Research and Reviews : A Journal of Life Sciences Review Article

Rethinking Stocking Density in Broilers: Assessments of Physiological, Behavioral, and Environmental Impacts

  1. Md. Emran Hossain Department of Animal Science and Nutrition, Chattogram Veterinary and Animal Sciences University, Khulshi

Abstract

High stocking density in broiler production is a common practice aimed at maximizing space utilization and economic returns. However, it poses significant challenges to the performance, health, and welfare of the birds. This study explores the multifaceted impacts of elevated stocking density on broiler chickens, highlighting the physiological, behavioral, and environmental factors that deteriorate their overall well-being. Increased stocking density is associated with reduced growth rates, poor feed conversion efficiency, compromised immune function, and heightened susceptibility to respiratory diseases. Additionally, overcrowding impairs welfare through limited mobility, increased incidence of leg disorders, feather pecking, and stress-related behaviors, while also exacerbating litter quality and ammonia buildup, further contributing to health risks. The study examines how these adverse effects cumulatively result in higher mortality rates and reduced productivity, underscoring the need for optimal stocking density management to ensure sustainable broiler production. The findings emphasize the importance of balancing economic considerations with animal welfare and health to promote both ethical and productive poultry farming practices.

Keywords

References (38)

  1. E. L. T. Chung, N. A. A. Bakar, N. A. A. Fauzi, F. F. A. Jesse, and T. C. Loh, “How Stocking Density Affects Broiler Chicken Production? A Comprehensive Review,” Poult. Sci. J., 2026, Accessed: Mar. 27, 2026. [Online]. Available: https://search.ebscohost.com/login.aspx?direct=true&profile=ehost&scope=site&authtype=crawler&jrnl=23456604&AN=191554848&h=YLM03iPVL2GUSWdlLCiFFXrKWIUZCXNQg3%2FhFCKsTTE6MlwpduY08CtGOaHVVX1OYy0Ndt1h%2BDEy40je5Ll%2BVA%3D%3D&crl=c
  2. Bai D, Guo C, Ma P, Wang Z, Zhao X, Ma X, et al. Comprehensive analysis of the effects of high stocking density stress on broiler health. Frontiers in Veterinary Science. 2026;12. doi:10.3389/fvets.2025.1741407
  3. Naeem M. Improving bone health in broiler chickens: integrating population density, housing, and nutritional strategies for enhanced welfare and productivity. Poultry Science and Management. 2025;2(1). doi:10.1186/s44364-025-00017-y
  4. Zhou S, Watcharaanantapong P, Yang X, Thornton T, Gan H, Tabler T, et al. Evaluating broiler welfare and behavior as affected by growth rate and stocking density. Poultry Science. 2024;103(4):103459. doi:10.1016/j.psj.2024.103459
  5. B. Tainika, A. Şekeroğlu, A. Akyol, and Z. Waithaka Ng’ang’a, “Effect of stocking density on broilers behaviour and welfare indices,” journals.ekb.eg, vol. 79, no. 2, pp. 285–329, 2023, doi:10.1080/00439339.2023.2175343.
  6. Shynkaruk T, Long K, LeBlanc C, Schwean-Lardner K. Impact of stocking density on the welfare and productivity of broiler chickens reared to 34 d of age. Journal of Applied Poultry Research. 2023;32(2):100344. doi:10.1016/j.japr.2023.100344
  7. EFSA AHAW Panel (EFSA Panel on Animal Health and Welfare), Nielsen SS, Alvarez J, Bicout DJ, Calistri P, Canali E, et al. Welfare of broilers on farm. EFSA Journal. 2023;21(2). doi:10.2903/j.efsa.2023.7788
  8. van der Eijk JAJ, Gunnink H, Melis S, van Riel JW, de Jong IC. Reducing stocking density benefits behaviour of fast- and slower-growing broilers. Applied Animal Behaviour Science. 2022;257:105754. doi:10.1016/j.applanim.2022.105754
  9. K. K. Thema, C. M. Mnisi, and V. Mlambo, “Dietary strategies to alleviate high-stocking-density-induced stress in broiler chickens–a comprehensive review,” aab.copernicus.org, vol. 17, no. 10 October, Oct. 2022, doi:10.1371/journal.pone.0275811.
  10. Son J, Kim HJ, Hong EC, Kang HK. Effects of Stocking Density on Growth Performance, Antioxidant Status, and Meat Quality of Finisher Broiler Chickens under High Temperature. Antioxidants. 2022;11(5):871. doi:10.3390/antiox11050871
  11. El Sabry MI, Hassan SSA, Zaki MM, Stino FKR. Stocking density: a clue for improving social behavior, welfare, health indices along with productivity performances of quail (Coturnix coturnix)—a review. Tropical Animal Health and Production. 2022;54(1). doi:10.1007/s11250-022-03083-0
  12. Zabir M, Miah M, Alam M, Bhuiyan M, Haque M, Sujan K, et al. Impacts of stocking density rates on welfare, growth, and hemato-biochemical profile in broiler chickens. Journal of Advanced Veterinary and Animal Research. 2021;8(4):1. doi:10.5455/javar.2021.h556
  13. S. Jhetam, “The impact of stocking density on the performance, health and welfare of turkey hens,” 2021, Accessed: Mar. 27, 2026. [Online]. Available: https://harvest.usask.ca/bitstream/10388/13514/1/JHETAM-THESIS-2021.pdf
  14. Van Limbergen T, Sarrazin S, Chantziaras I, Dewulf J, Ducatelle R, Kyriazakis I, et al. Risk factors for poor health and performance in European broiler production systems. BMC Veterinary Research. 2020;16(1). doi:10.1186/s12917-020-02484-3
  15. De Jong IC, Guémené D. Major welfare issues in broiler breeders. World's Poultry Science Journal. 2011;67(1):73-82. doi:10.1017/s0043933911000067
  16. S. Meseret, “A review of poultry welfare in conventional production system,” Livest. Res. Rural Dev., vol. 28, no. 12, 2016, Accessed: Mar. 27, 2026. [Online]. Available: https://www.researchgate.net/profile/Selam-Meseret/publication/311321712_A_review_of_poultry_welfare_in_conventional_production_system/links/58419bc908ae8e63e6218f2e/A-review-of-poultry-welfare-in-conventional-production-system.pdf
  17. Karaarslan S, Nazlıgül A. Effects of lighting, stocking density, and access to perches on leg health variables as welfare indicators in broiler chickens. Livestock Science. 2018;218:31-36. doi:10.1016/j.livsci.2018.10.008
  18. Thomas D, Ravindran V, Thomas D, Camden B, Cottam Y, Morel P, et al. Influence of stocking density on the performance, carcass characteristics and selected welfare indicators of broiler chickens. New Zealand Veterinary Journal. 2004;52(2):76-81. doi:10.1080/00480169.2004.36408
  19. McLean JA, Savory CJ, Sparks NHC. Welfare of Male and Female Broiler Chickens in Relation to Stocking Density, as Indicated by Performance, Health and Behaviour. Animal Welfare. 2002;11(1):55-73. doi:10.1017/s0962728600024313
  20. Abudabos AM, Samara EM, Hussein EOS, Al-Ghadi MAQ, Al-Atiyat RM. Impacts of Stocking Density on the Performance and Welfare of Broiler Chickens. Italian Journal of Animal Science. 2013;12(1):e11. doi:10.4081/ijas.2013.e11
  21. Estevez I. Density Allowances for Broilers: Where to Set the Limits? Poultry Science. 2007;86(6):1265-1272. doi:10.1093/ps/86.6.1265
  22. Simitzis PE, Kalogeraki E, Goliomytis M, Charismiadou MA, Triantaphyllopoulos K, Ayoutanti A, et al. Impact of stocking density on broiler growth performance, meat characteristics, behavioural components and indicators of physiological and oxidative stress. British Poultry Science. 2012;53(6):721-730. doi:10.1080/00071668.2012.745930
  23. BESSEI W. Welfare of broilers: a review. World's Poultry Science Journal. 2006;62(03):455-466. doi:10.1079/wps2005108
  24. Erasmus MA. A review of the effects of stocking density on turkey behavior, welfare, and productivity. Poultry Science. 2017;96(8):2540-2545. doi:10.3382/ps/pex075
  25. RAVINDRAN V, THOMAS DV, THOMAS DG, MOREL PCH. Performance and welfare of broilers as affected by stocking density and zinc bacitracin supplementation. Animal Science Journal. 2006;77(1):110-116. doi:10.1111/j.1740-0929.2006.00327.x
  26. Bailie CL, Ijichi C, O’Connell NE. Effects of stocking density and string provision on welfare-related measures in commercial broiler chickens in windowed houses. Poultry Science. 2018;97(5):1503-1510. doi:10.3382/ps/pey026
  27. Houshmand M, Azhar K, Zulkifli I, Bejo MH, Kamyab A. Effects of prebiotic, protein level, and stocking density on performance, immunity, and stress indicators of broilers. Poultry Science. 2012;91(2):393-401. doi:10.3382/ps.2010-01050
  28. Skrbic Z, Pavlovski Z, Lukic M, Petricevic V, Djukic-Stojcic M, Zikic D. The effect of stocking density on individual broiler welfare parameters: 2. Different broiler stocking densities. Biotechnology in Animal Husbandry. 2011;27(1):17-24. doi:10.2298/bah1101017s
  29. Li XM, Zhang MH, Liu SM, Feng JH, Ma DD, Liu QX, et al. Effects of stocking density on growth performance, growth regulatory factors, and endocrine hormones in broilers under appropriate environments. Poultry Science. 2019;98(12):6611-6617. doi:10.3382/ps/pez505
  30. Goo D, Kim JH, Park GH, Delos Reyes JB, Kil DY. Effect of stocking density and dietary tryptophan on growth performance and intestinal barrier function in broiler chickens. Poultry Science. 2019;98(10):4504-4508. doi:10.3382/ps/pez215
  31. Nicol CJ, Brown SN, Glen E, Pope SJ, Short FJ, Warriss PD, et al. Effects of stocking density, flock size and management on the welfare of laying hens in single-tier aviaries. British Poultry Science. 2006;47(2):135-146. doi:10.1080/00071660600610609
  32. MARTRENCHAR A, HUONNIC D, COTTE JP, BOILLETOT E, MORISSE JP. Influence of stocking density on behavioural, health and productivity traits of turkeys in large flocks. British Poultry Science. 1999;40(3):323-331. doi:10.1080/00071669987403
  33. Hall AL. The Effect of Stocking Density on the Welfare and Behaviour of Broiler Chickens Reared Commercially. Animal Welfare. 2001;10(1):23-40. doi:10.1017/s096272860002323x
  34. Najafi P, Zulkifli I, Amat Jajuli N, Farjam AS, Ramiah SK, Amir AA, et al. Environmental temperature and stocking density effects on acute phase proteins, heat shock protein 70, circulating corticosterone and performance in broiler chickens. International Journal of Biometeorology. 2015;59(11):1577-1583. doi:10.1007/s00484-015-0964-3
  35. Tsiouris V, Georgopoulou I, Batzios C, Pappaioannou N, Ducatelle R, Fortomaris P. High stocking density as a predisposing factor for necrotic enteritis in broiler chicks. Avian Pathology. 2015;44(2):59-66. doi:10.1080/03079457.2014.1000820
  36. Buijs S, Keeling L, Rettenbacher S, Van Poucke E, Tuyttens FAM. Stocking density effects on broiler welfare: Identifying sensitive ranges for different indicators. Poultry Science. 2009;88(8):1536-1543. doi:10.3382/ps.2009-00007
  37. Meluzzi A, Sirri F. Welfare of broiler chickens. Italian Journal of Animal Science. 2009;8(sup1):161-173. doi:10.4081/ijas.2009.s1.161
  38. Hall AL. The Effect of Stocking Density on the Welfare and Behaviour of Broiler Chickens Reared Commercially. Animal Welfare. 2001;10(1):23-40. doi:10.1017/s096272860002323x
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