RETROSPECTIVE STUDY OF ASPERGILLOSIS IN JUVENILE FALCONS IN UNITED ARAB EMIRATES: PREVALENCE AND EFFECT OF...

Area of Science:

• Avian Medicine
• Veterinary Mycology
• Wildlife Health

Background:

• Aspergillosis is a significant disease affecting falcons in the Middle East.
• Clinical observations suggest gyrfalcons (Falco rusticolus) are highly susceptible, with hybrids potentially being more resistant.

Purpose of the Study:

• To investigate the prevalence of aspergillosis in different falcon species and their hybrids.
• To evaluate the clinical hypothesis regarding gyrfalcon susceptibility and hybrid resistance to aspergillosis.

Main Methods:

• Retrospective analysis of endoscopic results from 3,754 captive-bred juvenile falcons over 14 years.
• Inclusion of a control cohort from Dubai Falcon Center for genetic origin verification.
• Diagnosis of aspergillosis based on endoscopic findings.

Main Results:

• Overall aspergillosis prevalence was 24%, with gyrfalcons (27%) showing higher prevalence than peregrine falcons (18%).
• No significant difference in prevalence between total hybrid and total purebred populations.
• Gyrfalcon hybrids, especially gyrfalcon × peregrine (20%), demonstrated greater resistance than purebred gyrfalcons.

Conclusions:

• Gyrfalcons are indeed more susceptible to aspergillosis than peregrine falcons.
• The gyrfalcon × peregrine hybrid exhibits superior resistance to aspergillosis compared to purebred gyrfalcons.
• Outbreeding depression was observed in gyrfalcon × saker hybrids, indicating increased susceptibility.