Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-24T11:55:45.512Z Has data issue: false hasContentIssue false

International approaches to the welfare of meat chickens

Published online by Cambridge University Press:  20 June 2011

A. ROBINS
Affiliation:
Centre for Animal Welfare and Ethics, School of Veterinary Science, University of Queensland, Australia
C.J.C. PHILLIPS*
Affiliation:
Centre for Animal Welfare and Ethics, School of Veterinary Science, University of Queensland, Australia
*
Corresponding author: c.phillips@uq.edu.au
Get access

Abstract

Welfare issues and approaches are compared in the following review, for all major meat chicken producing countries. In certain countries, such as the United States and Australia, the industry comprises a small number of integrated, self-regulated companies, whereas in Europe the industry is more diverse, with greater competition, and more government regulation. There is much more meat chicken welfare research and regulation in Europe, and in particular the United Kingdom, than in countries with self-regulated industries, such as the United States, even taking into account the level of meat chicken production in the relevant areas. By contrast, welfare regulation in two of the world's major meat chicken producing countries; namely Brazil and China, is negligible. Some welfare issues are regional, such as high temperatures which are particularly problematic for free range birds, breeds selected for rapid growth and when birds are removed from fully-housed systems. However, similar welfare issues affect intensively-housed birds worldwide, which comprise the majority of animals produced. These include rapid growth rates, predisposing birds to heart and leg problems, especially ascites and sudden death syndrome, and high stocking densities, which inhibit locomotion and environmental exploration, predisposing birds to contact dermatitis. Welfare research in Europe has shown that highly stocked birds spend longer sleeping, congregate around feeders and are more fearful, as well as experiencing higher ammonia levels, which irritate their eyes and respiratory systems. The review concludes that intensive systems present similar welfare issues worldwide; however, European research is more directed to the behavioural and cognitive requirements of the birds, than in self-regulated countries. This will enable their industry to respond better to future welfare requirements from consumers.

Type
Review Article
Copyright
Copyright © World's Poultry Science Association 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

ABEYESINGHE, S.M., NICOL, C.J., HARTNELL, S.J. and WATHES, C.M. (2005) Can domestic fowl, Gallus gallus domesticus, show self-control? Animal Behaviour 70: 111.CrossRefGoogle Scholar
ALI, A.S., LAWSON, M.A., TAUSON, A.H., JENSEN, J.F. and CHWALIBOG, A. (2007) Influence of electrical stunning voltages on bleed out and carcass quality in slaughtered broiler chickens. Archiv fur Geflukelkunde 71: 35-40.Google Scholar
ALVINO, G.M., ARCHER, G.S. and MENCH, J.A. (2009) Behavioural time budgets of broiler chickens reared in varying light intensities. Applied Animal Behaviour Science 118: 54-61.CrossRefGoogle Scholar
ANDREWS, S.M., OMED, H.M. and PHILLIPS, C.J. (1997) The effect of a single or repeated period of high stocking density on the behavior and response to stimuli in meat chicken chickens. Poultry Science 76: 1655-1660.CrossRefGoogle ScholarPubMed
ANON, (undated) Poultry Welfare Research in Canada. Canadian Poultry Research Council, Agriculture, Agri-Food Canada. Accessed 20 June and 2010. http://www.cp-rc.ca/reports/Research_Funding_rpt.pdf; http://www.cp-rc.ca/research_programs/poultry_welfare.html.Google Scholar
ANON, (2010) Poultry Hub, a Poultry CRC Initiative. Research http://www.poultryhub.org/index.php/Research/. Accessed 13 July, 2010.Google Scholar
ARNOULD, C., BIZERAY, D., FAURE, J.M. and LETERRIER, C. (2004) Effects of the addition of sand and string to pens on use of space, activity, tarsal angulations and bone composition in broiler chickens. Animal Welfare 13: 87-94.CrossRefGoogle Scholar
ARNOULD, C. and FAURE, J.M. (2004) Behavioural time budgets of broiler chickens reared in varying light intensities. Applied Animal Behaviour Science 87: 155-170.CrossRefGoogle Scholar
AUSTRALIAN CHICKEN MEAT FEDERATION (ACMF), (2009a) Growing Meat Chickens : ACMF. from http://www.chicken.org.au/page.php?id=6 Last accessed 09/09.Google Scholar
AUSTRALIAN CHICKEN MEAT FEDERATION (ACMF), (2009b) Industry Facts and Figures (IFF, 2009): ACMF. from http://www.chicken.org.au/page.php?id=4. Last accessed 09/09.Google Scholar
BAGHBANZADEH, A. and DECUYPERE, E. (2008) Ascites syndrome in broilers: physiological and nutritional perspectives. Avian Pathology: Journal of the W.V.P.A. 37: 117-126.CrossRefGoogle ScholarPubMed
BAGSHAW, C.S., MATTHEWS, L.R. and ROGERS, A. (2006) Key indicators of poultry welfare in New Zealand. Unpublished client report to MAF policy.Google Scholar
BARNETT, J.L. and GLATZ, P.C. (2004) Developing and implementing a welfare audit in the Australian chicken meat industry, in: Weeks, C.A. & Butterworth, A. (Eds) Measuring and auditing broiler welfare, 231240 (Wallingford, CABI Publishing).CrossRefGoogle Scholar
BERRI, C., DEBUT, M., SANTÉ-LHOUTELLIER, V., ARNOULD, C., BOUTTEN, B., SELLIER, N., BAÉZA, E., JEHL, N., JÉGO, Y., DUCLOS, M.J. and LE BIHAN-DUVAL, E. (2005) Variations in chicken breast meat quality: implications of struggle and muscle glycogen content at death. British Poultry Science 46: 572-579.CrossRefGoogle ScholarPubMed
BESSEI, W. (2006) Welfare of Broilers: A Review. World's Poultry Science Journal 62: 455-466.CrossRefGoogle Scholar
BIZERAY, D., LETERRIER, C., CONSTANTIN, P., PICARD, M. and FAURE, J.M. (2002a) Sequential feeding can increase activity and improve gait score in meat-type chickens. Poultry Science 81: 1798-1806.CrossRefGoogle ScholarPubMed
BIZERAY, D., ESTEVEZ, I., LETERRIER, C. and FAURE, J.M. (2002b) Effects of increasing environmental complexity on the physical activity of broiler chickens. Applied Animal Behaviour Science 79: 27-41.CrossRefGoogle Scholar
BLOKHUIS, H.J. (1983) The relevance of sleep in poultry. World's Poultry Science Journal 39: 33-37.CrossRefGoogle Scholar
BOKKERS, E.A. and KOENE, P. (2003) Behaviour of fast- and slow growing broilers to 12 weeks of age and the physical consequences. Applied Animal Behaviour Science 81: 59-72.CrossRefGoogle Scholar
BRENNAN, C.P., HENDRICKS, G.L., EL-SHEIKH, T.M. and MASHALY, M.M. (2002) Melatonin and the enhancement of immune responses in immature male chickens. Poultry Science 81: 371-375.CrossRefGoogle ScholarPubMed
BROOM, D.M. and FRASER, A.F. (2007) Domestic Animal Behaviour and Welfare (4th Ed), pp. 297 (Wallingford, CABI Publishing).CrossRefGoogle Scholar
BROWN, S.N., NUTE, G.R., BAKER, A., HUGHES, S.I. and WARRISS, P.D. (2008) Aspects of meat and eating quality of broiler chickens reared under standard, maize-fed, free-range or organic systems. British Poultry Science 49: 118-124.CrossRefGoogle ScholarPubMed
BUIJS, S., KEELING, L., RETTENBACHER, S., VAN POUCKE, E. and TUYTTENS, F.A. (2009) Stocking density effects on broiler welfare: Identifying sensitive ranges for different indicators. Poultry Science 88: 1536-1543.CrossRefGoogle ScholarPubMed
CANGAR, O., AERTS, J.M., VRANKEN, E. and BERCKMANS, D. (2008) Effects of different target trajectories on the broiler performance in growth control. Poultry Science 87: 2196-2207.CrossRefGoogle ScholarPubMed
CARRÉ, B., MIGNON-GRASTEAU, S., PÉRON, A., JUIN, H. and BASTIANELLI, D. (2007) Wheat value: Improvements by feed technology, plant breeding and animal genetics. World's Poultry Science Journal 63: 585-596.CrossRefGoogle Scholar
CERIT, H. and AVANUS, K. (2007) Sex identification in avian species using DNA typing methods. World's Poultry Science Journal 63: 91-99.CrossRefGoogle Scholar
CERRATE, S., WANG, Z., COTO, C., YAN, F. and WALDROUP, P.W. (2007) Choice feeding as a means of identifying differences in nutritional needs of broiler strains differing in performance characteristics. International Journal of Poultry Science 6: 713-724.CrossRefGoogle Scholar
CLASSEN, H.L., RIDDELL, C., CERIT, H. and AVANUS, K. (1990) Early growth rate and lighting effects on broiler skeletal disease. Poultry Science 69(Suppl 1): 35.Google Scholar
CORNETTO, T. and ESTEVEZ, I. (2001) Influence of vertical panels on use of space by domestic fowl. Applied Animal Behaviour Science 71: 141-153.CrossRefGoogle ScholarPubMed
DAWKINS, M.S., COOK, P.A., WHITTINGHAM, M.J., MANSELL, K.A. and HARPER, A.E. (2003) What makes free-range broiler chickens range? In situ measurement of habitat preference. Animal Behaviour 66: 151-160.CrossRefGoogle Scholar
DAWKINS, M.S., DONNELLY, C.A. and JONES, T.A. (2004) Chicken welfare is influenced more by housing conditions than by stocking density. Nature 427(6972): 342-344.CrossRefGoogle ScholarPubMed
DAWSON, M.D., BENSON, E.R., MALONE, G.W., ALPHIN, R.L., ESTEVEZ, I. and VAN WICKLEN G.L., (2006) Evaluation of foam-based mass depopulation methodology for floor-reared meat-type poultry operations. Applied Engineering in Agriculture 22: 787-793.CrossRefGoogle Scholar
DE GRAFT-HANSON, J. (2003) Hazard Analysis Critical Control Point System and its Impact on the Meat and Poultry Industry. Avian and Poultry Biology Reviews 14: 79-97.CrossRefGoogle Scholar
DELEZIE, E., LIPS, D., LIPS, R. and DECUYPERE, E. (2006) Is the mechanisation of catching meat chickens a welfare improvement? Animal Welfare 15: 141-147.CrossRefGoogle Scholar
ESTEVEZ, I. (2007) Density allowances for broilers: where to set the limits. Poultry Science 86: 1265-1272.CrossRefGoogle ScholarPubMed
ESTEVEZ, I., TABLANTE, N., PETTIT-RILEY, R.L. and CARR, L. (2002) Use of cool perches by broiler chickens. Poultry Science 81: 62-69.CrossRefGoogle ScholarPubMed
EU COUNCIL DIRECTIVE (EUCD), 2007/43/EC 28 June (2007) Laying down minimum rules for the protection of chickens kept for meat production. Official Journal of the European Union L 182: 19-28.Google Scholar
FAO, (2008) FAOSTAT http://faostat.fao.org/site/569/DesktopDefault.aspx?PageID=569#ancor. Last accessed 22 March, 2011.Google Scholar
FANATICO, A.C., PILLAI, P.B., HESTER, P.Y., FALCONE, C., MENCH, J.A., OWENS, C.M. and EMMERT, J.L. (2008) Performance, livability, and carcass yield of slow- and fast-growing chicken genotypes fed low-nutrient or standard diets and raised indoors or with outdoor access. Poultry Science 87: 1012-1021.CrossRefGoogle ScholarPubMed
FUMIERE, O., DUBOIS, M., GREGOIRE, D., THEWIS, A. and BERBEN, G. (2003) Identification on commercialized products of AFLP markers able to discriminate slow- from fast-growing chicken strains. Journal of Agricultural and Food Chemistry 51: 1115-1119.CrossRefGoogle ScholarPubMed
HALEVY, O., KRISPIN, A., LESHEM, Y., MCMURTRY, J.P. and YAHAV, S. (2001) Early-age heat exposure affects skeletal muscle satellite cell proliferation and differentiation in chicks. American Journal of Physiology - Regulatory, Integrative and Comparative Physiology 281: R302-309.CrossRefGoogle ScholarPubMed
HALEVY, O., YAHAV, S. and ROZENBOIM, I. (2006) Enhancement of meat production by environmental manipulations in embryo and young broilers. World's Poultry Science Journal 62: 485-497.Google Scholar
HARRIS, C. (2007) Top poultry companies in Europe. Poultry International, September. Retrieved July 21, 2009, from http://www.wattpoultry.com/Europe_companies.aspx.Google Scholar
HASLAM, S.M., BROWN, S.N., WILKINS, L.J., KESTIN, S.C., WARRISS, P.D. and NICOL, C.J. (2006) Preliminary study to examine the utility of using foot burn or hock burn to assess aspects of housing conditions for broiler chicken. British Poultry Science 47: 13-18.CrossRefGoogle ScholarPubMed
HECKERT, R.A., ESTEVEZ, I., RUSSEK-COHEN, E. and PETTIT-RILEY, R. (2002) Effects of density and perch availability on the immune status of broilers. Poultry Science 81: 451-457.CrossRefGoogle ScholarPubMed
HENDERSON, S.N., BARTON, J.T., WOLFENDEN, A.D., HIGGINS, S.E., HIGGINS, J.P., KUENZEL, W.J., LESTER, C.A., TELLEZ, G. and HARGIS, B.M. (2009) Comparison of beak-trimming methods on early broiler breeder performance. Poultry Science 88: 57-60.CrossRefGoogle ScholarPubMed
HOCKING, P.M., MAXWELL, M.H., ROBERTSON, G.W. and MITCHELL, M.A. (2001) Welfare assessment of modified rearing programmes for broiler breeders. British Poultry Science 42: 424-432.CrossRefGoogle ScholarPubMed
HUGHES, B.O. and ELSON, H.A. (1977) The use of perches by broilers in floor pens. British Poultry Science 18: 715-715.CrossRefGoogle Scholar
JONES, R.B. (1998) Alleviating fear in poultry, in: GREENBERG, G. & HARAWAY, M.M. (Eds.) Comparative Psychology: A Handbook, pp. 339-354. (New York, Garlad Publishing, Inc.).Google Scholar
JONES, T.A., DONNELLY, C.A. and STAMP DAWKINS, M. (2005) Environmental and management factors affecting the welfare of chickens on commercial farms in the United Kingdom and Denmark stocked at five densities. Poultry Science 84: 1155-1165.CrossRefGoogle ScholarPubMed
JONES, T., FEBER, R., HEMERY, G., COOK, P., JAMES, K., LAMBERTH, C. and DAWKINS, M. (2007) Welfare and environmental benefits of integrating commercially viable free-range broiler chickens into newly planted woodland: A UK case study. Agricultural Systems 94: 177-188.CrossRefGoogle Scholar
JULIAN, R.J. (1998) Rapid growth problems: ascites and skeletal deformities in broilers. Poultry Science 77: 1773-1780.CrossRefGoogle ScholarPubMed
JULIAN, R.J. (2005) Production and growth related disorders and other metabolic diseases of poultry: A review. Veterinary Journal (London, England: 1997) 169: 350-369.CrossRefGoogle ScholarPubMed
KALETA, E.F. and REDMANN, T. (2008) Approaches to determine the sex prior to and after incubation of chicken eggs and of day-old chicks. World's Poultry Science Journal 64: 391-399.CrossRefGoogle Scholar
KANNAN, G. and MENCH, J.A. (1996) Influence of different handling methods and crating periods on plasma corticosterone concentrations in broilers. British Poultry Science 37: 21-31.CrossRefGoogle ScholarPubMed
KELLS, A., DAWKINS, M.S. and BORJA, M.C. (2001) The Effect of a 'Freedom Food' enrichment on the behaviour of broilers on commercial farms. Animal Welfare 10: 347-356.CrossRefGoogle Scholar
KNOWLES, T.G., KESTIN, S.C., HASLAM, S.M., BROWN, S.N., GREEN, L.E., BUTTERWORTH, A., POPE, S.J., PFEIFFER, D. and NICOL, C.J. (2008) Leg disorders in broiler chickens: prevalence, risk factors and prevention. PloS One 3: e1545-e1545.CrossRefGoogle ScholarPubMed
KRATZ, S., ROGASIK, J. and SCHNUG, E. (2004) Changes in soil nitrogen and phosphorus under different broiler production systems. Journal of Environmental Quality 33: 1662-1674.CrossRefGoogle ScholarPubMed
KVALØY, O. and TVETERÅ, R. (2008) Cost Structure and Vertical Integration between Farming and Processing. Journal of Agricultural Economics 59: 296-311.CrossRefGoogle Scholar
LEESON, S. and CASTON, L.J. (1993) Production and carcass yield of broiler using free-choice cereal feeding. Journal of Applied Poultry Research 2: 253-258.CrossRefGoogle Scholar
LEONE, E.H. and ESTEVEZ, I. (2008a) Use of space in the domestic fowl: separating the effects of enclosure size, group size and density Animal Behaviour 76: 1673-1682.CrossRefGoogle Scholar
LEONE, E.H. and ESTEVEZ, I. (2008b) Space use according to the distribution of resources and level of competition. Poultry Science 87: 3-13.CrossRefGoogle Scholar
LEONE, E.H. and ESTÉVEZ, I. (2008c) Economic and welfare benefits of environmental enrichment for broiler breeders. Poultry Science 87: 14-21.CrossRefGoogle ScholarPubMed
LEONE, E.H., ESTEVEZ, I. and CHRISTMAN, M.C. (2007) Environmental complexity and group size: immediate effects on use of space by domestic fowl Applied Animal Behaviour Science 102: 39-52.CrossRefGoogle Scholar
LIN, H., JIAO, H.C., BUYSE, J. and DECUYPERE, E. (2006) Strategies for preventing heat stress in poultry. World's Poultry Science Journal 62: 71-86.CrossRefGoogle Scholar
LIU, Y.-P., WU, G.-S., YAO, Y.-G., MIAO, Y.-W., LUIKART, G., BAIG, M., BEJA-PEREIRA, A., DING, Z.-L., PALANICHAMY, M.G. and ZHANG, Y.-P. (2006) Multiple maternal origins of chickens: out of the Asian jungles. Molecular Phylogenetics and Evolution 38: 12-19.CrossRefGoogle ScholarPubMed
MACCALUIM, J.M., ABEYESINGHE, S.M., WHITE, R.P. and WATHES, C.M. (2003) A continuous-choice assessment of the domestic fowl's aversion to concurrent transport stressors. Animal Welfare 12: 95-107.CrossRefGoogle Scholar
MARTRENCHAR, A., HUONNIC, D., COTTE, J.P., BOILLETOT, E. and MORISSE, J.P. (2000) Influence of stocking density, artificial dusk and group size on the perching behaviour of broilers. British Poultry Science 41: 125-130.CrossRefGoogle ScholarPubMed
MCKEEGAN, D.E.F., ABEYESINGHE, S.M., MCLEMAN, M.A., LOWE, J.C., DEMMERS, T.G.M., WHITE, R.P., KRANEN, R.W., VAN BEMMEL, H., LANKHAAR, J.A.C. and WATHES, C.M. (2007) Controlled atmosphere stunning of broiler chickens. II. Effects on behaviour, physiology and meat quality in a commercial processing plant. British Poultry Science 48: 430-442.CrossRefGoogle Scholar
MCKENZIE, M. and WALSH, A. (2009) Pers. Comm. (Ingham's Enterprises).Google Scholar
MELUZZI, A., FABBRI, C., FOLEGATTI, E. and SIRRI, F. (2008) Effect of less intensive rearing conditions on litter characteristics, growth performance, carcase injuries and meat quality of broilers. British Poultry Science 49: 509-515.CrossRefGoogle ScholarPubMed
MENCH, J.A. (2002) Broiler breeders: feed restriction and welfare. World's Poultry Science Journal 58: 23-29.CrossRefGoogle Scholar
MENG, J., HAO, L.P., HOU, H., ILLMANNOVÁ, G., ALONSO, M.E., HANLON, A., ALDAVOOD, S.J., CHOE, B.I., LEE, G.L., HANDZISKA, A., KJASTAD, H., LUND, V., OLSSON, A., REHN, T., KEELING, L.J., PELAGIC, V.R., KENNEDY, M. and PHILLIPS, C.J.C. (2009) Attitudes to animals in Eurasia: the identification of different types of animal protection through an international survey. Abstract number OP061, Minding Animals Conference Book of Abstracts, Newcastle, July, 2009.Google Scholar
MOLLO, M.N., VENDRAMETTO, O. and OKANO, M.T. (2009) Precision livestock tools to improve products and processes in broiler production: a review. Brazilian Journal of Poultry Science 11: 211-218.CrossRefGoogle Scholar
MORRIS, M. (2009) The ethics and politics of animal welfare in New Zealand: broiler chicken production as a case study. Journal of Agricultural and Environmental Ethics 22: 15-30.CrossRefGoogle Scholar
NIELSEN, B.L. (2004) Breast blisters in groups of slow-growing broilers in relation to strain and the availability and use of perches. British Poultry Science 45: 306-315.CrossRefGoogle ScholarPubMed
PEEL, M.C., FINLAYSON, B.L. and MCMAHON, T.A. (2007) Updated world map of the Köppen-Geiger climate classification. Hydrology and Earth System Sciences 11: 1633-1644.CrossRefGoogle Scholar
PETEK, M., SÖNMEZ, G., YILDIZ, H. and BASPINAR, H. (2005) Effects of different management factors on broiler performance and incidence of tibial dyschondroplasia. British Poultry Science 46: 16-21.CrossRefGoogle ScholarPubMed
PETTIT-RILEY, R., ESTEVEZ, I. and RUSSEK-COHEN, E. (2002) Effects of crowding and access to perches on aggressive behaviour in broilers. Applied Animal Behaviour Science 79: 11-25.CrossRefGoogle Scholar
PLAVNIK, I. and BALNAVE, D. (1992) Responses of different strains of Australian broiler chickens to feed restriction at an early age. Australian Journal of Agricultural Research 43: 1253-1258.CrossRefGoogle Scholar
POLLOCK, D.L. (1999) A geneticist's perspective from within a broiler primary breeder company. Poultry Science 78: 414-418.CrossRefGoogle ScholarPubMed
PRAYITNO, D.S., PHILLIPS, C.J. and OMED, H. (1997a) The effects of color of lighting on the behavior and production of meat chickens. Poultry Science 76: 452-457.CrossRefGoogle ScholarPubMed
PRAYITNO, D.S., PHILLIPS, C.J.C. and STOKES, D.K. (1997b) The effects of color and intensity of light on behavior and leg disorders in broiler chickens. Poultry Science 76: 1674-1681.CrossRefGoogle ScholarPubMed
PRIMARY INDUSTRIES STANDING COMMITTEE (PISC), (2002) Model Code of Practice for the Welfare of Animals: Domestic Poultry (4th Ed). (Collingwood, Australia, CSIRO Publishing).Google Scholar
RICHARDS, M.P. and PROSZKOWIEC-WEGLARZ, M. (2007) Mechanisms regulating feed intake, energy expenditure, and body weight in poultry. Poultry Science 86: 1478-1490.CrossRefGoogle ScholarPubMed
ROZENBOIM, I., ROBINZON, B. and ROSENSTRAUCH, A. (1999) Effect of light source and regimen on growing broilers. British Poultry Science 40: 452-457.CrossRefGoogle ScholarPubMed
RSPCA, (2006) Everyone's a Winner - How rearing chickens to higher welfare standards can benefit the chicken, producer, retailer, and consumer. RSPCA (UK), Horsham.Google Scholar
SANDILANDS, V., TOLKAMP, B.J., SAVORY, C.J. and KYRIAZAKIS, I. (2006) Behaviour and welfare of broiler breeders fed qualitatively restricted diets during rearing: Are there viable alternatives to quantitative restriction? Applied Animal Behaviour Science 96: 53-67.CrossRefGoogle Scholar
SCHUMAIER, G., HARRISON, P.C. and MCGINNIS, J. (1968) Effect of colored fluorescent light on growth, cannibalism, and subsequent egg production of single comb white Leghorn pullets. Poultry Science 47: 1599-1602.CrossRefGoogle ScholarPubMed
SCIENTIFIC COMMITTEE on ANIMAL HEALTH, and ANIMAL WELFARE (SCAHAW), (2000) The Welfare Of Chickens Kept For Meat Production (Broilers). Report of the Scientific Committee on Animal Health and Animal Welfare. European Commission, Health and Consumer Protection Directorate-General, Directorate B - Scientific Health Opinions. Unit B3 - Management Of Scientific Committees.Google Scholar
SIEGEL, P.B., PICARD, M., NIR, I., DUNNINGTON, E.A., WILLEMSEN, M.H. and WILLIAMS, P.E. (1997) Responses of meat-type chickens to choice feeding of diets differing in protein and energy from hatch to market weight. Poultry Science 76: 1183-1192.CrossRefGoogle ScholarPubMed
SIMOES, G.S., OBA, A., MATSUO, T., ROSSA, A., SHIMOKOMAKI, M. and IDA, E.I. (2009) Vehicle thermal microclimate evaluation during Brazilian summer broiler transport and the occurrence of PSE (Pale, Soft, Exudative) meat. Brazilian Archives of Biology and Technology52: 195-204.CrossRefGoogle Scholar
SØRENSEN, J.T., EDWARDS, S., NOORDHUIZEN, J. and GUNNARSSON, S. (2006) Animal production systems in the industrialised world. Revue Scientifique et Technique (International Office of Epizootics) 25: 493-503.Google ScholarPubMed
STEVENSON, P. (2009) European and international legislation: a way forward for the protection of farm animals?, in: SANKOFF, P. & WHITE, S. (Eds) Animal Law in Australia, pp 307-332 (Federation Press, Leichardt, Australia).Google Scholar
SU, G., SØRENSEN, P. and KESTIN, S.C. (2000) A note on the effects of perches and litter substrate on leg weakness in broiler chickens. Poultry Science 79: 1259-1263.CrossRefGoogle ScholarPubMed
VAN HORNE, P. and ACHTERBOSCH, T. (2008) Animal welfare in poultry production systems: Impact of EU standards on world trade. World's Poultry Science Journal 64: 40-52.CrossRefGoogle Scholar
VEISSIER, I., BUTTERWORTH, A., BOCK, B. and ROE, E. (2008) European approaches to ensure good animal welfare. Applied Animal Behaviour Science 113: 279-297.CrossRefGoogle Scholar
VOICELESS, (2008) From nest to nugget: an expose΄ of Australia's chicken factories, 36 p. (Paddington, N.S.W, Voiceless Limited).Google Scholar
WINDHORST, H. (2008) Changing patterns of EU poultry meat production and trade. Zootechnica International: World's Poultry Journal. Retrieved November 19, 2009, from http://www.zootecnicainternational.com/index.php?option=com_content&view=article&id=280:changing-patterns-of-eu-poultry-meat-production-and-trade&catid=3:marketing&Itemid=5.Google Scholar
ZULKIFLI, I., GILBERT, J., LIEW, P.K. and GINSOS, J. (2002) The effects of regular visual contact with human beings on fear, stress, antibody and growth responses in meat chicken chickens. Applied Animal Behaviour Science 79: 103-112.CrossRefGoogle Scholar