual birds can be treated systemically with a range of products and under vet supervision ideally.
Preventing spread in a flock takes the administration of copper sulphate. It can be applied to drinking water and sprayed on the ground.
As with all things...prevention is key. Be aware that fungal growth accelerates in warm and wet environments. Hygiene is key with regular and thorough cleaning of hatchers, waters, feeders, fans etc.
In this case, a large and recent deposit of mulch was applied to the ranging area and may have caused the outbreak.
