The study will be conducted in commercial-scale buildings of three types:

  • conventional cage housing, the type of housing currently used by the majority of U.S. egg producers;
  • enriched cage housing (also known as a furnished colony system), which provides more freedom of movement because the cages are larger than conventional cages and is also equipped with perches, nesting areas, and material designed to facilitate foraging and dust-bathing behavior; and
  • cage-free aviary, a non-cage system that allows the hens to roam within a section of a building at floor level and vertically to perches and nest boxes.

Mench and Swanson are the co-scientific directors for the study. Darrin Karcher of Michigan State University is the overall project coordinator. Additional cooperating research institutions include Iowa State University and the USDA Agricultural Research Service.

The first research flock was established in late April 2011. The study will be replicated over two flocks with study completion expected in 2014. For updates on the CSES research, please visit