Impact of Heat Stress on Chicken Performance, Welfare, and Probable Mitigation Strategies

The poultry industry globally provides chicken meat and eggs, the most significant protein sources among animal foods. The industry is grappling with the effect of climate change which causes heat stress and harms the performance and welfare of the chicken. Heat stress has been the most significant environmental stress challenging the global poultry industry, as chickens only tolerate a narrow range of temperatures during heat stress. This review aims to assess the impact of heat stress on chicken performance, welfare, and probable mitigation strategies to ameliorate its hazard. The study reviewed research papers of different authors and revealed that heat stress affects the chicken's performance, nutrition, and health. Heat stress reduces feed efficiency, body weight, feed intake, and egg production, as well as an increase chicken mortality. Some mitigation strategies farmers have employed include modifying the environment by providing adequate ventilation and cooling systems and adjusting their nutrition to help lower the body's metabolic heat output and keep electrolyte levels stable under high-stress, high-temperature circumstances. Therefore, there is a pressing need to study the extent of the resilience of native chicken breeds to the effects of climate change. Moreover, it is necessary to develop newer varieties of chicken, especially heat-tolerant breed lines, in response to climate change and the diverse need of the farmers and consumers.