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Causes of keel bone damage and their solutions in laying hens

Published online by Cambridge University Press:  04 September 2015

Animal and Poultry Science, University of Guelph, 50 Stone Road E., Guelph, ON, CanadaN1G 2W1
Animal Breeding and Genomics Centre, Wageningen University, PO Box 338, 6700 AHWageningen, The Netherlands
Avian Science Research Centre, SRUC, Auchincruive Campus, Ayr, KA6 5HW, United Kingdom
Field Research Station at Fort Missoula, Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
Research Center for Proper Housing: Poultry and Rabbits (ZTHZ) Division of Animal Welfare, VPH Institute, University of Bern, Burgerweg 22, 3052 Zollikofen, Switzerland
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Keel bone damage (KBD) is a critical issue facing the contemporary laying hen industry due to the likely pain leading to compromised welfare and reduced productivity. Recent reports suggest that KBD, while highly variable and likely dependent on a host of factors, extends to all housing systems (including traditional battery cages, furnished cages and non-cage systems), genetic lines, and management styles. Despite the extent of the problem, the research community remains uncertain as to the causes and influencing factors of KBD. To combat these issues, the current review was produced following discussions from the 1st International Keel Bone Damage Workshop held in Switzerland in April 2014. This exercise sought to assess current knowledge, foster novel collaborations, propose unique methodologies and highlight the key areas where innovative research is needed. The following paper is based on the content of those discussions and presents nine recommendations for future research efforts.

Copyright © World's Poultry Science Association 2015 

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BAIER, D.B., GATESY, S.M. and JENKINS, F.A. (2006) A critical ligamentous mechanism in the evolution of avian flight. Nature 445: 307-310.CrossRefGoogle ScholarPubMed
BAIRD, H.T., EGGETT, D.L. and FULLMER, S. (2008) Varying ratios of omega-6: omega-3 fatty acids on the pre-and postmortem bone mineral density, bone ash, and bone breaking strength of laying chickens. Poultry Science 87: 323-328CrossRefGoogle ScholarPubMed
BESTMAN, M. and WAGENAAR, J.P. (2014) Health and Welfare in Dutch Organic Laying Hens. Animals 4: 374-390.CrossRefGoogle ScholarPubMed
BROOM, D.M. (1991) Animal Welfare: Concepts and measurements. Journal of Animal Science 69: 4167-4175.CrossRefGoogle Scholar
T. CASEY-TROTT, T., HEERKENS, J., PETRIK, M., REGMI, P., SCHRADER, L., TOSCANO, M.J. and WIDOWSKI, T. (in press) Methods for Assessment of Keel Bone Damage in Poultry. Poultry Science: in press.Google Scholar
CHENG, T.K. and COON, C.N. (1990) Effect of calcium source, particle size, limestone solubility in vitro, and calcium intake level on layer bone status and performance. Poultry Science 69: 2214-2219.CrossRefGoogle ScholarPubMed
DIAL, K.P. (2003) Wing-assisted incline running and the evolution of flight. Science 299: 402-404.CrossRefGoogle ScholarPubMed
DIAL, K.P. and JACKSON, B.E. (2011) When hatchlings outperform adults: locomotor development in Australian brush turkeys (Alectura lathami, Galliformes). Proceedings Royal Society Biological Sciences 278: 1610-1616.CrossRefGoogle ScholarPubMed
DIAL, K.P., JACKSON, B.E. and SEGRE, P. (2008) A fundamental avian wing-stroke provides a new perspective on the evolution of flight. Nature 451: 985-989.CrossRefGoogle ScholarPubMed
EGGEN, A. (2012) The development and application of genomic selection as a new breeding paradigm. Animal Frontiers 2: 10-15.CrossRefGoogle Scholar
FAWC (2010) Opinion on Osteoporosis and Bone Fractures in Laying Hens . Farm Animal Welfare Council, London.Google Scholar
FAWC (2013) An open letter to Great Britain Governments: Keel bone fracture in laying hens.Google Scholar
FILIPA, A., BYRNES, R., PATERNN, M.V., MYER, G.D. and HEWETT, T. (2010) Neuromuscular Training Improves Performance on the Star Excursion Balance Test in Young Female Athletes. Journal of Orthopaedic & Sports Physical Therapy 40: 551–558.CrossRefGoogle ScholarPubMed
FLEMING, R.H., MCCORMACK, H.A. and WHITEHEAD, C.C. (1998) Bone structure and strength at different ages in laying hens and effects of dietary particulate limestone, vitamin K and ascorbic acid. British Poultry Science 39: 434-440.CrossRefGoogle ScholarPubMed
FULTON, J.E. (2012) Genomic selection for poultry breeding. Animal Frontiers 2: 30-36.CrossRefGoogle Scholar
GEBHARDT-HENRICH, S. and FRÖLICH, E.K.F. (2012) Auftreten von Brustbeinfrakturen und individuelles Verhalten bei Legehennen, in: ERHARD, M., POLLMAN, U., PUPPE, B., REITER, K. & WAIBLINGER, S. (Eds) KTBL, pp. 52-60 (Freiburg, Germany).Google Scholar
GUINOTTE, F., GAUTRON, J., NYS, Y. and SOURMARMON, A. (1995) Calcium solubilisation and retention in the gastrointestinal tract in chicks (Gallus domesticus) as a function of gastric acid secretion inhibition and of calcium carbonate particle size. British Journal of Nutrition 73: 125-139.CrossRefGoogle ScholarPubMed
GUNNARSSON, S., YNGVESSON, J., KEELING, L.J. and FORKMAN, B. (2000) Rearing without early access to perches impairs the spatial skills of laying hens. Applied Animal Behaviour Science 67: 217-228.CrossRefGoogle ScholarPubMed
HEERKENS, J., DELEZIE, E., KEMPEN, I., ZOONS, J., RODENBURG, T.B. and TUYTENS, F. (2013) Do keel bone deformations affect egg-production in end-of-lay housing hens housed in aviaries?, in: TAUSON, R., BLOKHUIS, H.J., BERG, L. & ELSON, A. (Eds) 9th European Poultry Conference, pp.127 (Uppsala, Sweden).Google Scholar
HEERKENS, J.L.T., KEMPEN, I., ZOONS, J., DELEZIE, E., RODENBURG, T.B., AMPE, B. and TUYTTENS, F.A.M. (2014) Effect of aviary housing characteristics on laying hen welfare and performance. Proceedings of the 48th Congress of the International Society for Applied Ethology, Vitoria-Gasteiz, Spain pp. 158.CrossRefGoogle Scholar
HEERS, A.M. and DIAL, K.P. (2012) From extant to extinct: locomotor ontogeny and the evolution of avian flight. Trends in Ecology and Evolution 27: 296-305.CrossRefGoogle ScholarPubMed
HESTER, P.Y., ENNEKING, S.A., HALEY, B.K., CHENG, H.W., EINSTEIN, M.E. and RUBIN, D.A. (2013) The effect of perch availability during pullet rearing and egg laying on musculoskeletal health of caged White Leghorn hens. Poultry Science 92: 1972-1980.CrossRefGoogle ScholarPubMed
HUTCHINSON, J.R., ANDERSON, F.C., BLEMKER, S.S. and DELP, S.L. (2005) Analysis of hindlimb muscle moment arms in Tyrannosaurus rex using a three-dimensional musculoskeletal computer model: implications for stance, gait, and speed. Paleobiology 31: 676-701.CrossRefGoogle Scholar
HYRE, H.M. (1955) The effect of heredity and environment on keel deformities in White Leghorns. West Virginia Agricultural Experiment Station Bulletin 381.CrossRefGoogle Scholar
JACKSON, B.E. and DIAL, K.P. (2011) Scaling of mechanical power output during burst escape flight in the Corvidae. Journal of Experimental Biology 214: 452-461.CrossRefGoogle ScholarPubMed
KAPPELI, S., GEBHARDT-HENRICH, S.G., FROHLICH, E., PFULG, A. and STOFFEL, M.H. (2011) Prevalence of keel bone deformities in Swiss laying hens. British Poultry Science 52: 531-536.CrossRefGoogle ScholarPubMed
KONDO, K.L. (2008) Osteoporotic vertebral compression fractures and vertebral augmentation. Seminars in interventional radiology. Thieme Medical Publishers pp. 413.CrossRefGoogle Scholar
KOZAK, M., TOBALSKE, B., MARTINS, C., WERBEL, H. and HARLANDER-MATAUSCHEK, A. (2015) Chick- locomotion in a multilayer environment. Accepted in Poultry Science Association 104rd Annual Meeting, Kentucky, USA.Google Scholar
LEBLANC, C., TOBALSKE, B., WUERBEL, H. and HARLANDER-MATAUSCHEK, A. (2015) Locomotion skills of chicks over an inclined walkway. Accepted in Poultry Science Association 104rd Annual Meeting,Kentucky, USA.Google Scholar
LIU, D., VEIT, H.P., WILSON, J.H. and DENBOW, D.M. (2003) Long-term supplementation of various dietary lipids alters bone mineral content, mechanical properties and histological characteristics of Japanese quail. Poultry Science 82: 831-839.CrossRefGoogle ScholarPubMed
LOPEZ, J. (2007) Animal Welfare: Global Issues, Trends and Challenges. Scientific and Technical Review, Vol. 24 (2). Canadian Veterinary Journal 48: 1163-1164.Google Scholar
MOBERG, G.P. (1985) Biological response to stress: Key to assessment of well-being, in: MOBERG, G.P. (Ed) American Physiological Society, pp. 28-49 (Bethesda, MD).Google Scholar
MOINARD, C., STATHAM, P. and GREEN, P.R. (2004a) Control of landing flight by laying hens: implications for the design of extensive housing systems. British Poultry Science 45: 578-584.CrossRefGoogle ScholarPubMed
MOINARD, C., STATHAM, P., HASKELL, M.J., MCCORQUODALE, C., JONES, R.B. and GREEN, P.R. (2004b) Accuracy of laying hens in jumping upwards and downwards between perches in different light environments. Applied Animal Behaviour Science 85: 77-92.CrossRefGoogle Scholar
NASR, M.A.F., MURELL, J. and NICOL, C.J. (2013) The effect of keel fractures on egg production, feed, and water consumption in individual laying hens. British Poultry Science 54: 165-170.CrossRefGoogle ScholarPubMed
NASR, M.A.F., MURELL, J., WILKINGS, L.J. and NICOL, C.J. (2012a) The effect of two classes of opioid drug on the landing ability of laying hens with and without keel fractures, in: UFAW Animal Welfare Conference: Recent Advances in Animal Welfare Science III,York, UK.Google Scholar
NASR, M.A.F., MURELL, J., WILKINGS, L.J. and NICOL, C.J. (2012b) The effect of keel fractures on egg production parameters, mobility and behaviour in individual laying hens. Animal Welfare 21: 127-135.CrossRefGoogle Scholar
NASR, M.A.F., MURELL, J., WILKINGS, L.J. and NICOL, C.J. (2012c) Do Laying Hens with Keel Bone Fractures Experience Pain? PLoS One 7: e42420.CrossRefGoogle ScholarPubMed
NASR, M.A.F., MURELL, J., WILKINGS, L.J. and NICOL, C.J. (2015) The effects of two non-steroidal anti-inflammatory drugs on the mobility of laying hens with keel bone fractures. Veterinary Anaesthesia and Analgesia 42: 197-204.CrossRefGoogle ScholarPubMed
PETRIK, M.T., GUERIN, M.T. and WIDOWSKI, T.M. (2015) On-farm comparison of keel fracture prevalence and other welfare indicators in conventional cage and floor-housed laying hens in Ontario, Canada. Poultry Science 94: 579-585.CrossRefGoogle Scholar
PICKEL, T., SCSHOLZ, B. and SCHRADER, L. (2010) Perch material and diameter affects particular perching behaviours in laying hens. Applied Animal Behaviour Science 127: 37-42.CrossRefGoogle Scholar
PICKEL, T., SCSHOLZ, B. and SCHRADER, L. (2011) Pressure load on keel bone and foot pads in perching laying hens in relation to perch design. Poultry Science 90: 715-24.CrossRefGoogle ScholarPubMed
PRUNIER, A., MOUNIER, L., LE NEINDRE, P., LETERRIER, C., MORMÈDE, P., PAULMIER, V., PRUNET, P., TERLOUW, C. and GUATTEO, R. (2013) Identifying and monitoring pain in farm animals: a review. A nimal 7: 998-1010.Google Scholar
RATH, N.C., HUFF, G.R., HUFF, W.E. and BALOG, J.M. (2000) Factors regulating bone maturity and strength in poultry. Poultry Science 79: 1024-1032.CrossRefGoogle ScholarPubMed
RICHARDS, G.J., BROWN, S.N., BOOTH, F., TOSCANO, M.J. and WILKINS, L.J. (2012) Panic in free-range laying hens. Veterinary Record 170: 519.CrossRefGoogle ScholarPubMed
RODENBURG, T.B., TUYTTENS, F.A.M., DE REU, K., HERMAN, L., ZOONS, J. and SONCK, B. (2008) Welfare assessment of laying hens in furnished cages and non-cage systems: an on-farm comparison. Animal Welfare 17: 363-373.CrossRefGoogle Scholar
SANDILANDS, V., MOINARD, C. and SPARKS, N.H.C. (2009) Providing laying hens with perches: fulfilling behavioural needs but causing injury? British Poultry Science 50: 395-406.CrossRefGoogle ScholarPubMed
SCHOLZ, B., KJAER, J.B. and SRADER, L. (2014) Analysis of landing behaviour of three layer lines on different perch designs. British Poultry Science 55: 419-426.CrossRefGoogle ScholarPubMed
SCHOLZ, B., RÖNCHEN, S., HAMANN, H., HEWICKER-TRAUTWEIN, M. and DISTL, O. (2008) Keel bone condition in laying hens: a histological evaluation of macro scopically assessed keel bones. Berliner und Münchener Tierarztliche Wochenschrift 121: 89-94.Google Scholar
SCOTT, G., LAMBE, N.R. and HITCHCOCK, D. (1997) Ability of laying hens to negotiate horizontal perches at different heights, separated by different angles. British Poultry Science 38: 48-54.CrossRefGoogle ScholarPubMed
STRATMANN, A., FROHLICH, E.K.F., GEBHARDT-HENRICH, S., HARLANDER-MATAUSCHEK, A., WÜRBEL, H. and TOSCANO, M.J. (2015a) Modification of aviary design reduces incidence of falls, collisions and keel bone damage in laying hens. Applied Animal Behaviour Science 165: 112-123.CrossRefGoogle Scholar
STRATMANN, A., TOSCANO, M.J., FROHLICH, E.K.F., HARLANDER-MATAUSCHEK, A. and GEBHARDT-HENRICH, S. (2015b) Do soft perches reduce keel bone fractures in laying hens? PlosONe 10: e0122568.CrossRefGoogle ScholarPubMed
STRATMANN, A., FRÖHLICH, E.K.F., GEBHARDT-HENRICH, S.G., HARLANDER-MATAUSCHEK, A., WÜRBEL, H., TOSCANO, M.J. (in press) Genetic selection to increase bone strength affects prevalence of keel bone damage and egg parameters in laying hens. Poultry Science: in press.Google Scholar
STRATMANN, A., FROHLICH, E., WÜRBEL, H. and GEBHARDT-HENRICH, S.G. (2013) Crashes of laying hens in aviary systems. Proceedings of the Joint Meeting of the 33rd International Ethological Conference (IEC) & the Association for the Study of Animal Behavioir (ASAB) Conference,Newcastle-Gateshead, UK.Google Scholar
TARLTON, J.F., WILKINS, L.J., TOSCANO, M.J., AVERY, N.C. and KNOTT, L. (2013) Reduced bone breakage and increased bone strength in free range laying hens fed omega-3 polyunsaturated fatty acid supplemented diets. Bone 52: 578-586.CrossRefGoogle ScholarPubMed
THIRUVENKADAN, A.K., PANNEERSELVAM, S. and PRABAKARAN, R. (2010) Layer breeding strategies: an overview. World's Poultry Science Journal 66: 477-502.CrossRefGoogle Scholar
TIEMEIER, O.W. (1941) Repaired bone injuries in birds. Auk 58: 350-359.CrossRefGoogle Scholar
TILLMANN, J.E. (2009) Fear of the dark: night-time roosting and anti-predation behaviour in the grey partridge (Perdix perdix L.). Behaviour 146: 999-1023.CrossRefGoogle Scholar
TOBALSKE, B.W. and DIAL, K.P. (2000) Effects of body size on take-off flight performance in the Phasianidae (Aves). Journal of Experimental Biology 203: 3319-3332.CrossRefGoogle ScholarPubMed
TOBALSKE, B.W. and DIAL, K.P. (2007) Aerodynamics of wing-assisted incline running in birds. Journal of Experimental Biology 210: 1742-1751.CrossRefGoogle ScholarPubMed
TOBALSKE, B.W., HEDRICK, T.L., DIAL, K.P. and BIEWENER, A.A. (2003) Comparative power curves in bird flight. Nature 421: 363-366.CrossRefGoogle ScholarPubMed
TOMASZEWSKI, P.K., VERDONSCHOT, N., BULSTRA, S.K. and VERKERKE, G.J. (2010) A comparative finite-element analysis of bone failure and load transfer of osseointegrated prostheses fixations. Annals of Biomedical Engineering 38: 2418-2427.CrossRefGoogle ScholarPubMed
TOSCANO, M.J. (in press) The relationship between keel bone fractures, egg production for laying hens within large groups. Poultry Science Association 104rd Annual Meeting and Kentucky, USA.Google Scholar
TOSCANO, M.J., BOOTH, F., WILKINS, L.J., AVERY, N.C., BROWN, S.B., RICHARDS, G. and TARLTON, J.F. (2015) The effects of long (C20/22) and short (C18) chain omega-3 fatty acids on keel bone fractures, bone biomechanics, behaviour and egg production in free range laying hens. Poultry Science 94: 823-835.CrossRefGoogle ScholarPubMed
TOSCANO, M.J., BOOTH, F., WILKINS, L.J., BROWN, S.B., RICHARDS, G. and TARLTON, J.F. (2014) Use of an impact tester to assess the likelihood of fractures occuring against key bird- and motion-related factors. Proceedings of the 2014 Poultry Science Association Annual Meeting, Corpus Christi.Google Scholar
TOSCANO, M.J., WILKINS, L.J., MILBURN, G., THORPE, K. and TARLTON, J.F. (2013) Development of an ex vivo protocol to model bone fracture in laying hens resulting from collisions. (Witten, P.E., Ed.). PLoS One 8: e66215.CrossRefGoogle Scholar
TOSCANO, M.J., BOOTH, F., WILKINS, L.J., AVERY, N.C., BROWN, S.B., RICHARDS, G., TARLTON, J.F. (in press) The effects of long (C20/22), short (C18) chain omega-3 fatty acids on keel bone fractures, bone biomechanics, behavior and and egg production in free-range laying hens. Poultry Science: in press.Google Scholar
WARREN, D.E. (1937) Physiological and genetic studies of crooked keels in chickens. Kansas Agricultural Experiment Station Technical Bulletin: 44.Google Scholar
WATKINS, B.A., LI, Y., LIPPMAN, H.E. and FENG, S. (2003) Modulatory effect of omega-3 polyunsaturated fatty acids on osteoblast function and bone metabolism. Prostaglandins Leukotrienes Essential Fatty acids 68: 387-398.CrossRefGoogle ScholarPubMed
WHITEHEAD, C.C. (2004a) Skeletal disorders in laying hens: the problem of osteoporosis and bone fractures, in: PERRY, G.C. (Ed.) Welfare of the Laying Hen, pp. 259-270 (Wallingford, CABI Publishing).Google Scholar
WHITEHEAD, C.C. (2004b) Overview of bone biology in the egg-laying hen. Poultry Science 83: 193-199.CrossRefGoogle ScholarPubMed
WHITEHEAD, C.C. and FLEMING, R.H. (2000) Osteoporosis in cage layers. Poultry Science 79: 1033-1041.CrossRefGoogle ScholarPubMed
WILKINS, L.J., BROWN, S.N., ZIMMERMAN, P.H., LEEB, C. and NICOL, C.J. (2004) Investigation of palpation as a method for determining the prevalence of keel and furculum damage in laying hens. Veterinary Record 155: 547-549.CrossRefGoogle ScholarPubMed
WILKINS, L.J., MCKINSTRY, J.L., AVERY, N.C., KNOWLES, T.G., BROWN, S.N., TARLTON, J. and NICOL, C.J. (2011) Influence of housing system and design on bone strength and keel bone fractures in laying hens. Veteterinary Record 169: 414.CrossRefGoogle Scholar