Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-11T03:01:59.017Z Has data issue: false hasContentIssue false
  • English
  • Français

Relationship between the response to the corneal reflex (depth of narcosis) and specific parameters in the slaughter blood of pigs narcotised with CO2

Published online by Cambridge University Press:  01 January 2023

H Hartmann ,
G Rindermann ,
C Siegling-Vlitakis ,
G Arndt ,
K Wolf  and
R Fries
H Hartmann*
Affiliation:
Institute of Veterinary Physiology, Department of Veterinary Medicine, Free University of Berlin, Oertzenweg 19b, D-14163 Berlin, Germany
G Rindermann
Affiliation:
Institute of Meat Hygiene and Technology, Department of Veterinary Medicine, Free University of Berlin, Oertzenweg 19b, D-14163 Berlin, Germany
C Siegling-Vlitakis
Affiliation:
Institute of Veterinary Physiology, Department of Veterinary Medicine, Free University of Berlin, Oertzenweg 19b, D-14163 Berlin, Germany
G Arndt
Affiliation:
Institute for Biometrics and Data Processing, Department of Veterinary Medicine, Free University of Berlin, Oertzenweg 19b, D-14163 Berlin, Germany
K Wolf
Affiliation:
Institute of Veterinary Physiology, Department of Veterinary Medicine, Free University of Berlin, Oertzenweg 19b, D-14163 Berlin, Germany
R Fries
Affiliation:
Institute of Meat Hygiene and Technology, Department of Veterinary Medicine, Free University of Berlin, Oertzenweg 19b, D-14163 Berlin, Germany
*
* Contact for correspondence and requests for reprints: hehart@zedat.fu-berlin.de
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

There has been insufficient research into CO2 stunning with regard to its effect on pigs being slaughtered. This lack of knowledge may be at least partly responsible for the partial rejection of CO2-stunning methods. During routine slaughter work, 598 pigs (average carcase weight: 94 kg) were evaluated. The stunning procedure was carried out in industrial stunning chambers with 90% CO2 by volume and an exposure time of either 120 or 90 s. The corneal reflex response was evaluated immediately prior to bleeding in order to determine the depth of narcosis. Blood was taken at slaughter (slaughter blood) to determine the partial pressure of breathing gases and the acid-base status. We found that CO2 stunning mainly produced hypoxaemia, but also normoand hyperoxaemia, in arteriovenous slaughter blood. No further positive reflex responses occurred at a pO2 threshold of ≤ 1.6 kPa. PCO2 increased to values of 40 kPa and above. This extreme hypercapnia resulted in a decrease of the slaughter blood pH with values of less than 7.00 (ie, strong respiratory acidosis). Starting with threshold values from pCO2 > 23 kPa and pH < 6.85, stunned pigs revealed only a few or no positive reflex responses, respectively. The non-respiratory Stewart-variable serum [SID3] was elevated to alkaline values of 65 mmol L−1 and above, in comparison to the normal values of 45 (± 2) mmol L−1. We conclude that the use of cut-off points such as the pH and/or pO2 in routine sampling of slaughter animals (eg by application of ion-sensitive electrodes) would establish the depth of narcosis in pigs destined for slaughter. The efficiency of monitoring could thereby be improved during slaughter, in line with the demands of animal welfare.

Keywords

acid-base parameteranimal welfareblood-gas tensionCO2 stunningcorneal reflex responsepigs
Type
Research Article
Information
Animal Welfare , Volume 19 , Issue 4 , November 2010 , pp. 515 - 522
Copyright
© 2010 Universities Federation for Animal Welfare

References

Allen, DG, Lamb, GD and Westerblad, H 2008 Skeletal muscle fatigue: cellular mechanisms. Physiological Review 88: 287–332CrossRefGoogle ScholarPubMed
Anonymous 2003 Stellungnahme zum Entwurf des Berichtes des Lebensmittel- und Veterinäramtes über den Inspektionsbesuch in Deutschland, 19.-23 Mai 2003. Bewertung der Kontrollen des Schutzes von Tieren beim Transport und zum Zeitpunkt der Schlachtung. http://ec.europa.eu/food/fs/inspections/vi/reports/germany/vi_rep_germ_9038-2003cm_de.pdf, 2003. [Title translation: Statement of the Office for Foods and Veterinary Medicine referring to the drafted report of the inspection visit on 19-23 May, 2003 in Germany. Evaluation of the controls of the animal protection during the transportation and the time of slaughtering]Google Scholar
Barford, K 1990 Carbon dioxide anaesthetization of pigs. Fleischwirtschaft 70: 1174Google Scholar
Becker, K 2005 Anästhesie bei Versuchstieren. http://www.ag-wolfrum.bio.uni-mainz.de/Dateien/Vor110-Narkose.pdf. [Title translation: Anaesthesia of lab animals]Google Scholar
Bennett, PB and Hayward, AJ 1967 Electrolyte imbalance as the mechanism for inert gas narcosis and anaesthesia. Nature 208: 938–939CrossRefGoogle Scholar
Berencsy, G 2005 Die Wirkung der Inhalation von CO2 auf das Elektrokardiogramm der Tiere. Journal Molecular Medicine 13: 587–589. [Title translation: The effect of CO2 inhalation on the ECG of animals]Google Scholar
Burnett, RW, Covington, AK, Fogh-Andersen, N, Kuelpmann, WR, Maas, AH, Mueller-Plathe, O, Siggaard-Andersen, O, van Kessel, AL, Wimberley, PD and Zijlstra, WG 1995 International Federation of Clinical Chemistry (IFCC). Scientific Division. Committee on pH, Blood Gases and Electrolytes. Approved IFCC recommendations on whole blood sampling, transport and storage for simultaneous determinations of pH, blood gases and electrolytes. European Journal Clinical Chemistry Clinical Biochemistry 33: 247–253Google Scholar
Buschulte, A, Rindermann, G, Hartmann, H and Fries, R 2007 Abschließende Ergebnisse aus dem Projekt CO2-Betäubung und Pneumonie. FU Berlin, 7. Fachtag Fleisch- und Geflügelfleischhygiene 01.-02.03.2007, 39-47. [Title translation: Final results of the project, CO2 anaesthesia and pneumonia]Google Scholar
Cantieni, J 1977 Ein Beitrag zur CO2-Betäubung von Schlachtschweinen. Schweizerisches Archiv Tierheilkunde 119: 355–375. [Title translation: A contribution to CO2 stunning of slaughter pigs]Google Scholar
Corbach, S 2006 Untersuchung der CO2-Euthanasie bei Labormäusen auf Tierschutzgerechtigkeit. PhD Thesis, Tierärztliche Hochschule, Hannover, Germany. [Title translation: Investigation into animal protection justice and the CO2 euthanasia of lab mice]Google Scholar
Engelhardt von, W 2005 Kreislauf. In: von Engelhardt, W and Breves, G (eds) Physiologie der Haustiere pp 171–192. Enke-Verlag: Stuttgart, Germany. [Title translation: Circulation]Google Scholar
Erhardt, W, Ring, C, Kraft, H, Schmidt, A, Weinmann, HM, Ebert, R, Schläger, B, Schindele, M, Heinze, R, Lomholt, N, Kallweit, E, Henning, M, Unshelm, J, Berner, H and Blümel, G 1989 Die CO2-Betäubung von Schlachtschweinen aus anästhe-siologischer Sicht. Deutsche Tierärztliche Wochenschrift 96: 92–99. [Title translation: CO2 stunning of slaughter pigs from the anaes-thesiological point of view]Google Scholar
Farver, TB 2008 Concepts of normality in clinical biochemistry. In: Kaneko, JJ, Harvey, JW and Bruss, ML (eds) Clinical Biochemistry of Domestic Animals pp 1–25. Elsevier Academic Press: Amsterdam, The NetherlandsGoogle Scholar
Folbergrová, J, MacMillan, V and Siesjö, BK 1972 The effect of moderate and marked hypercapnia upon the energy state and upon the cytoplasmatic NADH/NAD+ ratio of the rat brain. Journal Neurochemical 19: 2497–2505Google Scholar
Forslid, A and Augustinsson, O 1988 Acidosis, hypoxia and stress hormone release in response to one-minute inhalation of 80% CO2 in swine. Acta Physiology Scandinavia 132: 223–231CrossRefGoogle ScholarPubMed
Greiner, M, Pfeiffer, D and Smith, RD 2000 Principles and practical application of the receiver-operating characteristic analysis for diagnostics tests. Preview Veterinary Medicine 45: 23–41Google Scholar
Gros, G 2005 Atmung. In: Engelhardt, W and Breves, G (eds) Physiologie der Haustiere pp 230–267. Enke-Verlag: Stuttgart, GermanyGoogle Scholar
Gu, XQ, Kanaan, A, Yao, H and Haddad, GG 2007 Chronic high-inspired CO2 decreases excitability of mouse hippocampal neurons. Journal Neurophysiology 97: 1833–1838CrossRefGoogle ScholarPubMed
Hannon, JP, Bossone, CA and Wade, CE 1990 Normal physiological values for conscious pigs used in biomedical research. Laboratory Animal Science 40: 293–299Google ScholarPubMed
Hartmann, H and Berchtold, J 2009 Klinische Bedeutung der Parameter des Säuren-Basen-Status nach Henderson-Hasselbalch und nach Stewart für die Diagnostik und Therapieüberwachung bei Tieren. Tierärztliche Praxis 37G: 205-213. [Title translation: Clinical relevance of the parameter of acid-base status after Henderson-Hasselbalch and after Stewart for diagnostic and therapy check in animals]Google Scholar
Hertrampf, B and von Mickwitz, G 1979 Betäubung von Schlachttieren. Teil I: CO2-Betäubung. Deutsche Tierärztliche Wochenschrift 86: 444–451. [Title translation: Anaesthesia of slaughter animals, part 1, CO2 stunning]Google Scholar
Jaresch, H 2001 Betäubung und Schlachtung. http://www.tierschutz.de/p10002000x1018x14.html. [Title translation: Stunning and slaughtering]Google Scholar
Kanaan, A, Douglas, RM, Alper, SL, Boron, WF and Haddad, GG 2007 Effect of chronic elevated carbon dioxide on the expression of acid-base transporters in the neonatal and adult mouse. American Journal Physiology, Regulatory Integrative Companion Physiology 293: R1294–R1302CrossRefGoogle ScholarPubMed
Kaneko, JJ, Harvey, JW and Bruss, ML 2008 Clinical Biochemistry of Domestic Animals. Appendix VIII Blood Analyte Reference Values in Large Animals pp 882–888. Elsevier Academic Press: Amsterdam, The NetherlandsGoogle Scholar
Kaplan, LJ, Philbin, N, Arnaud, F, Rice, J, Dong, F and Freilich, D 2006 Resuscitation from hemorrhagic shock: fluid selection and infusion strategy drives unmeasured ion genesis. Journal Traumatic 61: 90–98CrossRefGoogle ScholarPubMed
Kawai, A, Onimaru, H and Homma, I 2006 Mechanisms of CO2/H+ chemoreception by respiratory rhythm generator neurons in the medulla from newborn rats in vitro. Journal Physiology 572: 525–537CrossRefGoogle ScholarPubMed
Kowalchuk, JM, Heigenhauser, GJF, Lindinger, MI, Obminski, G, Sutton, JR and Jones, NL 1988 Role of lungs and inactive muscle in acid-base control after maximal exercise. Journal Applied Physiology 65: 2090–2096CrossRefGoogle ScholarPubMed
Lagerweij, E 1990 CO2 inhalation in the pig. Fleischwirtschaft 70: 1162–1163Google Scholar
Machold, U, Troeger, K and Moje, M 2003a Betäubung von Schweinen mit Kohlendioxid (CO2) bzw. Argon. Vergleichende Verhaltensstudie und Bestimmung humoraler Stressparameter. Fleischwirtschaft 83(9): 139–142. [Title translation: Observation of behaviour and measuring of blood stress parameters in pigs stunned with CO2 or argon]Google Scholar
Machold, U, Troeger, K and Moje, M 2003b Gasbetäubung von Schweinen. Ein Vergleich von Kohlendioxid, Argon, einer Stickstoff-Argon-Mischung und Argon/Kohlendioxid (2-stufig) unter Tierschutzaspekten. Fleischwirtschaft 83(10): 109–114. [Title translation: Gas stunning in pigs: a comparison of carbon dioxide, argon, a nitrogen-argon-mixture and argon/carbon dioxide (2 steps system) under animal welfare aspects]Google Scholar
Martoft, L 2001 Neurophysiological effects of high concentration CO2-inhalation in swine. PhD Thesis, Royal Agricultural University Frederiksberg, DenmarkGoogle Scholar
Martoft, L, Lomholt, L, Kolthoff, C, Rodriguez, BE, Jensen, EW, J⊘rgensen, PF, Pedersen, HD and Forslid, A 2002 Effects of CO2 anaesthesia on central nervous system activity in swine. Laboratory Animals 36: 115–126CrossRefGoogle ScholarPubMed
Nowak, B and Hartung, J 2006 Kann die CO2-Betäubung von Schlachtschweinen tiergerecht sein? Hannover, Forschungsmagazin Stiftung Tierärztliche Hochschule 48-51. [Title translation: Can CO2 stunning of slaughter pigs be animal friendly]Google Scholar
Raj, ABM 1999 Behaviour of pigs exposed to mixture of gases and the time required to stun and kill them: welfare implications. Veterinary Record 144: 165–168CrossRefGoogle ScholarPubMed
Raj, ABM and Gregory, NG 1995 Welfare implications of the gas stunning pigs: 1. Determination of aversion to the initial inhalation of carbon dioxide or argon. Animal Welfare 4: 273–280Google Scholar
Raj, ABM and Gregory, NG 1996 Welfare implications of the gas stunning pigs: 2. Stress of induction of anaesthesia. Animal Welfare 5: 71–78Google Scholar
Raj, ABM, Johnson, SP, Wotton, SB and McInstry, JL 1997 Welfare implications of gas stunning pigs: 3. the time to loss of somatosensory evoked potentials and spontaneous electrocorticogram of pigs during exposure to gases. Veterinary Journal 153: 329–340CrossRefGoogle ScholarPubMed
Reinhold, P, Hartmann, H and Constable, PD 2010 Characterisation of acid-base abnormalities in pigs experimentally infected with Chlamydia suis. The Veterinary Journal 184: 212–218CrossRefGoogle ScholarPubMed
Remien, D 2001 Gasmessungen bei der Kohlendioxidbetäubung von Schweinen in einem ausgewählten Schlachtbetrieb. PhD Thesis, Tierärztliche Hochschule, Hanover, Germany. [Title translation: Gas treatments at the carbon dioxide stunning in a selected abattoir]Google Scholar
Richter, DW 2008 Towards strategies for the treatment of respiratory network dysfunctions with serotonin. Göttingen, Atmungsphysiologischer Arbeitstagung, 25.01.-26.01.2008.Google Scholar
Rindermann, G 2008 Pneumonien bei Mastschweinen und ihr Einfluss auf den Betäubungseffekt in der CO2-Betäubung. PhD Thesis, Freie Universität, Fachbereich Veterinärmedizin, Germany. [Title translation: Pneumonia at fattened pigs and their influence on the stunning effect in CO2 anaesthesia]Google Scholar
Siesjö, BK 1985 Acid-base homeostasis in the brain: physiology, chemistry, and neurochemical pathology. Progress Brain Research 63: 121–154CrossRefGoogle ScholarPubMed
Stockham, SL and Scott, MA 2008 Fundamentals of Veterinary Clinical Pathology pp 1–51. Blackwell Publishing: Oxford, UKGoogle Scholar
Troeger, K and Moje, M 2000 Untersuchungen zur Verbesserung des Tierschutzes bei der Gasanästhesie von Schlachtschweinen. Mitteilungsblatt der BAFF 39: 689–694. [Title translation: Investigations to improve animal welfare after gas stunning of slaughter pigs]Google Scholar
von Brandis, HJ and Killian, H 1931 Versuche über das Optimum der Kohlensäurewirkungen beim normalen und beim narkotisierten Tier. Deutsche Zeitschrift Chirurgie 233: 97–108. [Title translation: Experiments about the optimum of the carbonic acid effects at both normal and anaesthetised animals]CrossRefGoogle Scholar
Woodbury, DM and Karler, R 1960 The role of carbon dioxide in the nervous system. Anaesthesiology 21: 686–703Google ScholarPubMed
Young, KC and Peracchia, C 2004 Opposite Cx32 and Cx26 voltage-gating response to CO2 reflects opposite voltage-gating polarity. Journal Membrane Biology 202: 161–170CrossRefGoogle ScholarPubMed