An experiment in 630 broilers compared the duration and age of cyclic heat-stress exposure and recovery after return to thermoneutral conditions, measuring growth, mortality, stress markers and heart–lung histopathology.
Key findings
- Heat raised cloacal temperature by at least 1.5°C at all ages. Birds first exposed at day 36 had 67% mortality, continuously heat-exposed birds finished 40.1% lighter than controls, and recovery groups resumed control-like growth rates without compensatory gain. Brief late exposure sharply increased corticosterone and protein carbonyls.
Why this matters globally
The results highlight heat-wave risks to poultry welfare and production, supporting warning systems, ventilation, cooling and contingency plans that protect market-age birds with limited acclimatisation time.
Thai researcher contribution
S. Khempaka of Suranaree University of Technology contributed Thai poultry-production expertise to a globally relevant climate-stress question.
Limitations to consider
This used one broiler strain and specific housing; open-sided and controlled barns may differ beyond temperature. The 67% mortality belongs to one treatment and is not a universal rate. Histology was descriptive, and mitigation efficacy and economics were not tested.