2025, Vol. 5, Issue 2, Part D
Real-time ammonia exposure mapping and its link to tracheal mucociliary clearance failure in broilers
Author(s): Gheyath Hadi Ameen, Mansoor Hasan Hassoon, Tharaa Kamel Abadi and Saja Ali Hussein
Abstract: Ammonia (NH₃) is a dominant aerial contaminant in broiler housing and a recognized irritant to the upper respiratory tract, yet exposure assessment on farms is often based on intermittent measurements that underestimate spatial-temporal variability. This study investigated whether real-time ammonia exposure mapping can predict tracheal mucociliary clearance (MCC) impairment in broilers, and whether risk differs between intensive and semi-intensive production systems. Broilers were reared for 42 days in a closed, high-density intensive house and an open-sided, lower-density semi-intensive house. A sensor network continuously logged NH₃ at 1-min intervals across multiple house zones to generate exposure heatmaps and cumulative exposure indices. At day 42, MCC was quantified using an in vivo tracheal marker transit assay, while ex vivo ciliary beat frequency (CBF) was measured by high-speed video microscopy. Tracheal histopathology, goblet cell metrics, and inflammatory gene expression (IL-1β, IL-6, IL-10) were assessed, alongside exploratory profiling of tracheal microbiota. Real-time mapping revealed sustained NH₃ elevation and pronounced spatial gradients in the intensive house, with recurrent peaks and higher cumulative exposure than the semi-intensive system. Intensive-house broilers exhibited significantly prolonged marker transit times and reduced CBF, consistent with functional MCC depression. Histology demonstrated dose-consistent epithelial injury, deciliation, and goblet cell hyperplasia, accompanied by increased IL-1β expression and a shift toward opportunistic bacterial taxa in high-exposure birds. Across individuals, cumulative NH₃ exposure correlated positively with MCC delay and lesion severity and negatively with CBF. These findings indicate that real-time NH₃ mapping can identify high-risk microenvironments within broiler houses and that sustained elevations in NH₃ are mechanistically linked to MCC failure through ciliary dysfunction, mucus dysregulation, and airway inflammation. Continuous NH₃ monitoring integrated with ventilation and litter management is recommended to maintain NH₃ below biologically consequential thresholds and mitigate respiratory compromise in intensive production.
DOI: 10.22271/letters.2025.v5.i2d.162
Pages: 269-278 | Views: 118 | Downloads: 26
Download Full Article: Click Here
How to cite this article:
Gheyath Hadi Ameen, Mansoor Hasan Hassoon, Tharaa Kamel Abadi, Saja Ali Hussein. Real-time ammonia exposure mapping and its link to tracheal mucociliary clearance failure in broilers. Zool Entomol Lett 2025;5(2):269-278. DOI: 10.22271/letters.2025.v5.i2d.162
