Probiotics/prebiotics effect on chicken gut microbiota and immunity in relation to heat-stress and climate-change mitigation.

Heat stress is a serious hazard that threatens world poultry production. The avian gut microbiome plays a critical role in improving nutrient utilization, competing with pathogens, stimulating an immune response, and reducing inflammatory reactions. Hence, the gut microbiome has a positive impact on the host's health which appears in the shape of improved body weight, feed conversion rate, and increased birds' productivity (meat or eggs). Accordingly, this review shed light on the chicken gut microbiome, its correlation with the immunity of chicken, and how this affects the general health condition of the bird as well as, the role of prebiotics and probiotics in improving the gut health and increasing birds' productivity, especially under climate change and heat stress condition. The review aims to focus on the significance of maintaining healthy chickens in order to increase the production of poultry meat to satisfy human needs. A robust microbiota and a well-functioning immune system synergistically contribute to the optimal health and productivity of chickens.