Lessons from selection experiments on immune response in the chicken

A multifaceted approach is required to maintain good health in poultry. The comprehensive program includes biosecurity, good management, appropriate v accine and pharmaceutical treatment, and genetic resistance to disease. Bec ause of the myriad of potential pathogens that could exist in a bird's envi ronment, direct selection for each individual pathogen response is not feas ible. Instead, general enhancement of immune response capacity is used as a genetic approach to develop populations that are robust in the face of num erous and varied environmental challenges, Several research groups have con ducted genetic selection experiments on immune response in the chicken, Thi s paper reviews the various approaches that may be taken to selection for i mmune response, gives three in-depth examples that represent different sele ction types, and proposes lessons that may be learned from experimental stu dies to date.