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Evaluation of euthanasia of sheep with intravenous saturated salt solutions to enable the collection of whole, intact brains

Published online by Cambridge University Press:  01 January 2023

KJ Stanger ,
NJ Kells ,
AD Fisher ,
T Jubb ,
J-L Rault  and
C Johnson
KJ Stanger*
Affiliation:
University of Melbourne, Faculty of Veterinary and Agricultural Sciences, 250 Princes Highway, Werribee, VIC 3030, Australia
NJ Kells
Affiliation:
Animal Welfare Science and Bioethics Centre, Massey University, New Zealand
AD Fisher
Affiliation:
Animal Welfare Science Centre, University of Melbourne, Australia
T Jubb
Affiliation:
Livestock Health Systems Australia, Bendigo, Australia
J-L Rault
Affiliation:
Institute of Animal Welfare Science, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Austria
C Johnson
Affiliation:
Institute of Veterinary, Animal and Biomedical Science, Massey University, New Zealand
*
* Contact for correspondence: [email protected]
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Abstract

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Captive bolts or firearms are unsuitable for euthanasia of livestock when an intact brain is required for diagnostics. Injectable barbiturates can be used, but this method carries risk of poisoning animals eating the carcase. Intravenous saturated salt solutions have been used to euthanase heavily sedated ruminants and are cheap, readily available and not a risk to scavenging animals. However, there is concern that they may be painful or cause distress to animals that are not unconscious. This study aimed to determine the suitability of saturated salt solutions, in combination with xylazine, as a method of euthanasia of ruminants using a sheep model. Thirty-two sheep were sedated with xylazine (0.4 mg kg-1 IM) and euthanased with an intravenous overdose of pentobarbitone (PENT; n = 10), saturated potassium chloride (KCL; n = 11) or saturated magnesium sulphate (MGS; n = 10). Time until end of rhythmic breathing and cardiac arrest, and movement events were recorded. Conscious perception of pain was evaluated by measuring cortical brain activity by electroencephalography (EEG). There was no evidence of perceived pain or unpleasant sensory experience for any treatment as indicated by P50, P95 and Ptot and so all methods were deemed humane. Time until transient EEG was comparable for all treatments. Time until onset of isoelectric EEG was prolonged for KCL. Animals euthanased with KCL consistently exhibited severe reflex movements during infusion (eg kicking, convulsion). No severe movement events were observed in animals euthanased with MGS, hence, physiological and movement data support the preferential use of MGS over KCL.

Keywords

animal welfareelectroencephalogramintravenous euthanasiamagnesium sulphatepotassium chlorideruminant
Type
Articles
Information
Animal Welfare , Volume 28 , Issue 4 , November 2019 , pp. 397 - 406
Copyright
© 2019 Universities Federation for Animal Welfare

References

Animal Health Australia (AHA) 2016a Australian animal wel-fare standards and guidelines for sheep. http://www.animalwelfare-standards.net.au/files/2011/01/Sheep-Standards-and-Guidelines-for-Endorsed-Jan-2016-061017.pdfGoogle Scholar
Animal Health Australia (AHA) 2016b Australian animal wel-fare standards and guidelines for cattle. http://www.animalwelfare-standards.net.au/files/2011/01/Cattle-Standards-and-Guidelines-Endorsed-Jan-2016-061017_.pdfGoogle Scholar
Anon 2017 National TSE Surveillance Project (NTSESP) - National Guidelines for Field Operations. https://animalhealthaustralia.com.au/wp-content/uploads/NTSESP-Field-Guidelines-2017-18_final.pdfGoogle Scholar
Antunes, LM, Golledge, HDR, Roughan, JV and Flecknell, PA 2003 Comparison of electroencephalogram activity and audi-tory evoked responses during isoflurane and halothane anaesthe-sia in the rat. Veterinary Anaesthesia and Analgesia 30: 15–23. https://doi.org/10.1046/j.1467-2995.2003.00085.xCrossRefGoogle ScholarPubMed
Chamberlain, PL and Brynes, SD 1998 The regulatory status of xylazine for use in food-producing animals in the United States. Journal of Veterinary Pharmacology and Therapeutics 21: 322–329. https://doi.org/10.1046/j.1365-2885.1998.00140.xCrossRefGoogle ScholarPubMed
Chang, P, Arendt-Nielsen, L, Graven-Nielsen, T, Svensson, P and Chen, ACN 2001 Different EEG topographic effects of painful and non-painful intramuscular stimulation in man. Experimental Brain Research 141: 195–203. https://doi.org/10.1007/s002210100864CrossRefGoogle ScholarPubMed
Dewell, RD, Bergamasco, LL, Kelly, CK, Shearer, JK, Acaw, D and Dewell, GA 2013 Clinical study to assess the level of unconsciousness in cattle following the administration of high doses of xylazine hydrochloride. Animal Industry Report: AS 660, ASL R2848 660 pp 183–198. https://doi.org/10.31274/ans_air-180814-1134CrossRefGoogle Scholar
Evers, A, Crowder, C and Balser, J 2006 General anaesthetics. In: Brunton, LL, Lazo, JS and Parker, KL (eds) Goodman and Gillman's The Pharmacological Basis of Therapeutics, Eleventh Edition pp 341–363. McGraw-Hill Medical Publishing Division: New York, USAGoogle Scholar
Gibson, TJ, Johnson, CB, Murrell, JC, Hulls, CM, Mitchinson, SL, Stafford, KJ, Johnstone, AC and Mellor, DJ 2009 Electroencephalographic responses of halothane-anaesthetised calves to slaughter by ventral-neck incision without prior stun-ning. New Zealand Veterinary Journal 57: 77–83. https://doi.org/10.1080/00480169.2009.36882CrossRefGoogle Scholar
Grimm, KA, Robertson, SA, Lamont, LA, Tranquilli, WJ and Greene, SA 2015 Veterinary Anesthesia and Analgesia. John Wiley & Sons, Incorporated: Hoboken, US. https://doi.org/10.1002/9781119421375CrossRefGoogle Scholar
Johnson, CB 1996 Some effects of anaesthesia on the electrical activ-ity of the equine brain. PhD Thesis, University of Cambridge, UKGoogle Scholar
Johnson, CB, Bloomfield, M and Taylor, PM 1999 Effects of ketamine on the equine electroencephalogram during anesthesia with halothane in oxygen. Veterinary Surgery 28: 380–385. https://doi.org/10.1111/j.1532-950X.1999.00380.xCrossRefGoogle ScholarPubMed
Kaiser, A, McFarland, W, Siemion, R and Raisbeck, M 2010 Secondary pentobarbital poisoning in two dogs: A cautionary tale. Journal of Veterinary Diagnostic Investigation 22: 632–634. https://oi.org/10.1177/104063871002200423CrossRefGoogle ScholarPubMed
Kästner, SBR 2006 A2-agonists in sheep: a review. Veterinary Anaesthesia and Analgesia 33: 79–96. https://doi.org/10.1111/j.1467-2995.2005.00243.xCrossRefGoogle ScholarPubMed
Kenyon, PR, Maloney, SK and Blache, D 2014 Review of sheep body condition score in relation to production characteristics. New Zealand Journal of Agricultural Research 57: 38–64. https://doi.org/10.1080/00288233.2013.857698CrossRefGoogle Scholar
Leary, S, Underwood, W, Anthony, R and Gwaltney-Brant, S 2013 AVMA Guidelines for the Euthanasia of Animals, 2013 Edition. AMVA: Illinois, USAGoogle Scholar
Mayhew, IG and Washbourne, JR 1990 A method of assessing auditory and brainstem function in horses. British Veterinary Journal 146: 509–518. https://doi.org/10.1016/0007-1935(90)90054-7CrossRefGoogle ScholarPubMed
Menon, V, Sengupta, J and Rossi, J 2019 Cardiogenic shock after myocardial infarction. In: Stouffer, G, Runge, M, Patterson, C and Rossi, J (eds) Netter's Cardiology, Third Edition. Elsevier: Philadelphia, USAGoogle Scholar
Murrell, JC and Johnson, CB 2006 Neurophysiological techniques to assess pain in animals. Veterinary Pharmacology and Therapeutics 29: 325–335. https://doi.org/10.1111/j.1365-2885.2006.00758.xCrossRefGoogle ScholarPubMed
Newhook, JC and Blackmore, DK 1982 Electroencephalographic studies of stunning and slaughter of sheep and calves: Part 1 - The onset of permanent insensibility in sheep during slaughter Meat Science 6: 221–233. https://doi.org/10.1016/0309-1740(82)90031-6CrossRefGoogle ScholarPubMed
Ong, RM, Morris, JP, O’Dwyer, JK, Barnett, JL, Hemsworth, PH and Clarke, IJ 1997 Behavioural and EEG changes in sheep in response to painful acute electrical stimuli. Australian Veterinary Journal 75: 189–193. https://doi.org/10.1111/j.1751-0813.1997.tb10064.xCrossRefGoogle ScholarPubMed
Otto, K and Short, CE 1991 Electroencephalographic power spectrum analysis as a monitor of anesthetic depth in horses. Veterinary Surgery 20: 362–371. https://doi.org/10.1111/j.1532-950X.1991.tb01284.xCrossRefGoogle ScholarPubMed
Payne, J, Farris, R, Parker, G, Bonhotal, J and Schwarz, M 2015 Quantification of sodium pentobarbital residues from equine mortality compost piles. Journal of Animal Science 93: 1824–1829. https://doi.org/10.2527/jas.2014-8193CrossRefGoogle ScholarPubMed
Plumb, DC 2018 Plumb's Veterinary Drug Handbook, Ninth Edition. John Wiley & Sons Inc: Hoboken, USAGoogle Scholar
Raj, ABM 1999 Behaviour of pigs exposed to mixtures of gases and the time required to stun and kill them: welfare implications. Veterinary Record 144: 165–168. https://doi.org/10.1136/vr.144.7.165CrossRefGoogle ScholarPubMed
Rault, JL, Hemsworth, PH, Cakebread, PL, Mellor, DJ and Johnson, CB 2014 Evaluation of microwave energy as a humane stunning technique based on electroencephalography (EEG) of anaesthetised cattle. Animal Welfare 23: 391–400. https://doi.org/10.7120/09627286.23.4.391CrossRefGoogle Scholar
Riviere, JE and Papich, MG 2018 Veterinary Pharmacology and Therapeutics, Tenth Edition. John Wiley & Sons Inc: Hoboken, USAGoogle Scholar
Rumble, JR 2018 CRC Handbook of Chemistry and Physics, 99th Edition. CRC Press/Taylor & Francis: USAGoogle Scholar
Shearer, J 2014 Euthanasia of cattle. Proceedings of the XXVIII World Buiatrics Congress pp 256–258. 27 July-1 Aug 2014, Cairns, QLD, AustraliaGoogle Scholar
Sutherland, MA, Watson, TJ, Johnson, CB and Millman, ST 2016 Evaluation of the efficacy of a non-penetrating captive bolt to euthanase neonatal goats up to 48 hours of age. Animal Welfare 25: 471–479. https://doi.org/10.7120/09627286.25.4.471CrossRefGoogle Scholar
Verhoeven, MTW, Gerritzen, MA, Hellebrekers, LJ and Kemp, B 2015 Indicators used in livestock to assess unconscious-ness after stunning: a review. Animal 9: 320–330. https://doi.org/10.1017/S1751731114002596CrossRefGoogle Scholar