Alexandri, C., Lucaa, L., & Kevorchiana, C. (2015). Subsistence economy and food security: The case of rural households from Romania. Procedia Economics and Finance,22, 672–680.
Article
Google Scholar
Bain, M. M., Nys, Y., & Dunn, I. C. (2016). Increasing persistency in lay and stabilising egg quality in longer laying cycles: What are the challenges? British Poultry Science,57, 330–338.
Article
Google Scholar
Baiphethi, M. N., & Jacobs, P. T. (2009). The contribution of subsistence farming to food security in South Africa. Agrekon,48, 459–482.
Article
Google Scholar
Bal, A. (2012). Novogen makes good progress. Retrieved Feb 14, 2018 from http://www.poultryworld.net/Breeders/General/2012/5/Novogen-makes-good-progress-WP010347W/.
Bennewitz, J., Bögelein, S., Stratz, P., Rodehutscord, M., Piepho, H. P., Kjaer, J. B., et al. (2014). Genetic parameters for feather pecking and aggressive behavior in a large F2-cross of laying hens using generalized linear mixed models. Poultry Science,93(4), 810–817.
Article
Google Scholar
Besbes, B., Tixier-Boichard, M., Hoffmann, I., & Jain, G. L. (2007). Future trends for poultry genetic resources. In Proceedings of the international conference poultry in the twenty-first century: Avian influenza and beyond, At Bangkok, Thailand.
Big Dutchman. (2016). PickPuck permanently occupies the layers and wears down the beak in a natural way. Retrieved March 05, 2018, from https://www.bigdutchman.com/en/egg-production/news/detail/pickpuck-permanently-occupies-the-layers-and-wears-down-the-beak-in-a-natural-way.html.
Bridle, B. W., Julian, R., Shewen, P. E., Vaillancourt, J.-P., & Kaushik, A. K. (2006). T lymphocyte subpopulations diverge in commercially raised chickens. Canadian Journal of Veterinary Research,70, 183–190.
Google Scholar
Brinker, T., Bijma, P., Visscher, J., Rodenburg, T. B., & Ellen, E. D. (2014). Plumage condition in laying hens: genetic parameters for direct and indirect effects in two purebred layer lines. Genetics Selection Evolution,46, 33.
Article
Google Scholar
Candelotto, L., Stratmann, A., Gebhardt-Henrich, S. G., Rufener, C., van de Braak, T., & Toscano, M. J. (2017). Susceptibility of keel bone fracture in laying hens and the role of genetic variation. Poultry Science,96, 3517–3528.
Article
Google Scholar
CodeEFABAR. (2018). Retrieved Feb 04, 2018, from http://www.responsiblebreeding.eu/.
D’Silva, J., & Webster, J. (Eds.). (2010). The meat crisis: Developing more sustainable production and consumption. London: Earthscan.
Google Scholar
Dawkins, M. S. (2008). The science of animal suffering. Ethology,114(10), 937–945.
Article
Google Scholar
Dawkins, M. S. (2016). Animal welfare and efficient farming: Is conflict inevitable? Animal Production Science,52, 201–208.
Google Scholar
De Haas, E. N., Bolhuis, E., de Jong, I. C., Kemp, B., Janczak, A. M., & Rodenburg, T. B. (2014a). Predicting feather damage in laying hens during the laying period. Is it the past or is it the present? Applied Animal Behaviour Science,160, 75–85.
Article
Google Scholar
De Haas, E. N., Bolhuis, J. E., Kemp, B., Groothuis, T. G. G., & Rodenburg, T. B. (2014b). Parents and early life environment affect behavioral development of laying hen chickens. PLoS ONE,9(3), e90577. https://doi.org/10.1371/journal.pone.0090577.
Article
Google Scholar
Ellen, E. D., Rodenburg, T. B., Albers, G. A. A., Bolhuis, J. E., Camerlink, I., Duijvesteijn, N., et al. (2014). The prospects of selection for social genetic effects to improve welfare and productivity in livestock. Frontiers in Genetics,5, 377.
Article
Google Scholar
European Chicken Commitment. (2018). Retrieved Feb 20, 2018, from http://welfarecommitments.com/europeletter/.
FAOSTAT. (2018). Retrieved Feb 20, 2018, from http://www.fao.org/faostat/en/#data/QL.
Fleming, R. H., McCormack, H. A., McTeir, L., & Whitehead, C. C. (2004). Incidence, pathology and prevention of keel bone deformities in the laying hen. British Poultry Science,45, 320–330.
Article
Google Scholar
Fleming, R. H., McCormack, H. A., McTier, L., & Whitehead, C. C. (2006). Relationships between genetic, environmental and nutritional factors influencing osteoporosis in laying hens. British Poultry Science,47, 742–755.
Article
Google Scholar
Fleming, R. H., Whitehead, C. C., Alvey, D., Gregory, N. G., & Wilkins, L. J. (1994). Bone strength and breaking strength in laying hens housed in different husbandry systems. British Poultry Science,35, 651–662.
Article
Google Scholar
Galli, R., Preusse, G., Uckermann, O., Bartels, T., Krautwald-Junghanns, M. E., Koch, E., et al. (2017). In ovo sexing of chicken eggs by fluorescence spectroscopy. Analytical and Bioanalytical Chemistry,409, 1185–1194.
Article
Google Scholar
Garnham, L., & Løvlie, H. (2018). Sophisticated fowl: The complex behaviour and cognitive skills of chickens and red junglefowl. Behavioural Science,8, 13.
Article
Google Scholar
Gebhardt-Henrich, S. G., Pfulg, A., Fröhlich, E. K. F., Käppeli, S., Guggisberg, D., Liesegang, A., et al. (2017). Limited associations between Keel Bone Damage and bone properties measured with computer tomography, three-point bending test, and analysis of minerals in Swiss laying hens. Frontiers in Veterinary Science,4, 128.
Article
Google Scholar
Gremmen, B., Bruijnis, M. R. N., Block, V., & Stassen, E. N. (2018). A public survey on handling male chicks in the Dutch egg sector. Journal of Agricultural and Environmental Ethics,31, 93–107.
Article
Google Scholar
Grumbles, L. C. (1959). Cage layer fatigue (cage paralysis). Avian Diseases,3, 122–125.
Article
Google Scholar
Harlander-Matauschek, A., Rodenburg, T. B., Sandilands, V., Tobalske, B. W., & Toscano, M. J. (2015). Causes of keel bone damage and their solutions in laying hens. World’s Poultry Science Journal,71, 461–472.
Article
Google Scholar
Haynes, R. P. (2008). Animal welfare. Competing conceptions and their ethical implications. Dordrecht: Springer.
Google Scholar
Heerkens, J. L., Delezie, E., Rodenburg, T. B., Kempen, I., Zoons, J., Ampe, B., et al. (2016). Risk factors associated with keel bone and foot pad disorders in laying hens housed in aviary systems. Poultry Science,95, 482–488.
Article
Google Scholar
Hendrix Genetics. (2018). Animal welfare initiatives. Retrieved Feb 14, 2018, from https://www.hendrix-genetics.com/en/hendrix-genetics/sustainability/animal-welfare/.
Hernandez, E., Fawcett, A., Brouwer, E., Rau, J., & Turner, P. V. (2018). Speaking up: Veterinary ethical responsibilities and animal welfare issues in everyday practice. Animals,8, 15.
Article
Google Scholar
Howard, P. H. (2016). Enforcing the new enclosures: Agricultural inputs. In P. H. Howard (Ed.), Concentration and power in the food industry, who controls what we eat? (pp. 104–123). London: Bloomsbury.
Google Scholar
International Egg Commission. (2018a). Annual Review 2018. https://www.internationalegg.com/document_category/publications/.
International Egg Commission. (2018b). The IEC Journal 31. https://www.internationalegg.com/document_category/publications/.
Jaffe, G. (2018). European Union opinion on gene editing: Insightful or missed opportunity? Retrieved February 14, 2018 from https://allianceforscience.cornell.edu/blog/2018/01/european-union-opinion-on-gene-editing-insightful-or-missed-opportunity/.
Joint Animal Protection Statement on the Welfare of Broiler Chickens. (2018). Retrieved Feb 20, 2018, from http://welfarecommitments.com/letter.pdf.
Lambton, S. L., Nicol, C. J., Friel, M., Main, D. C. J., McKinstry, J. L., Sherwin, C. M., Walton, J., & Weeks, C. A. (2013). A bespoke management package can reduce levels of injurious pecking in loose-housed laying hen flocks. Veterinary Record, 172, 423–426.
Article
Google Scholar
Leenstra, F., Munnichs, G., Beekman, V., van den Heuvel-Vromans, E., Aramyan, L., & Woelders, H. (2011). Killing day-old chicks? Public opinion regarding potential alternatives. Animal Welfare,20, 37–45.
Google Scholar
Marino, L. (2017). Thinking chickens: A review of cognition, emotion, and behavior in the domestic chicken. Animal Cognition,20, 127–147.
Article
Google Scholar
Muir, W. M., Cheng, H.-W., & Croney, C. (2014). Methods to address poultry robustness and welfare issues through breeding and associated ethical considerations. Frontiers in Genetics,5, 93–103.
Article
Google Scholar
Muir, W. M., et al. (2008). Genome-wide assessment of worldwide chicken SNP genetic diversity indicates significant absence of rare alleles in commercial breeds. Proceedings of the National Academy of Sciences,105, 17312–17317.
Article
Google Scholar
Mullan, S. M., Szmaragd, C., Wrathall, J. H. M., Cooper, M., Jamieson, J., Bond, A., et al. (2016). Animal welfare initiatives improve feather cover of cage-free laying hens in the UK. Animal Welfare,25, 243–253.
Article
Google Scholar
Nasr, M., Browne, W. J., Caplen, G., Hothersall, B., Murrell, J. C., & Nicol, C. J. (2013). Positive affective state induced by opioid analgesia in laying hens with bone fractures. Applied Animal Behaviour Science,147, 127–131.
Article
Google Scholar
Nasr, M. A. F., Murrell, J., Wilkins, L. J., & Nicol, C. J. (2012). The effects of keel bone fracture on egg production parameters, mobility and behavior in individual laying hens. Animal Welfare,21, 127–135.
Article
Google Scholar
Nicol, C. J. (2015). Genetics and domestication. In The behavioural biology of chickens (pp. 1–14). Croydon: CABI.
Nicol, C. J. (2019). Feather pecking in laying hens, why they do it and welfare implications. In Poultry feathers and skin. CABI.
Nussbaum, M. C. (2004). Beyond ‘compassion and humanity’. Justice for nonhuman animals. In C. R. Sunstein & M. C. Nussbaum (Eds.), Animal rights (pp. 299–320). Oxford: Oxford University Press.
Google Scholar
Nussbaum, M. (2006). Frontiers of justice: Disability, nationality, species membership. Cambridge: Harvard University Press.
Google Scholar
Pettersson, I. C., Weeks, C. C., Wilson, L. R. M., & Nicol, C. J. (2016). Consumer perceptions of free-range laying hen welfare. British Food Journal,118, 1999–2013.
Article
Google Scholar
Preisinger, R. (2017). Innovative layer genetics to handle global challenges in egg production. British Poultry Science,59, 1–6.
Article
Google Scholar
Rauw, W. M., & Gomez-Raya, L. (2014). Genotype by environment interaction and breeding for robustness in livestock. Frontiers in Genetics,6, 310.
Google Scholar
Regan, T. (1983). The case for animal rights. Berkeley: University of California Press.
Google Scholar
Regmi, P., Nelson, N., Steibel, J. P., Anderson, K. E., & Karcher, D. M. (2016). Comparisons of bone properties and keel deformities between strains and housing systems in end-of-lay hens. Poultry Science,95, 2225–2234.
Article
Google Scholar
Riber, A. B., & Hinrichsen, L. K. (2017). Welfare consequences of omitting beak trimming in barn laying hens. Frontiers in Veterinary Science,4, 222.
Article
Google Scholar
RSPCA. (2011). Domestic fowl: Good practice for housing and care. Horsham: RSPCA.
Google Scholar
RSPCA. (2017a). RSPCA response to genomics and genome-editing inquiry. Retrieved March 01, 2018, from http://data.parliament.uk/writtenevidence/committeeevidence.svc/evidencedocument/science-and-technology-committee/genomics-and-genomeediting/written/46331.html.
RSPCA. (2017b). RSPCA welfare standards for meat chickens. Retrieved Feb 04, 2018, from https://science.rspca.org.uk/sciencegroup/farmanimals/standards/chickens.
Rufener, C., Baur, S., Stratmann, A., & Toscano, M. J. (2018). Keel bone fractures affect egg laying performance but not egg quality in laying hens housed in a commercial aviary system. Poultry Science,98, 1589–1600. https://doi.org/10.3382/ps/pey544.
Article
Google Scholar
Sandilands, V., Moinard, C., & Sparks, N. H. C. (2009). Providing laying hens with perches: Fulfilling behavioural needs but causing injury? British Poultry Science,50, 395–406.
Article
Google Scholar
Sariozkan, S., Kara, K., & Güçlü, B. K. (2016). Applicability of non-feed removal programs to induce molting instead of the conventional feed withdrawal method in brown laying hens. Revista Brasileira de Ciência Avícola,18, 535–541.
Article
Google Scholar
Sherwin, C. M., Richards, G. J., & Nicol, C. J. (2010). Comparison of the welfare of layer hens in 4 housing systems in the UK. British Poultry Science,51, 488–499.
Article
Google Scholar
Singer, P. (2002 [1975]). Animal liberation. New York: Random House Inc.
Smulders, T. V. (2017). The avian hippocampal formation and the stress response. Brain, Behavior and Evolution,90(1), 81–91.
Article
Google Scholar
Springmann, M., et al. (2018). Options for keeping the food system within environmental limits. Nature,562, 519–525.
Article
Google Scholar
Stratmann, A., Fröhlich, E. K., Gebhardt-Henrich, S. G., Harlander-Matauschek, A., Würbel, H., & Toscano, M. J. (2015). Modification of aviary design reduces incidence of falls, collisions and keel bone damage in laying hens. Applied Animal Behaviour Science,165, 112–123.
Article
Google Scholar
Stratmann, A., Fröhlich, E. K., Gebhardt-Henrich, S. G., Harlander-Matauschek, A., Würbel, H., & Toscano, M. J. (2016). Genetic selection to increase bone strength affects prevalence of keel bone damage and egg parameters in commercially housed laying hens. Poultry Science,5, 975–984.
Article
Google Scholar
Su, G., Kjaer, J. B., & Sørensen, P. (2005). Variance components and selection response for feather-pecking behavior in laying hens. Poultry Science,84, 14–21.
Article
Google Scholar
Tao, S. (2012). Trends in China’s poultry breeder grandparent stock. Retrieved Jan 29, 2019, from http://www.efeedlink.com/contents/06-08-2012/92bca385-ce77-4be5-9750-0c22ee18fda8-0143.html.
Tarlton, J. F., Wilkins, L. J., Toscano, M. J., Avery, N. C., & 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.
Article
Google Scholar
The Poultry Site. (2007). Researcher delves into why naturally blind chickens perform better. Retrieved Feb 05, 2018, from http://www.thepoultrysite.com/poultrynews/12329/researcher-delves-into-why-naturally-blind-chickens-perform-better/.
Toscano, M. J. (2018). Skeletal problems in contemporary commercial laying hens. In J. A. Mench (Ed.), Advances in poultry welfare science (1st ed., pp. 151–174). Cambridge: Woodhead Publishing.
Chapter
Google Scholar
Toscano, M. J., Booth, F., Wilkins, L. J., Avery, N. C., Brown, S. B., Richards, G., et al. (2015). The effects of long (C20/22) and short (C18) chain omega-3 fatty acids on keel bone fractures, bone biomechanics, behavior, and egg production in free-range laying hens. Poultry Science,94, 823–835.
Article
Google Scholar
Uitdehaag, K. A., Komen, H., Rodenburg, T. B., Kemp, B., & van Arendonk, J. A. M. (2008). The novel object test as predictor of feather damage in cage-housed Rhode Island Red and White Leghorn laying hens. Applied Animal Behaviour Science,109, 292–305.
Article
Google Scholar
Warren, D. C. (1937). Physiological and genetic studies of crooked keels in chickens. Kansas State College of Agriculture, Technical Bulletin 44. Retrieved Dec 20, 2018, from https://www.ksre.k-state.edu/historicpublications/pubs/STB044.PDF.
Weeks, C. A., Lambton, S. L., & Williams, A. G. (2016). Implications for welfare, productivity and sustainability of the variation in reported levels of mortality for laying hen flocks kept in different housing systems: A meta-analysis of ten studies. PLoS ONE,11(1), e0146394.
Article
Google Scholar
Weeks, C. A., Newton, J., McKinstry, J. L., Friel, M., Walton, J., Edge, S., Main, D. C. J., Nicol, C. J., & Sherwin, C. M. (2011). Predicting the economic costs and benefits of changes aimed at reducing levels of injurious pecking on free-range layer farms. In Poster presentation: UFAW International Symposium, Portsmouth 28-29 June 2011: Making animal welfare improvements: economic and other incentives and constraints.
Weissmann, A., Reitemeier, S., Hahn, A., Gottschalk, J., & Einspanier, A. (2013). Sexing domestic chicken before hatch: A new method for in ovo gender identification. Theriogenoloy,80, 199–205.
Article
Google Scholar
Wilkins, L. J., McKinstry, J. L., Avery, N. C., Knowles, T. G., Brown, S. N., Tarlton, J., et al. (2011). Influence of housing system and design on bone strength and keel bone fractures in laying hens. Veterinary Record,169, 414.
Article
Google Scholar
Willett, W. et al. (2019). Food in the Anthropocene: The EAT–Lancet Commission on healthy diets from sustainable food systems. Retrieved Feb 17, 2019, from https://eatforum.org/content/uploads/2019/01/EAT-Lancet_Commission_Summary_Report.pdf.
Windhorst, H.-W. (2019). Patterns and dynamics of China’s egg industry. Retrieved Feb 17, 2019, from https://zootecnicainternational.com/focus-on/patterns-dynamics-chinas-egg-industry/.
World Health Organization. (2007). Protein and amino acid requirements in human nutrition. In: Report of a joint WHO/FAO/UNU, expert consultation. Technical report series no 935. Geneva: WHO.