Pathologic changes in end-of-lay hens with regards to different housing systems.

Gross pathologic and histologic changes were investigated in a total of 100 0 end-of-lay hens. Thirty animals were drawn from free range stocks, 270 fr om deep litter stocks, and 700 from caging systems. The following changes were evaluated with regards to housing sytems: Pododermatitis, deformation of the keel bone and amputated beaks occurred p rimarily in free range hens, Deep litter hens also suffered from pododermatitis, keel bone deformation a nd amputated beaks in addition to pecking wounds. In caged hens severe fatty liver syndromes, injuries of the claws and infla mmation of the feather follicles were mainly found. Furthermore, injuries a nd fractures due to handling and transport were almost exclusively found in caged hens. It has to be concluded that ail of the investigated housing systems can pre disposed hens to certain lesions. The documented changes e.g. chronic infla mmation, skelettal deformities and injuries - are painful and may lead to p ermanent alterations. Therefore, these changes should be condemned as confl icting with animal protection regulations.