Modification of animals versus modification of the production environment to meet welfare needs.

The balance between genetic modification and welfare may be as old as the chicken and egg debate. Meeting welfare needs of farm animals has become an integral part of animal agriculture. Until recently, environmental and management modifications have been the methods of choice for meeting welfare needs of animals. Genetic selection has improved growth, livability, and general welfare, but some aspects of welfare like metabolic disorders, susceptibility to some diseases, and skeletal problems have increased. Genetic variability in behavioral and physiological traits relating to welfare exists thus raising the possibility of selecting for welfare-related traits. Advances in molecular biology have also made it possible for the identification of QTL for behavioral and welfare traits. Identification of causal or associative genes for welfare traits and improved biotechnology tools raises the possibility of either selecting for improved welfare or genetically modifying birds to suit the commercial production environment. An integration of management, genetics, and genomic tools should be employed to genetically improve production and welfare traits with concurrent welfare risk assessments to address public and consumer concerns.