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Thermoregulation and Physiological Responses to Heat Stress in Poultry: A Comprehensive Review
Abstract
Heat stress represents a major constraint in poultry production, adversely affecting bird health, productivity and welfare. This review examines the physiological and biochemical consequences of heat stress in poultry, with particular emphasis on its effects on feed intake, egg production and immune competence. It outlines the principal thermoregulatory mechanisms, including conduction, convection, radiation and evaporative heat loss, through which birds maintain thermal homeostasis. In addition, the roles of stress-associated hormones and metabolic adaptations under elevated ambient temperatures are discussed. Collectively, these physiological alterations lead to reductions in feed intake, growth rate, eggshell formation, egg quality and overall performance, while prolonged exposure may result in increased mortality. The evidence reviewed indicates that heat stress constitutes a multifactorial disturbance, involving coordinated disruptions across metabolic, endocrine, immune and behavioural systems.
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Heat stress, immune function, physiological response, poultry welfare, thermoregulationArticle Metrics
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Copyright (c) 2026 Vanlalhmangaihsanga, Nanda Kumar Roy, Venus Das, V. Keerthi, N.K. Praharaj, Abhijeet Champati
This work is licensed under a Creative Commons Attribution 4.0 International License.
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.
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Vanlalhmangaihsanga, Roy, N. K., Das, V., Keerthi, V., Praharaj, N., & Champati, A. (2026). Thermoregulation and Physiological Responses to Heat Stress in Poultry: A Comprehensive Review. International Journal of Poultry Science, 25, 87–98. https://doi.org/10.66920/ijps.2026.87.98
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