This collection features four peer-reviewed literature reviews on bone health in poultry. The first chapter reviews the literature on genetic mapping of skeletal traits in both broilers and layers, including both the genetics of skeletal defects and bone quality. As the chapter shows, linkage mapping and genome-wide association studies have identified promising candidate genes with potential for breeding more robust birds. The second chapter focuses on bacterial chondronecrosis with osteomyelitis (BCO), one of the most common causes of lameness in broilers. The chapter summarizes the pathogenesis of BCO and reviews the efficacy of probiotics as a prophylactic treatment. The third chapter discusses bone health in laying hens. It reviews bone development, keel and other bone health problems and factors contributing to poor bone health. It also summarises key strategies for improving bone health, including breeding, nutrition, rearing practices and housing. The final chapter assesses the problem of lameness in intensively-reared broiler flocks. The chapter also discusses skin health in broilers. It summarises key risk factors as well as ways of monitoring and reducing the problem, from breeding programmes and enrichment to sequential feeding regimes.

This collection features five peer-reviewed reviews on ensuring the welfare of laying hens. The first chapter highlights the key welfare issues in poultry housing and management, focussing on the use of conventional cages to house laying hens. The chapter then explores the emergence of enriched cages and cage-free housing, as well as the benefits and risks of each system on bird health and welfare. The second chapter reviews the range of welfare issues affecting free range laying hens. The chapter also highlights the need to improve current understanding of how laying hens behave in free range systems to be able to adequately meet their health and welfare needs. The third chapter discusses the use of beak trimming methods, as well as the welfare concerns that arise as a result of their use. The chapter highlights alternative strategies to reduce the need for these practices which are known to incur acute pain. The fourth chapter reviews the impact of housing and management systems on the skeletal and cognitive development of laying hens. It discusses how nutrition and housing can be optimised to reduce the occurrence of bone health issues. The final chapter reviews current research on the genetics of behavioural traits in poultry, focussing on how breeding can be optimised to reduce aggressive behaviour in laying hens.