Role of feed additives in mitigating the impact of heat stress on poultry gut health and productivity

As global poultry production expands to meet rising demand, the susceptibility of birds to heat stress has increased owing to advancements in chicken genetics and global warming. This review explores the significant impact of heat stress on poultry gut health by altered gut permeability and microbiota. Heat stress is characterised by prolonged exposure to elevated ambient temperatures, triggering thermoregulatory processes in poultry, which can lead to adverse effects such as respiratory alkalosis and bone degeneration. These physiological disruptions compromise homoeostasis, suppress intestinal immunity and digestive functions and cause gastrointestinal inflammation, thereby affecting the growth, productivity and overall well-being of poultry. Various strategies, including housing modifications, genetic selection, food manipulation and the use of feed additives, such as bioactive chemicals, prebiotics, organic acids, medicinal plants and probiotics, have been employed to mitigate these effects. This review emphasises the role of feed additives in supporting poultry gut health, thereby enhancing animal welfare, productivity and sustainability in the face of climate change. Future research avenues are suggested to improve our understanding and development of effective nutritional strategies to combat heat stress in poultry.