|Cheng, Heng Wei|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 11/15/2004
Publication Date: 12/3/2004
Citation: Muir, W.M., Cheng, H. 2004. Breeding for productivity and welfare of laying hens. In: Perry, G., editor. Welfare of the Laying Hen. Cambridge, MA: CABI Publishing. p. 123-138.
Technical Abstract: Genes and genetic-environmental interactions determine the functions of the physiological systems that control animal coping strategies, productivity, and survivability. Genetic selection becomes an important management tool for improving animal coping capability to the intensified farm animal industry and increasing economic benefits. However, over the past five decades in most selection breeding programs only traits directly related to productivity are considered, as a result those breeding programs ignore traits that impact animal welfare. For instance, selective breeding in chickens based on production could affect other genes or systems that are associated with behavioral and physiological characteristics unique to the line in response to stimulations. Recently, a selection program termed 'group selection' has been introduced (Muir and Craig, 1996). The advances of the program allow selection on production traits but takes into account competitive interactions. The method has been verified in poultry breeding applications and has resulted in dramatic improvements in livability, productivity, and welfare. This review represents a summary of current studies of the cellular mechanisms of the selection program and potential strategies for improvement of well-being.