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The effect of stun duration and level of applied current on stun and meat quality of electrically stunned lambs under commercial conditions

Published online by Cambridge University Press:  01 January 2023

C Berg ,
C Nordensten ,
J Hultgren  and
B Algers
C Berg*
Affiliation:
Department of Animal Environment and Health, Swedish University of Agricultural Sciences, PO Box 234, SE 532 23 Skara, Sweden
C Nordensten
Affiliation:
Section of Ruminants and Pigs, Division of Animal Welfare and Health, Swedish Board of Agriculture, SE-551 82 Jönköping, Sweden
J Hultgren
Affiliation:
Department of Animal Environment and Health, Swedish University of Agricultural Sciences, PO Box 234, SE 532 23 Skara, Sweden
B Algers
Affiliation:
Department of Animal Environment and Health, Swedish University of Agricultural Sciences, PO Box 234, SE 532 23 Skara, Sweden
*
* Contact for correspondence and requests for reprints: Lotta.Berg@slu.se
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Abstract

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Electrical head-only stunning is a widely used method in sheep (Ovis aries) slaughter. To investigate the influence of current level on stun and meat quality in practice, two studies were carried out at a commercial slaughterhouse. In trial one, 200 lambs were randomly assigned to four groups with a current level of 0.6, 0.8, 1.0 and 1.25 A, respectively, using 50-Hz sine wave supply voltage and a stun duration of 10.5 s. In trial two, 135 lambs were randomly assigned to two groups, with electrical current of 1.25 A applied for 14 and 3 s. For each lamb, the position of the tongs was observed and classified as correct or incorrect. The stun quality was evaluated based on observations of the corneal reflex, eye movements, rhythmic breathing, head-righting reflex and kicking during the tonic phase. Blood splash (haemorrhages in Longissimus dorsi muscle) was evaluated four days after slaughter. Incorrect tongs’ positioning was seen commonly, and positively correlated with poor stun quality. The lowest current level tested produced an unsatisfactory stun in the majority of animals observed. Short stun duration increased the risk of a poor stun quality. There was no significant effect of current level, stun duration or tongs’ position on the risk of blood splash. These data underline the importance of a correct technique, including choice of tongs’ positioning, sufficient current levels and sufficient stun duration, for electrical stunning of lambs to achieve unconsciousness before sticking and thereby avoiding unnecessary suffering at commercial slaughter.

Keywords

animal welfareblood splashelectrical stunningsheepslaughterstun quality
Type
Papers
Information
Animal Welfare , Volume 21 , Issue S2: Proceedings of the HSA Centenary International Symposium ‘Recent Advances in the Welfare of Livestock at Slaughter’ Historic Dockyard, Portsmouth, UK, 2011 , June 2012 , pp. 131 - 138
Copyright
© 2012 Universities Federation for Animal Welfare

References

Cook, CJ, Devine, CE, Gilbert, KV, Smith, DD and Maasland, SA 1995 The effect of head-only stun duration on electroencephalographic-measured seizure and brain amino acid neurotransmitter release. Meat Science 40: 137–147. http://dx.doi.org/10.1016/0309-1740(94)00043-7CrossRefGoogle ScholarPubMed
Council of Europe 1991 Council of Europe Recommendation No R (91) 7 on the Slaughter of Animals. Council of Europe: Brussels, BelgiumGoogle Scholar
Croft, PG and Hume, CW 1956 Electric stunning of sheep. The Veterinary Record 68: 318–321Google Scholar
EFSA 2004 Welfare aspects of Animal Stunning and Killing Methods. European Food Safety Authority, AHAW/04-027 Report. EFSA: Parma, ItalyGoogle Scholar
European Union 2009 Council Regulation (EC) No 1099/2009 of 24 September 2009 on the Protection of Animals at the Time of Killing. EU: Brussels, BelgiumGoogle Scholar
Gregory, NG 1998 Animal Welfare and Meat Science. CABI Publishing: Wallingford, UKGoogle Scholar
Gregory, NG 2007 Animal Welfare and Meat Production, Second Edition. CABI Publishing: Wallingford, UKCrossRefGoogle Scholar
Gregory, NG and Wotton, SB 1985 Sheep slaughtering procedures IV. Responsiveness of the brain following electrical stunning. British Veterinary Journal 141: 74–81CrossRefGoogle ScholarPubMed
Humane Slaughter Association 2005 Electrical Stunning of Red Meat Animals. Guidance Notes No 4. HSA: Wheathampstead, Herts, UKGoogle Scholar
Jordbruksverket 2007 Statens jordbruksverks föreskrifter och allmänna råd (SJVFS 2007:77, Saknr L22) om slakt och annan avlivning av djur. Jordbruksverket: Jönköping, Sweden. [Title translation: Swedish Board of Agriculture, Regulations and recommendations on the welfare of animals at slaughter and killing]Google Scholar
Kirton, A, Bishop, W and Mullord, M 1978 Relationships between time of stunning and time of throat cutting and their effect on blood pressure and blood splash in lambs. Meat Science 2: 199–206. http://dx.doi.org/10.1016/0309-1740(78)90005-0CrossRefGoogle ScholarPubMed
Kirton, A, Frazerhurst, LF, Woods, EG and Chrystall, BB 1980 Effect of electrical stunning method and cardiac arrest on bleeding efficiency, residual blood and blood splash in lambs. Meat Science 5: 347–353. http://dx.doi.org/10.1016/0309-1740(81)90033-4CrossRefGoogle Scholar
Lambooy, E 1982 Electrical stunning of sheep. Meat Science 6: 123–135. http://dx.doi.org/10.1016/0309-1740(82)90022-5CrossRefGoogle ScholarPubMed
Linares, MB, Bórnez, R and Vergara, H 2007 Effect of different stunning systems on meat quality of light lamb. Meat Science 76: 675–681CrossRefGoogle ScholarPubMed
Restall, DJ 1980 Blood splash in lambs: a preliminary study using the one-stage prothrombin time test. Meat Science 5: 1215–129Google Scholar
Velarde, A, Gispert, M, Diestre, A and Manteca, X 2003 Effect of electrical stunning on meat and carcass quality in lambs. Meat Science 63: 35–38. http://dx.doi.org/10.1016/S0309-1740(02)00049-9CrossRefGoogle ScholarPubMed
Velarde, A, Ruiz-de-la-Torre, JL, Stub, C, Diestre, and Manteca, X 2000 Factors affecting the effectiveness of head-only electrical stunning in sheep. Veterinary Record 147: 40–43CrossRefGoogle ScholarPubMed
Velarde, A, Ruiz-de-la-Torre, JL, Rosello, C, Farbrega, E, Diestre, A and Manteca, X 2002 Assessment of return to consciousness after electrical stunning in lambs. Animal Welfare 11: 333–341CrossRefGoogle Scholar
Vergara, H, Linares, MB, Berruga, MI and Galleo, L 2005 Meat quality in suckling lambs: effect of pre-slaughter handling. Meat Science 69: 473–478.http://dx.doi.org/10.1016/j. meatsci.2004.09.002CrossRefGoogle ScholarPubMed
Warriss, P 2010 Meat Science, Second Edition. CABI Publishing: Wallingford, UKGoogle Scholar
Williams, R 2006 Generalized ordered logit/partial proportional odds models for ordinal dependent variables. The Stata Journal 6: 58–82CrossRefGoogle Scholar