Informal Nutrition Symposium Immunity lessons and actions: Practical implications1

Nutritional approaches can be used to improve disease resistance while mitigating the nega-tive impact of immunity on bird performance. Supplying dietary nutrients at the appropriate times and amounts is critical for the development, maintenance, and function of the immune system. The immune system consists of multiple tissues and cell types, and when combined with the diversity of pathogens and routes of infection, the complexity of assigning nutrient requirements for immunity becomes apparent. Activation of the immune system reduces bird performance because of decreased food intake and changes in nutrient metabolism. Under-standing the purpose of altered nutrient metabolism may help researchers develop nutritional strategies that complement, or support, the purpose of these catabolic responses to infection. Consequently, providing nutritional support to the immune system during times of critical need may help to mitigate the overall catabolic response to infection. To do so, the proper tools are needed for assessment and understanding of the desired responses from the immune system to particular pathogens. The immune system is dynamic and complex and requires proper care and feeding. Key words: immunity, infection, metabolis