Temporal dynamics of airborne fungal succession and detection of azole-resistant Aspergillus fumigatus in a poultry farm over a nine-week production cycle

This longitudinal study assessed airborne fungal ecology and azole resistance in A. fumigatus sensu lato within a commercial poultry facility in Taif, Saudi Arabia, across a complete nine-week broiler grow-out cycle. Weekly aeromycological sampling (189 SDA plates) identified 29 fungal species (11 genera) from 450 isolates, dominated by A. flavus sensu lato (246.44 CFU/m³), A. niger sensu lato (229.44 CFU/m³), and Alternaria alternata (183.33 CFU/m³). Total fungal concentrations peaked at 336.67 CFU/m³ in Week 7. Among 35 A. fumigatus sensu lato isolates (TUAf102-TUAf136), disk diffusion testing revealed voriconazole (17.1%; 6/35), itraconazole (20%; 7/35), posaconazole (25.7%; 9/35), and fluconazole (22.9%; 8/35) resistance, plus multidrug resistance (8.6%; 3/35) from Week 1 onset. Mid-cycle resistance peaks (Weeks 5-8) coincided with maximum fungal loads, though sampling variability limits definitive trends. These findings confirm poultry housing as reservoirs of antifungal-resistant aspergilli, warranting cyp51A genotyping, azole residue monitoring, and One Health surveillance to protect occupational health and antimicrobial efficacy in intensive production systems.