title: Soft perches in an aviary system reduce incidence of keel bone damage in laying hens.
abstract: Keel bone fractures and deviations are one of the major welfare and health issues in commercial laying hens. In non-cage housing systems like aviaries, falls and collisions with perches and other parts of the housing system are assumed to be one of the main causes for the high incidence of keel bone damage. The objectives of this study were to investigate the effectiveness of a soft perch material to reduce keel bone fractures and deviations in white (Dekalb White) and brown laying hens (ISA Brown) kept in an aviary system under commercial conditions. In half of 20 pens, all hard, metal perches were covered with a soft polyurethane material. Palpation of 20 hens per pen was conducted at 18, 21, 23, 30, 38, 44 and 64 weeks of age. Production data including egg laying rate, floor eggs, mortality and feed consumption were collected over the whole laying period. Feather condition and body mass was assessed twice per laying period. The results revealed that pens with soft perches had a reduced number of keel bone fractures and deviations. Also, an interaction between hybrid and age indicated that the ISA hybrid had more fractured keel bones and fewer non-damaged keel bones compared with the DW hybrid at 18 weeks of age, a response that was reversed at the end of the experiment. This is the first study providing evidence for the effectiveness of a soft perch material within a commercial setting. Due to its compressible material soft perches are likely to absorb kinetic energy occurring during collisions and increase the spread of pressure on the keel bone during perching, providing a mechanism to reduce keel bone fractures and deviations, respectively. In combination with genetic selection for more resilient bones and new housing design, perch material is a promising tool to reduce keel bone damage in commercial systems.
authors: Research Center for Proper Housing: Poultry and Rabbits (ZTHZ), Division of Animal Welfare, University of Bern, Bern, Switzerland.
authors: Ariane
authors: A
authors: Stratmann
authors: Research Center for Proper Housing: Poultry and Rabbits (ZTHZ), Federal Food Safety and Veterinary Office, Bern, Switzerland.
authors: Ernst K F
authors: EK
authors: Fröhlich
authors: Animal and Poultry Science, University of Guelph, Guelph, Ontario, Canada N1G2W1.
authors: Alexandra
authors: A
authors: Harlander-Matauschek
authors: Institute of Animal Welfare and Animal Husbandry, Friedrich-Loeffler-Institut, Celle, Germany.
authors: Lars
authors: L
authors: Schrader
authors: Research Center for Proper Housing: Poultry and Rabbits (ZTHZ), Division of Animal Welfare, University of Bern, Bern, Switzerland.
authors: Michael J
authors: MJ
authors: Toscano
authors: Research Center for Proper Housing: Poultry and Rabbits (ZTHZ), Division of Animal Welfare, University of Bern, Bern, Switzerland.
authors: Hanno
authors: H
authors: Würbel
authors: Research Center for Proper Housing: Poultry and Rabbits (ZTHZ), Division of Animal Welfare, University of Bern, Bern, Switzerland.
authors: Sabine G
authors: SG
authors: Gebhardt-Henrich
mesh_terms: D000827:Animal Welfare; D000818:Animals; D002645:Chickens; D050723:Fractures, Bone / Q000175:diagnosis; D006799:Housing, Animal