Beating the Heat: Mitigating Heat Stress in Poultry During Summer

Heat stress has emerged as a serious challenge in poultry production, particularly when the global temperatures continue to rise and extreme heat events have become more frequent. Commercial broilers and layers are especially susceptible to elevated temperatures due to their feather coverage and inability to sweat, thus making their thermoregulation difficult under high ambient conditions. When environmental temperatures surpass the birds’ thermoneutral zone of 18–21°C, particularly above 25°C, chickens begin to exhibit signs of heat stress, such as panting, wing spreading, decreased feed intake, and lethargy. Prolonged exposure to heat stress adversely affects physiological functions, leading to oxidative stress, acid-base imbalance, suppressed immune responses, and ultimately increased mortality rates. These physiological disruptions significantly impair productivity, resulting in reduced feed efficiency, body weight gain, egg production, and overall meat and egg quality. A range of strategies have been developed to mitigate the effects of heat stress in poultry, which include environmental modifications, nutritional interventions, welfare and behavioural management, as well as genetic selection, as detailed in this article.