Abstract
Fish welfare at harvest is easily compromised by poor choice of handling and slaughter methods, lack of attention to detail and by unnecessary adherence to fish farming traditions. The harvest process comprises fasting the fish to empty the gut, crowding the fish, gathering and moving the fish using brails, fish pumps, and sometimes also road or boat transport and finally stunning and killing the fish. The harvesting processes commonly used for bass, bream, carp, catfish, cod, eel, halibut, pangasius, salmon, tilapia, trout, tuna and turbot are outlined. These harvesting processes are discussed; the consequences for fish welfare identified and practical tests which can be made at the harvest site highlighted. Welfare at harvest for the majority of farmed fish species can be improved by adopting and adapting existing procedures already known to be beneficial for fish welfare through their use in other fish farming systems or with other species. It is seldom necessary to develop completely new concepts or methods.
Similar content being viewed by others
References
Álvarez A, García García B, Garrido MD, Hernández MD (2008) The influence of starvation time prior to slaughter on the quality of commercial-sized gilthead seabream (Sparus aurata) during ice storage. Aquaculture 284:106–114
Ashley P (2007) Fish welfare: current issues in aquaculture. Appl Anim Behav Sci 104:199–235
Bagni M, Civitareale C, Priori A, Ballerini A, Finoia M, Brambilla G, Marino G (2007) Pre-slaughter crowding stress and killing procedures affecting quality and welfare in sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata). Aquaculture 263:52–60
Brown JA, Watson J, Bourhill A, Wall A (2010) Physiological welfare of commercially reared cod and effects of crowding for harvesting. Aquaculture 298:315–324
EFSA (2009a) General approach to fish welfare and to the concept of sentience in fish. Scientific opinion of the panel on animal health and welfare. EFSA J 954:1–27
EFSA (2009b) Species-specific welfare aspects of the main systems of stunning and killing of farmed seabass and seabream. EFSA J 1010:1–52
EFSA (2009c) Species-specific welfare aspects of the main systems of stunning and killing of farmed atlantic salmon. EFSA J 2012:1–77
EFSA (2009d) Species-specific welfare aspects of the main systems of stunning and killing of farmed fish: rainbow trout. EFSA J 1013:1–55
EFSA (2009e) Species-specific welfare aspects of the main systems of stunning and killing of farmed carp. EFSA J 1013:1–37
EFSA (2009f) Species-specific welfare aspects of the main systems of stunning and killing of farmed eels (Anguilla anguilla). EFSA J 1014:1–42
EFSA (2009g) Species-specific welfare aspects of the main systems of stunning and killing of farmed tuna. EFSA J 1072:1–53
EFSA (2009h) Species-specific welfare aspects of the main systems of stunning and killing of farmed turbot. EFSA J 1073:1–34
Erikson U (2011) Assessment of different stunning methods and recovery of farmed Atlantic salmon: isoeugenol, nitrogen, and three levels of carbon dioxide. Anim Welf 20:365–375
Foss A et al (2009) Compensatory growth in Atlantic halibut: effect of starvation and subsequent feeding on growth, maturation, feed utilization and flesh quality. Aquaculture 290:304–310
Foss A, Grimsbø E, Vikingstad E, Nortvedt R, Slinde E, Roth B (2011) Live chilling of Atlantic salmon: physiological response to handling and temperature decrease on welfare. Fish Physiol Biochem. doi:10.1007/s10695-011-9536-6
Ginés R, Palicio M, Zamorano MJ, Argüello A, López JL, Afonso JM (2002) Starvation before slaughtering as a tool to keep freshness attributes in gilthead sea bream (Sparus aurata). Aquacult Int 10:379–389
HSA (2005) Humane harvesting of salmon and trout. Guidance notes no 5. The Humane Slaughter Association, Herts. http://www.hsa.org.uk. ISBN 1 871561 29 9
HSA (2008) Humane harvesting of halibut. Technical note 24 Humane Slaughter Association, Herts. Available at http://www.hsa.org.uk
Kestin SC, van de Vis JW, Robb DHF (2002) Protocol for assessing brain function in fish and the effectiveness of methods used to stun and kill them. Vet Rec 150:302–307
Kiessling A, Johansson D, Zahl IH, Samuelsen OB (2009) Pharmacokinetics, plasma cortisol and effectiveness of benzocaine, MS-222 and isoeugenol measured in individual dorsal aorta-cannulated Atlantic salmon (Salmo salar) following bath administration. Aquaculture 286:301–308
Lambooij E, Kloosterboer RJ, Gerritzen MA, van de Vis JW (2006) Assessment of electrical stunning in fresh water of African catfish (Clarias gariepinus) and chilling in ice water for loss of consciousness and sensibility. Aquaculture 254:388–395
Lambooij E, Pilarczyk M, Bialowas H, van den Boogaart JGM, van de Vis JW (2007) Electrical and percussive stunning of the common carp (Cyprinus carpio L.): neurological and behavioural assessment. Aquac Eng 37:171–179
Lambooij B, Gerritzen MA, Reimert H, Burggraaf D, André G, Van De Vis H (2008) Evaluation of electrical stunning of sea bass (Dicentrarchus labrax) in seawater and killing by chilling: welfare aspects, product quality and possibilities for implementation. Aquacult Res 39:50–58
Lambooij E, Grimbø E, van de Vis JW, Reimert H, Nortvedt R, Roth B (2010) Percussion and electrical stunning of Atlantic salmon (Salmo salar) after dewatering and subsequent effect on brain and heart activities. Aquaculture 300:107–112
Lines JA, Kestin SC (2004) Electrical stunning of fish: the relationship between the electric field strength and water conductivity. Aquaculture 241:219–234
Lines JA, Kestin SC (2005) Electric stunning of trout: power reduction using a two-stage stun. Aquac Eng 32:483–491
Marx H, Sengmuller-Sieber T, Hoffmann R, Stolle A (1999) Untersuchungen zu Stressbelastung und Produktqualität von Forelle, Wels und Flunder in Zusammenhang mit Betäubung und Schlachtung. Archiv für Lebensmittelhygiene 50:37–40
Mørkøre T, Mazo TP, Tahirovic V, Einen O (2008) Impact of starvation and handling stress on rigor development and quality of Atlantic salmon (Salmon salar L.). Aquaculture 277:231–238
Ortuño J, Esteban M, Meseguer J (2001) Effects of short-term crowding stress on the gilthead seabream (Sparus aurata L.) innate immune response. Fish Shellfish Immunol 11:187–197
Regost C, Arzel J, Cardinal M, Laroche M, Kaushik SJ (2001) Fat deposition and flesh quality in seawater reared, triploid brown trout (Salmo trutta) as affected by dietary fat levels and starvation. Aquaculture 193:325–345
Robb DHF (2008) Welfare of fish at harvest. In: Branson EJ (ed) Fish welfare. Blackwell Publishing, London, pp 217–242
Robb DHF, Kestin SC (2002) Methods used to kill fish: field observations and literature reviewed. Anim Welf 11:269–282
Robb DHF, Roth B (2003) Brain activity of Atlantic salmon (Salmo salar) following electrical stunning using various field strengths and pulse durations. Aquaculture 216:363–369
Robb DHF, O’Callaghan MO, Lines JA, Kestin SC (2002) Electrical stunning of rainbow trout (oncorhynchus mykiss): factors that affect stun duration. Aquaculture 205:359–371
Roth B, Moeller D, Slinde E (2004) Ability of electric field strength, frequency and current duration to stun farmed Atlantic salmon and pollock and relations to observed injuries using sinusoidal and square wave alternating current. N Am J Aquac 66:208–216
Roth B, Imsland AK, Foss A (2009) Live chilling of turbot and subsequent effect on behaviour, muscle stiffness, muscle quality, blood gases and chemistry. Anim Welf 2009(18):33–41
RSPCA Welfare Standards for Farmed Atlantic Salmon (2010) RSPCA, Wilberforce Way, West Sussex. ISBN 1898331685
van de Vis JH, Kestin SC, Robb DHF, Oehlenschläger J, Lambooij E, Münkner W, Kuhlmann W, Kloosterboer K, Tejada M, Huidobro A, Tejada M, Otterå H, Roth B, Sørensen NK, Aske L, Byrne H, Nesvadba P (2003) Is humane slaughter of fish possible for industry? Aquacult Res 34:211–220
VKM (2010) Risikovurdering knyttet til bruk av gass, slag mot hode og strøm til bedøving av fisk: Uttalelse fra Faggruppe for dyrehelse og dyrevelferd i Vitenskapskomiteen for mattrygghet. http://www.english.vkm.no/dav/f942fb5728.pdf. Last accessed 13 May 2011
Wall AJ (2001) Ethical considerations in the handling and slaughter of farmed fish. In: Kestin SC, Warriss PD (eds) Farmed fish quality. Fishing News Books, Blackwell science, Oxford, pp 108–115
Webster AJF (2001) Farm animal welfare: the five freedoms and the free market. Vet J 161:229–237
Zahl HI, Kiessling A, Samuelsen OB and Olsen RE (2009) Anaesthesia induces stress in Atlantic salmon (Salmo salar), Atlantic cod (Gadus morhua) and Atlantic halibut (Hippoglossus hippoglossus). Fish Physiol Biochem. Published online 13 August 2009. doi:10.1007/s10695-009-9346-2
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Lines, J.A., Spence, J. Safeguarding the welfare of farmed fish at harvest. Fish Physiol Biochem 38, 153–162 (2012). https://doi.org/10.1007/s10695-011-9561-5
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10695-011-9561-5