Leg health of meat chickens: impact on welfare, consumer behaviour, and the role of environmental enrichment
D. V. Phibbs
A C , P. J. Groves B and W. I. Muir A
+ Author Affiliations
- Author Affiliations
A School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Camden, NSW 2570, Australia.
B Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Camden, NSW 2570, Australia.
C Corresponding author. Email: danielle.phibbs@sydney.edu.au
Animal Production Science 61(12) 1203-1212 https://doi.org/10.1071/AN19511
Submitted: 6 September 2019 Accepted: 22 April 2021 Published: 8 July 2021
Journal Compilation © CSIRO 2021 Open Access CC BY
Abstract
The Australian and global chicken meat industries have benefited from rapid improvements in the efficiency of chicken meat production that have been predominantly achieved through genetic selection, optimisation of bird nutrition and improved bird health. However, this has also resulted in morphological changes in the bird with an increase in the prevalence of leg health disorders. Compromised leg health can cause pain and lameness and bodes poorly for bird wellbeing, bird mortality, and economic returns. There are also implications for the consumer who is increasingly mindful of animal welfare and is demanding more welfare friendly products. Accurate on-farm assessment of bird leg health has challenges due to the diversity of leg disorders and the variety of techniques used to assess their severity and impact. Overall prevalence of leg disorders shows great variability between properties (farms) and flocks. Opportunities to improve bird leg health have been the focus of considerable research which has frequently included an evaluation of environmental enrichment as a means to reduce lameness and improve bird mobility. To this end, currently in Australia, 78% of chicken meat is produced under the conditions of the Australian RSPCA Approved Farming Scheme, which requires perches in the birds’ environment. However, the value of perches in providing enrichment and improving bird welfare is unclear. Therefore, this review explores animal welfare and consumer attitudes towards meat chicken welfare, describes leg disorders, outlines techniques for assessing leg health and discusses opportunities to enrich the birds’ environment to improve bird mobility and leg health.
Keywords: chicken meat, broilers, animal welfare, poultry diseases, farm management, food production, consumer attitudes, consumer behaviour, lameness, RSPCA Approved Farming Scheme.
References
ABARES (2018) ‘Agricultural commodities: March quarter 2018.’ (Department of Agriculture and Water Resources: ACT, Australia)Allain V, Mirabito L, Arnould C, Colas M, Le Bouquin S, Lupo C, Michel V (2009) Skin lesions in broiler chickens measured at the slaughterhouse: relationships between lesions and between their prevalence and rearing factors. British Poultry Science 50, 407–417.
| Skin lesions in broiler chickens measured at the slaughterhouse: relationships between lesions and between their prevalence and rearing factors.Crossref | GoogleScholarGoogle Scholar | 19735009PubMed |
Animal Health Australia (2019) ‘Animal Welfare Legislation.’ Available at https://www.animalhealthaustralia.com.au/what-we-do/livestock-welfare/animal-welfare-legislation/ [Verified 27 January 2020].
Australian Chicken Meat Federation (2020a) ‘Australian Industry Facts and Figures.’ Available at https://www.chicken.org.au/facts-and-figures/#Retail_Prices_of_Meats [Verified 27 January 2020].
Australian Chicken Meat Federation (2020b) ‘Chicken Health and Welfare.’ Available at https://www.chicken.org.au/chicken-health-welfare/#Chicken_Welfare [Verified 5 December 2020].
Australian Chicken Meat Federation (2020c) ‘Chicken Meat Production.’ Available at https://www.chicken.org.au/chicken-meat-production/ [Verified 27 January 2020].
Aydin A, Cangar O, Ozcan SE, Bahr C, Berckmans D (2010) Application of a fully automatic analysis tool to assess the activity of broiler chickens with different gait scores. Computers and Electronics in Agriculture 73, 194–199.
| Application of a fully automatic analysis tool to assess the activity of broiler chickens with different gait scores.Crossref | GoogleScholarGoogle Scholar |
Bailie CL, O’Connell NE (2015) The influence of providing perches and string on activity levels, fearfulness and leg health in commercial broiler chickens. Animal 9, 660–668.
| The influence of providing perches and string on activity levels, fearfulness and leg health in commercial broiler chickens.Crossref | GoogleScholarGoogle Scholar | 25440236PubMed |
Bailie CL, Ball MEE, O’Connell NE (2013) Influence of the provision of natural light and straw bales on activity levels and leg health in commercial broiler chickens. Animal 7, 618–626.
| Influence of the provision of natural light and straw bales on activity levels and leg health in commercial broiler chickens.Crossref | GoogleScholarGoogle Scholar | 23171519PubMed |
Bailie CL, Baxter M, O’Connell NE (2018) Exploring perch provision options for commercial broiler chickens. Applied Animal Behaviour Science 200, 114–122.
| Exploring perch provision options for commercial broiler chickens.Crossref | GoogleScholarGoogle Scholar |
Baxter M, Bailie CL, O’Connell NE (2018) Evaluation of a dustbathing substrate and straw bales as environmental enrichments in commercial broiler housing. Applied Animal Behaviour Science 200, 78–85.
| Evaluation of a dustbathing substrate and straw bales as environmental enrichments in commercial broiler housing.Crossref | GoogleScholarGoogle Scholar |
Baxter M, Bailie CL, O’Connell NE (2019) Play behaviour, fear responses and activity levels in commercial broiler chickens provided with preferred environmental enrichments. Animal 13, 171–179.
| Play behaviour, fear responses and activity levels in commercial broiler chickens provided with preferred environmental enrichments.Crossref | GoogleScholarGoogle Scholar | 29784068PubMed |
Bench CJ, Oryschak MA, Korver DR, Beltranena E (2017) Behaviour, growth performance, food pad quality, bone density, and carcass traits of broiler chickens reared with barrier perches and fed different dietary crude protein levels. Canadian Journal of Animal Science 97, 268–280.
Berg C, Sanotra GS (2003) Can a modified latency-to-lie test be used to validate gait-scoring results in commercial broiler flocks? Animal Welfare 12, 655–659.
Bessei W (2006) Welfare of broilers: a review. World’s Poultry Science Journal 62, 455–466.
| Welfare of broilers: a review.Crossref | GoogleScholarGoogle Scholar |
Bizeray D, Estevez I, Leterrier C, Faure JM (2002a) Effects of increasing environmental complexity on the physical activity of broiler chickens. Applied Animal Behaviour Science 79, 27–41.
| Effects of increasing environmental complexity on the physical activity of broiler chickens.Crossref | GoogleScholarGoogle Scholar |
Bizeray D, Leterrier C, Constantin P, Picard M, Faure JM (2002b) Sequential feeding can increase activity and improve gait score in meat-type chickens. Poultry Science 81, 1798–1806.
| Sequential feeding can increase activity and improve gait score in meat-type chickens.Crossref | GoogleScholarGoogle Scholar | 12512569PubMed |
Boogaard BK, Oosting SJ, Bock BB (2006) Elements of societal perception of farm animal welfare: a quantitative study in The Netherlands. Livestock Science 104, 13–22.
| Elements of societal perception of farm animal welfare: a quantitative study in The Netherlands.Crossref | GoogleScholarGoogle Scholar |
Brambell R (1965) ‘Report of the technical committee to enquire into the welfare of animals kept under intensive livestock husbandry systems.’ (Her Majesty’s Stationary Office: London, UK)
Brunton C (2009) ‘Chicken Meat Usage and Attitude Survey.’ (RIRDC: ACT, Australia)
Carrigan M, Attalla A (2001) The myth of the ethical consumer - do ethics matter in purchase behaviour? Journal of Consumer Marketing 18, 560–578.
| The myth of the ethical consumer - do ethics matter in purchase behaviour?Crossref | GoogleScholarGoogle Scholar |
Clark B, Stewart GB, Panzone LA, Kyriazakis I, Frewer LJ (2017) Citizens, consumers and farm animal welfare: A meta-analysis of willingness-to-pay studies. Food Policy 68, 112–127.
| Citizens, consumers and farm animal welfare: A meta-analysis of willingness-to-pay studies.Crossref | GoogleScholarGoogle Scholar |
Cobb-Vantress (2021) ‘The challenge and responsibility of using genetics to improve poultry health and welfare.’ Available at https://www.cobb-vantress.com/en_US/articles/the-challenge-and-responsibility-of-using-genetics-to-improve-poultry-health-and-welfare/ [Verified 27 June 2021].
Coleman G, Jongman E, Greenfield L, Hemsworth P (2016) Farmer and public attitudes towards lamb finishing systems. Journal of Applied Animal Welfare Science 19, 198–209.
| Farmer and public attitudes towards lamb finishing systems.Crossref | GoogleScholarGoogle Scholar | 26882113PubMed |
Cornetto T, Estevez I (2001) Behaviour of the domestic fowl in the presence of vertical panels. Poultry Science 80, 1455–1462.
| Behaviour of the domestic fowl in the presence of vertical panels.Crossref | GoogleScholarGoogle Scholar | 11599705PubMed |
Cornish AR, Ashton B, Raubenheimer D, McGreevy PD (2018) Australian consumers’ knowledges and concern for animal welfare in food production: influences and purchasing intentions. Society & Animals 1, 1–22.
Corr SA, Gentle MJ, McCorquodale CC, Bennett D (2003a) The effect of morphology on the musculoskeletal system of the modern broiler. Animal Welfare (South Mimms, England) 12, 145–157.
Corr SA, Gentle MJ, McCorquodale CC, Bennett D (2003b) The effect of morphology on walking ability in the modern broiler: a gait analysis study. Animal Welfare (South Mimms, England) 12, 159–171.
Danbury TC, Weeks CA, Chambers JP, Waterman-Pearson AE, Kestin SC (2000) Self-selection of the analgesic drug carprofen by lame broiler chickens. The Veterinary Record 146, 307–311.
| Self-selection of the analgesic drug carprofen by lame broiler chickens.Crossref | GoogleScholarGoogle Scholar | 10766114PubMed |
Dawkins MS (2008) The science of animal suffering. Ethology 114, 937–945.
| The science of animal suffering.Crossref | GoogleScholarGoogle Scholar |
Dawkins MS, Layton R (2012) Breeding for better welfare: genetic goals for broiler chickens and their parents. Animal Welfare 21, 147–155.
| Breeding for better welfare: genetic goals for broiler chickens and their parents.Crossref | GoogleScholarGoogle Scholar |
Dawkins MS, Donnelly CA, Jones TA (2004) Chicken welfare is influenced more by housing conditions than by stocking density. Nature 427, 342–344.
| Chicken welfare is influenced more by housing conditions than by stocking density.Crossref | GoogleScholarGoogle Scholar | 14737165PubMed |
Dawkins MS, Roberts SJ, Cain RJ, Nickson T, Donnelly CA (2017) Early warning of footpad dermatitis and hockburn in broiler chicken flocks using optical flow, bodyweight and water consumption. The Veterinary Record 180, 499
| Early warning of footpad dermatitis and hockburn in broiler chicken flocks using optical flow, bodyweight and water consumption.Crossref | GoogleScholarGoogle Scholar | 28242781PubMed |
de Jong IC, Gunnink H (2019) Effects of a commercial broiler enrichment programme with or without natural light on behaviour and other welfare indicators. Animal 13, 384–391.
| Effects of a commercial broiler enrichment programme with or without natural light on behaviour and other welfare indicators.Crossref | GoogleScholarGoogle Scholar | 30008274PubMed |
Dinev I (2009) Clinical and morphological investigations on the prevalence of lameness associated with femoral head necrosis in broilers. British Poultry Science 50, 284–290.
| Clinical and morphological investigations on the prevalence of lameness associated with femoral head necrosis in broilers.Crossref | GoogleScholarGoogle Scholar | 19637027PubMed |
Dinev I (2012) Clinical and morphological investigations on the incidence of forms of rickets and their association with other pathological states in broiler chickens. Research in Veterinary Science 92, 273–277.
| Clinical and morphological investigations on the incidence of forms of rickets and their association with other pathological states in broiler chickens.Crossref | GoogleScholarGoogle Scholar | 21450325PubMed |
Dinev I, Denev SA, Edens FW (2012) Comparative clinical and morphological studies on the incidence of tibial dyschondroplasia as a cause of lameness in three commercial lines of broiler chickens. Journal of Applied Poultry Research 21, 637–644.
| Comparative clinical and morphological studies on the incidence of tibial dyschondroplasia as a cause of lameness in three commercial lines of broiler chickens.Crossref | GoogleScholarGoogle Scholar |
Erian I, Phillips CJC (2017) Public understanding and attitudes towards meat chicken production and relations to consumption. Animals 7, 20–28.
| Public understanding and attitudes towards meat chicken production and relations to consumption.Crossref | GoogleScholarGoogle Scholar |
Eshel G, Shepon A, Makov T, Milo R (2014) Land, irrigation water, greenhouse gas, and reaction nitrogen burdens of meat, eggs, and dairy production in the United States. Proceedings of the National Academy of Sciences of the United States of America 111, 11996–12001.
| Land, irrigation water, greenhouse gas, and reaction nitrogen burdens of meat, eggs, and dairy production in the United States.Crossref | GoogleScholarGoogle Scholar | 25049416PubMed |
Estevez I, Tablante NL, Pettit-Riley R, Carr L (2002) Use of cool perches by broiler chickens. Poultry Science 81, 62–69.
| Use of cool perches by broiler chickens.Crossref | GoogleScholarGoogle Scholar | 11885901PubMed |
Farm Animal Welfare Council (2009) ‘Farm Animal Welfare in Great Britain: Past, Present and Future.’ Available at https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/319292/Farm_Animal_Welfare_in_Great_Britain_-_Past__Present_and_Future.pdf [Verified 25 October 2018].
Free Range Egg and Poultry Australia (2012) ‘FREPA Free Range Meat Bird Standards; Chicken.’ (Free Range Egg and Poultry Australia: Victoria, Australia)
Groves PJ, Muir WI (2013) Use of perches by broiler chickens in floor pen experiments. In ‘IX European Symposium on Poultry Welfare. Sweden’, 2013. Uppsala, Uppsala County, Sweden.
Groves PJ, Muir WI (2016) Hock bruises in broilers are indicative of leg weakness. In ‘Australian Poultry Science Symposium. Sydney. Vol. 27’. pp. 59. Sydney, NSW, Australia.
Groves PJ, Muir WI (2017) Earlier hatching time predisposes Cobb broiler chickens to tibial dyschondroplasia. Animal 11, 112–120.
| Earlier hatching time predisposes Cobb broiler chickens to tibial dyschondroplasia.Crossref | GoogleScholarGoogle Scholar | 27297908PubMed |
Hall LE, Shirley RB, Bakalli RI, Aggrey SE, Pesti GM, Edwards HM (2003) Power of two methods for the estimation of bone ash of broilers. Poultry Science 82, 414–418.
| Power of two methods for the estimation of bone ash of broilers.Crossref | GoogleScholarGoogle Scholar | 12705402PubMed |
Hashimoto S, Yamazaki K, Obi T, Takese K (2013) Relationship between severity of footpad dermatitis and carcass performance in broiler chickens. Journal of Veterinary Medical Science 75, 1547–1549.
Haslam SM, Knowles TG, Brown SN, Wilkins LJ, Kestin SC, Warriss PD, Nicol CJ (2007) Factors affecting the prevalence of foot pad dermatitis, hock burn and breast burn in broiler chickens. British Poultry Science 48, 264–275.
| Factors affecting the prevalence of foot pad dermatitis, hock burn and breast burn in broiler chickens.Crossref | GoogleScholarGoogle Scholar | 17578688PubMed |
Heckert RA, Estevez I, Russek-Cohen E, Pettit-Riley R (2002) Effects of density and perch availability on the immune status of broilers. Poultry Science 81, 451–457.
| Effects of density and perch availability on the immune status of broilers.Crossref | GoogleScholarGoogle Scholar | 11989743PubMed |
Hu JY, Hester PY, Makagon MM, Xiong Y, Gates RS, Cheng HW (2019) Effect of cooled perches on physiological parameters of caged White Leghorn hens exposed to cyclic heat. Poultry Science 98, 2317–2325.
| Effect of cooled perches on physiological parameters of caged White Leghorn hens exposed to cyclic heat.Crossref | GoogleScholarGoogle Scholar | 30768132PubMed |
IGA Australia2020 ‘Meat.’ Available at https://igashop.com.au/product-category/meat/
Karaarslan S, Nazlıgül A (2018) Effects of lighting, stocking density, and access to perches on leg health variables as welfare indicators in broiler chickens. Livestock Science 218, 31–36.
| Effects of lighting, stocking density, and access to perches on leg health variables as welfare indicators in broiler chickens.Crossref | GoogleScholarGoogle Scholar |
Kaukonen E, Norring M, Valros A (2016) Effect of litter quality on foot pad dermatitis, hock burns and breast blisters in broiler breeders during the production period. Avian Pathology 45, 667–673.
Kaukonen E, Norring M, Valros A (2017a) Evaluating the effects of bedding materials and elevated platforms on contact dermatitis and plumage cleanliness of commercial broilers and on litter condition in broiler houses. British Poultry Science 58, 480–489.
| Evaluating the effects of bedding materials and elevated platforms on contact dermatitis and plumage cleanliness of commercial broilers and on litter condition in broiler houses.Crossref | GoogleScholarGoogle Scholar | 28604061PubMed |
Kaukonen E, Norring M, Valros A (2017b) Perches and elevated platforms in commercial broiler farms: use and effect on walking ability, incidence of tibial dyschondroplasia and bone mineral content. Animal 11, 864–871.
| Perches and elevated platforms in commercial broiler farms: use and effect on walking ability, incidence of tibial dyschondroplasia and bone mineral content.Crossref | GoogleScholarGoogle Scholar | 27819211PubMed |
Kestin SC, Knowles TG, Tinch AE, Gregory NG (1992) Prevalence of leg weakness in broiler chickens and its relationship with genotype. The Veterinary Record 131, 190–194.
| Prevalence of leg weakness in broiler chickens and its relationship with genotype.Crossref | GoogleScholarGoogle Scholar | 1441174PubMed |
Kierończyk B, Rawski M, Józefiak D, Świątkiewicz S (2017) Infectious and non-infectious factors associated with leg disorders in poultry - a review. Annals of Animal Science 17, 645–669.
| Infectious and non-infectious factors associated with leg disorders in poultry - a review.Crossref | GoogleScholarGoogle Scholar |
Kiyma Z, Küçükyılmaz K, Orojpour A (2016) Effects of perch availability on performance, carcass characteristics, and footpad lesions in broilers. Archiv fur Tierzucht 59, 19–25.
| Effects of perch availability on performance, carcass characteristics, and footpad lesions in broilers.Crossref | GoogleScholarGoogle Scholar |
Knowles TG, Kestin SC, Haslam SM, Brown SN, Green LE, Butterworth A, Pope SJ, Pfeiffer D, Nicol CJ (2008) Leg disorders in broiler chickens: prevalence, risk factors and prevention. PLoS One 3, e1545
| Leg disorders in broiler chickens: prevalence, risk factors and prevention.Crossref | GoogleScholarGoogle Scholar | 18253493PubMed |
Lawrence AB, Conington J, Simm G (2004) Breeding and animal welfare: practical and theoretical advantages of multi-trait selection. Animal Welfare (South Mimms, England) 13, 191–196.
LeVan NF, Estevez I, Stricklin WR (2000) Use of horizontal and angled perches by broiler chickens. Applied Animal Behaviour Science 65, 349–365.
| Use of horizontal and angled perches by broiler chickens.Crossref | GoogleScholarGoogle Scholar |
Malchow J, Berk J, Puppe B, Schrader L (2019) Perches or grids? What do rearing chickens differing in growth performance prefer for roosting? Poultry Science 98, 29–38.
| Perches or grids? What do rearing chickens differing in growth performance prefer for roosting?Crossref | GoogleScholarGoogle Scholar | 30690612PubMed |
McGeown D, Danbury TC, Waterman-Pearson AE, Kestin SC (1999) Effect of carprofen on lameness in broiler chickens. The Veterinary Record 144, 668–671.
| Effect of carprofen on lameness in broiler chickens.Crossref | GoogleScholarGoogle Scholar | 10404606PubMed |
Mellor DJ (2017) Operational details of the five domains model and its key applications to the assessment and management of animal welfare. Animals 7, 60
| Operational details of the five domains model and its key applications to the assessment and management of animal welfare.Crossref | GoogleScholarGoogle Scholar |
Mellor DJ, Beausoleil NJ (2015) Extending the ‘Five Domains’ model for animal welfare assessment to incorporate positive welfare states. Animal Welfare (South Mimms, England) 24, 241–253.
| Extending the ‘Five Domains’ model for animal welfare assessment to incorporate positive welfare states.Crossref | GoogleScholarGoogle Scholar |
Michel V, Prampart E, Mirabito L, Allain V, Arnould C, Huonnic D, Le Bouquin S, Albaric O (2012) Histologically-validated footpad dermatitis scoring system for use in chicken processing plants. British Poultry Science 53, 275–281.
| Histologically-validated footpad dermatitis scoring system for use in chicken processing plants.Crossref | GoogleScholarGoogle Scholar | 22978583PubMed |
Newberry RC, Hunt JR, Gardiner EE (1985) Effect of alternating lights and strain on behaviour and leg disorders of roaster chickens. Poultry Science 64, 1863–1868.
| Effect of alternating lights and strain on behaviour and leg disorders of roaster chickens.Crossref | GoogleScholarGoogle Scholar | 4070125PubMed |
Newberry RC, Hunt JR, Gardiner EE (1986) Light intensity effects on performance, activity, leg disorders and sudden death syndrome of roaster chickens. Poultry Science 65, 2232–2238.
| Light intensity effects on performance, activity, leg disorders and sudden death syndrome of roaster chickens.Crossref | GoogleScholarGoogle Scholar | 3575214PubMed |
Newberry RC, Hunt JR, Gardiner EE (1988) Influence of light intensity on behaviour and performance of broiler chickens. Poultry Science 67, 1020–1025.
| Influence of light intensity on behaviour and performance of broiler chickens.Crossref | GoogleScholarGoogle Scholar | 3222188PubMed |
Nicol CJ, Bouwsema J, Caplen G, Davies G, Hockenhull J, Lambton SL, Lines JA, Mullan S, Weeks CA (2017) ‘Farmed bird welfare science review.’ (Department of Economic Development, Jobs, Transport and Resources: Victoria, Australia)
Nielsen BL (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.
| Breast blisters in groups of slow-growing broilers in relation to strain and the availability and use of perches.Crossref | GoogleScholarGoogle Scholar | 15327116PubMed |
Norring M, Kaukonen E, Valros A (2016) The use of perches and platforms by broiler chickens. Applied Animal Behaviour Science 184, 91–96.
| The use of perches and platforms by broiler chickens.Crossref | GoogleScholarGoogle Scholar |
Ohara A, Oyakawa C, Yoshihara Y, Ninomiya S, Sato S (2015) Effect of environmental enrichment on the behaviour and welfare of Japanese broilers at a commercial farm. Poultry Science 52, 323–330.
| Effect of environmental enrichment on the behaviour and welfare of Japanese broilers at a commercial farm.Crossref | GoogleScholarGoogle Scholar |
OIE World Organisation for Animal Health (2018) ‘Terrestrial Animal Health Code.’ (OIE World Organisation for Animal Health: Paris, France)
Olsson IAS, Keeling LJ (2002) The push-door for measuring motivation in hens: laying hens are motivated to perch at night. Animal Welfare (South Mimms, England) 11, 11–19.
Packialakshmi B, Rath NC, Huff WE, Huff GR (2015) Poultry femoral head separation and necrosis: a review. Avian Diseases 59, 349–354.
| Poultry femoral head separation and necrosis: a review.Crossref | GoogleScholarGoogle Scholar | 26478152PubMed |
Patterson J, Mugera A, Burton M (2015) Consumer preferences for welfare friendly production methods: the case of chicken production in Western Australia. In ‘59th Australian Agricultural & Resource Economy Society Annual Conference’, Rotorua, Bay of Plenty Region, New Zealand.
Pettit-Riley R, Estevez I (2001) Effects of density on perching behaviour of broiler chickens. Applied Animal Behaviour Science 71, 127–140.
| Effects of density on perching behaviour of broiler chickens.Crossref | GoogleScholarGoogle Scholar | 11179565PubMed |
Pichova K, Nordgreen J, Leterrier C, Kostal L, Moe RO (2016) The effects of food-related environmental complexity on litter directed behaviour, fear and exploration of novel stimuli in young broiler chicks. Applied Animal Behaviour Science 174, 83–89.
| The effects of food-related environmental complexity on litter directed behaviour, fear and exploration of novel stimuli in young broiler chicks.Crossref | GoogleScholarGoogle Scholar |
Pines M, Reshef R (2015) ‘Poultry bone development and bone disorders.’ (Elsevier Inc.: New York)
Pines M, Hasdai A, Monsonego-Ornan E (2005) Tibial dyschondroplasia - tools, new insights and future prospects. World’s Poultry Science Journal 61, 285–297.
| Tibial dyschondroplasia - tools, new insights and future prospects.Crossref | GoogleScholarGoogle Scholar |
Primary Industries Standing Committee (2001) ‘Model Code of Practice for the Welfare of Animals: Domestic Poultry.’ (CSIRO Publishing: Melbourne, Vic., Australia)
Riber AB, Van de Weerd HA, De Jong IC, Steenfeldt S (2018) Review of environmental enrichment for broiler chickens. Poultry Science 97, 378–396.
| Review of environmental enrichment for broiler chickens.Crossref | GoogleScholarGoogle Scholar | 29211895PubMed |
Robins A, Phillips CJC (2011) International approaches to the welfare of meat chickens. World’s Poultry Science Journal 67, 351–369.
| International approaches to the welfare of meat chickens.Crossref | GoogleScholarGoogle Scholar |
Rodriguez-Aurrekoetxea A, Leone EH, Estevez I (2015) Effects of panels and perches on the behaviour of commercial slow-growing free-range meat chickens. Applied Animal Behaviour Science 165, 103–111.
| Effects of panels and perches on the behaviour of commercial slow-growing free-range meat chickens.Crossref | GoogleScholarGoogle Scholar |
RSPCA (2013) ‘RSPCA Broiler Welfare Assessment Protocol Ver. 1.1.’ (RSPCA: UK)
RSPCA Australia (2011) ‘Have you got your paw of approval?’ (RSPCA Australia: Australian Capital Territory, Australia)
RSPCA Australia (2013) ‘RSPCA Approved Farming Scheme Standard: Meat Chickens.’ (RSPCA Australia: Australian Capital Territory, Australia)
RSPCA Australia (2018) ‘RSPCA Approved Farming Scheme Impact Report 2018.’ (RSPCA Australia: Australian Capital Territory, Australia)
RSPCA Australia (2020) ‘RSPCA Approved Farming Scheme Standard: Meat Chickens V1.1.’ (RSPCA Australia: ACT, Australia)
Schöder MJA, McEachern MG (2004) Consumer value conflicts surrounding ethical food purchase decisions: a focus on animal welfare. International Journal of Consumer Studies 28, 168–177.
Shepon AEG, Noor E, Milo R (2016) Energy and protein feed-to-food conversion efficiencies in the US and potential food security gains from dietary changes. Environmental Research Letters 11, 105002
| Energy and protein feed-to-food conversion efficiencies in the US and potential food security gains from dietary changes.Crossref | GoogleScholarGoogle Scholar |
Shim MY, Karnuah AB, Mitchell AD, Anthony NB, Pesti GM, Aggrey SE (2012) The effects of growth rate on leg morphology and tibia breaking strength, mineral density, mineral content, and bone ash in broilers. Poultry Science 91, 1790–1795.
| The effects of growth rate on leg morphology and tibia breaking strength, mineral density, mineral content, and bone ash in broilers.Crossref | GoogleScholarGoogle Scholar | 22802169PubMed |
Sørensen P, Su G, Kestin SC (1999) The effect of photoperiod: scotoperiod on leg weakness in broiler chickens. Poultry Science 78, 336–342.
Su G, Sørensen P, Kestin SC (1999) Meal feeding is more effective than early feed restriction at reducing the prevalence of leg weakness in broiler chickens. Poultry Science 78, 949–955.
| Meal feeding is more effective than early feed restriction at reducing the prevalence of leg weakness in broiler chickens.Crossref | GoogleScholarGoogle Scholar | 10404674PubMed |
Su G, Sørensen P, Kestin SC (2000) A note on the effects of perches and litter substrate on leg weakness in broiler chickens. Poultry Science 79, 1259–1263.
| A note on the effects of perches and litter substrate on leg weakness in broiler chickens.Crossref | GoogleScholarGoogle Scholar | 11020069PubMed |
Tablante NL, Estevez I, Russek-Cohen E (2003) Effect of perches and stocking density on tibial dyschondroplasia and bone mineralisation as measured by bone ash in broilers chickens. Journal of Applied Poultry Research 12, 53–59.
| Effect of perches and stocking density on tibial dyschondroplasia and bone mineralisation as measured by bone ash in broilers chickens.Crossref | GoogleScholarGoogle Scholar |
Tahamtani FM, Pedersen IJ, Toinon C, Riber AB (2018) Effects of environmental complexity on fearfulness and learning ability in fast growing broiler chickens. Applied Animal Behaviour Science 207, 49–56.
| Effects of environmental complexity on fearfulness and learning ability in fast growing broiler chickens.Crossref | GoogleScholarGoogle Scholar |
Taylor N, Signal TD (2009) Willingness to pay: Australian consumers and ‘on the farm’ welfare. Journal of Applied Animal Welfare Science 12, 345–359.
| Willingness to pay: Australian consumers and ‘on the farm’ welfare.Crossref | GoogleScholarGoogle Scholar | 20183486PubMed |
Thorp BH (1994) Skeletal disorders in the fowl: a review. Avian Pathology 23, 203–236.
| Skeletal disorders in the fowl: a review.Crossref | GoogleScholarGoogle Scholar | 18671088PubMed |
Thorp BH, Whitehead CC, Dick L, Bradbury JM, Jones RC, Wood A (1993) Proximal femoral degeneration in growing broiler fowl. Avian Pathology 22, 325–342.
| Proximal femoral degeneration in growing broiler fowl.Crossref | GoogleScholarGoogle Scholar | 18671021PubMed |
Toscano MJ, Nasr MAF, Hothersall B (2013) Correlation between broiler lameness and anatomical measurements of bone using radiographical projections with assessments of consistency across and within radiographs. Poultry Science 92, 2251–2258.
| Correlation between broiler lameness and anatomical measurements of bone using radiographical projections with assessments of consistency across and within radiographs.Crossref | GoogleScholarGoogle Scholar | 23960106PubMed |
van Asselt M, Ekkel ED, Kemp B, Stassen EN (2019) The trade-off between chicken welfare and public health risks in poultry husbandry: significance of moral convictions. Nongxue Xuebao 32, 293–319.
| The trade-off between chicken welfare and public health risks in poultry husbandry: significance of moral convictions.Crossref | GoogleScholarGoogle Scholar |
Vasdal G, Vas J, Newberry RC, Moe RO (2019) Effects of environmental enrichment on activity and lameness in commercial broiler production. Journal of Applied Animal Welfare Science 22, 197–205.
| Effects of environmental enrichment on activity and lameness in commercial broiler production.Crossref | GoogleScholarGoogle Scholar | 29623734PubMed |
Velo R, Ceular A (2017) Effects of stocking density, light and perches on broiler growth. Animal Science Journal 88, 386–393.
| Effects of stocking density, light and perches on broiler growth.Crossref | GoogleScholarGoogle Scholar | 27229289PubMed |
Ventura BA, Siewerdt F, Estevez I (2012) Access to barrier perches improves behaviour repertoire in broilers. PLoS One 7, 1–7.
| Access to barrier perches improves behaviour repertoire in broilers.Crossref | GoogleScholarGoogle Scholar |
Wang Y, Lehane C, Ghebremeskel K, Crawford MA (2010) Modern organic and broiler chickens sold for human consumption provide more energy from fat than protein. Public Health Nutrition 13, e29826
| Modern organic and broiler chickens sold for human consumption provide more energy from fat than protein.Crossref | GoogleScholarGoogle Scholar | 20188005PubMed |
Webster AB, Fairchild BD, Cummings TS, Stayer PA (2008) Validation of a three-point gait-scoring system for field assessment of walking ability of commercial broilers. Journal of Applied Poultry Research 17, 529–539.
| Validation of a three-point gait-scoring system for field assessment of walking ability of commercial broilers.Crossref | GoogleScholarGoogle Scholar |
Welfare Quality® (2009) ‘Welfare Quality® assessment protocol for poultry (broilers, laying hens).’ (Welfare Quality® Consortium: Lelystad, Netherlands)
Wideman RFJ (2016) Bacterial chondronecrosis with osteomyelitis and lameness in broilers: a review. Poultry Science 95, 325–344.
| Bacterial chondronecrosis with osteomyelitis and lameness in broilers: a review.Crossref | GoogleScholarGoogle Scholar |
Wideman RF, Rhoads DD, Erf GF, Anthony NB (2013) Pulmonary arterial hypertension (ascites syndrome) in broilers: a review. Poultry Science 92, 64–83.
| Pulmonary arterial hypertension (ascites syndrome) in broilers: a review.Crossref | GoogleScholarGoogle Scholar | 23243232PubMed |
Wijesurendra DS, Chamings AN, Bushell RN, O’Rourke D, Stevenson M, Marenda MS, Noormohammadi AH, Stent A (2017) Pathological and microbiological investigations into cases of bacterial chondronecrosis and osteomyelitis in broiler poultry. Avian Pathology 46, 683–694.
| Pathological and microbiological investigations into cases of bacterial chondronecrosis and osteomyelitis in broiler poultry.Crossref | GoogleScholarGoogle Scholar | 28669198PubMed |
Wong L, Selvanathan EA, Selvanathan S (2015) Modelling the meat consumption patterns in Australia. Economic Modelling 49, 1–10.
| Modelling the meat consumption patterns in Australia.Crossref | GoogleScholarGoogle Scholar |
Woolworths Group Limited (2020) ‘Chicken.’ Available at https://www.woolworths.com.au/shop/browse/meat-seafood-deli/meat/chicken [Verified 5 December 2020].
Yildirim M, Taskin A (2017) The effects of environmental enrichment on some physiological and behavioural parameters of broiler chicks. Brazilian Journal of Poultry Science 19, 355–362.
| The effects of environmental enrichment on some physiological and behavioural parameters of broiler chicks.Crossref | GoogleScholarGoogle Scholar |
