Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-20T07:30:34.676Z Has data issue: false hasContentIssue false

Effect of amount and frequency of head-only stunning currents on the electroencephalogram and somatosensory evoked potentials in broilers

Published online by Cambridge University Press:  11 January 2023

ABM Raj*
Affiliation:
Department of Clinical Veterinary Science, University of Bristol, Langford, Bristol BS40 5DU, UK
M O'Callaghan
Affiliation:
Department of Clinical Veterinary Science, University of Bristol, Langford, Bristol BS40 5DU, UK
*
* Contact for correspondence and requests for reprints: [email protected]
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.

The effectiveness of head-only electrical stunning of broilers, with a root mean square (RMS) current of 100 or 150mA delivered using either 50, 400 or 1500Hz sine wave alternating current (AC), was investigated. The changes occurring in the spontaneous electroencephalogram (EEG) were evaluated using Fast Fourier Transformations (FFT) to determine the impact of the amount and frequency of stunning current on total (2-30 Hz) and relative (13-30 Hz) power contents in the EEG. Induction of epileptiform activity and reduction in the EEG power contents to less than 10% of pre-stun levels from the end of epileptiform activity were used as indicators of effective stunning. The duration of unconsciousness and insensibility was determined on the basis of the return of EEG power contents. In addition, the changes occurring in somatosensory evoked potentials (SEPs) were subjectively evaluated to determine the impact of stunning treatments. The results of ANOVA (repeated measures) showed statistically significant effects of interactions between the current frequencies, amount of current and repeated measures on changes in EEG power contents (P < 0.001). Stunning broilers with 150 mA delivered using 50 Hz resulted in EEG changes that were indicative of more pronounced neuronal inhibition following epileptiform activity and also lasted longer than was the case when broilers were stunned with 150 mA delivered using 400 Hz. Stunning broilers with 100 mA delivered using 50 Hz resulted in changes very similar to those observed after stunning with 150 mA of 50 Hz, but which lasted for a relatively shorter time. However, these changes were more pronounced and lasted longer than did stunning with 100 mA delivered using 400 Hz. The effects of stunning broilers with 150 mA of 400 Hz were similar to those found after stunning with 100 mA of 50 Hz. By contrast, stunning broilers with 100 mA of 1500 Hz failed to fulfil the criteria set out in this study. Stunning of broilers with 150 mA of 1500 Hz induced epileptiform activity but failed to reduce EEG power contents to less than 10% of pre-stun levels. Therefore, the stunning of broilers with 100 or 150 mA of 1500 Hz may not be adequate to avoid pain and suffering during slaughter. Thus, minimum currents of 100, 150 and 200 mA should be delivered whilst using 50, 400 and 1500 Hz, respectively, to achieve effective electrical stunning in broilers. Severing of the carotid arteries in the neck following head-only electrical stunning, and high frequency (> 125 Hz) electrical water bath stunning of broilers should also become a statutory requirement to prevent the return of consciousness during bleeding.

Type
Research Article
Copyright
© 2004 Universities Federation for Animal Welfare

References

Cepeda, C, Radisanljevic, Z, Peacock, W, Levine, M S and Buchwald, N A 1992 Differential modulation by dopamine of responses evoked by excitatory amino acids in human cortex. Synapse 11: 330341CrossRefGoogle ScholarPubMed
Cook, C J, Devine, C E, Gilbert, K V, Smith, D D and Maasland, S A 1995 The effects of electrical head-only stun duration on electroencephalographic-measured seizures and brain amino acid neurotransmitter release. Meat Science 40: 137147CrossRefGoogle ScholarPubMed
Cook, C J, Devine, C E, Tavener, A and Gilbert, K V 1992 Contribution of amino acid transmitters to epileptiform activity and reflex suppression in electrically head stunned sheep. Research in Veterinary Science 52: 4856CrossRefGoogle ScholarPubMed
Cook, C J, Maasland, S A, Devine, C E, Gilbert, K V and Blackmore, D K 1996 Changes in the release of amino acid neurotransmitters in the brains of calves and sheep after head-only electrical stunning and throat cutting. Research in Veterinary Science 60: 255261CrossRefGoogle ScholarPubMed
Dreifuss, F E and Ogunyemi, A O 1992 Classification of epileptic seizures and the epilepsies: an overview. Epilepsy Research Supplement 6: 311Google ScholarPubMed
Durstewitz, D, Kroner, S and Gunturkun, O 1999 The dopaminergic innervation of the avail telencephalon. Progress in Neurobiology 59: 161195CrossRefGoogle Scholar
Godbout, R, Mantz, J, Pirot, S, Glowinski, J and Thierry, A M 1991 Inhibitory influence of the mesocortical dopaminergic neurones on their target cells: electrophysiological and pharmacological characterisation. Journal of Pharmacology and Experimental Therapeutics 258: 728738Google Scholar
Gregory, N G 1986 The physiology of electrical stunning and slaughter. In: Universities Federation for Animal Welfare (ed) Humane Slaughter of Animals for Food pp 312. Universities Federation for Animal Welfare: Wheathampstead, Herts, UKGoogle Scholar
Gregory, N G and Wotton, S B 1986 Effect of slaughter on the spontaneous and evoked activity of the brain. British Poultry Science 27: 195205CrossRefGoogle ScholarPubMed
Gregory, N G and Wotton, S B 1987 Effect of electrical stunning on the electroencephalogram in chickens. British Veterinary Journal 143: 175183CrossRefGoogle ScholarPubMed
Gregory, N G and Wotton, S B 1989 Effect of electrical stunning on somatosensory evoked potentials in chickens. British Veterinary Journal 145: 159164CrossRefGoogle ScholarPubMed
Gregory, N G and Wotton, S B 1990a Effect of stunning on spontaneous physical activity and evoked activity in the brain. British Poultry Science 31: 215220CrossRefGoogle ScholarPubMed
Gregory, N G and Wotton, S B 1990b An evaluation of the effectiveness of handheld stunners for stunning chickens. The Veterinary Record 126: 290291Google ScholarPubMed
Gregory, N G and Wotton, S B 1991 Effect of a 350 Hz DC stunning current on evoked responses in the chicken's brain. Research in Veterinary Science 50: 250251CrossRefGoogle ScholarPubMed
Gruss, M and Braun, K 1997 Distinct activation of monoaminergic pathways in chick brain in relation to auditory imprinting and stressful situations: a microdialysis study. Neuroscience 76: 891899CrossRefGoogle ScholarPubMed
Hoenderken, R 1978 Electrical stunning of slaughter pigs. PhD Thesis, University of Utrecht, The NetherlandsGoogle Scholar
Hughes, R J and John, E R 1999 Conventional and quantitative electroencephalography in psychiatry. Journal of Neuropsychiatry and Clinical Neuroscience 11: 190208CrossRefGoogle ScholarPubMed
Krystal, A D and Weiner, R D 1999 EEG correlates of the response to ECT: a possible antidepressant role of brain-derived neurotrophic factor. The Journal of ECT 15: 2738CrossRefGoogle ScholarPubMed
Kuenzel, W J and Walther, J H 1978 Heart rate, blood pressure, respiration and brain waves of broilers as affected by electrical stunning and bleed-out. Poultry Science 57: 655659CrossRefGoogle Scholar
Lambooy, E 1981 Some neural and physiological aspects of electrical and mechanical stunning in ruminants. PhD Thesis, University of Utrecht, The NetherlandsGoogle Scholar
Lukatch, H S, Echon, R M, Maclver, M B and Werchan, P M 1997 G-force induced alterations in rat EEG activity: a quantitative analysis. Electroencephalography and Clinical Neurophysiology 103: 563573CrossRefGoogle ScholarPubMed
Meldrum, B 1984 Amino acid neurotransmitters and new approaches to anticonvulsant drug action. Epilepsia 25: 5140-5149 (Suppl)CrossRefGoogle Scholar
Meldrum, B 1994 The role of glutamate in epilepsy and other CNS disorders. Neurology 44: 514523 (Suppl)Google ScholarPubMed
Raj, A B M and O’ Callaghan, M 2004 Effect of electrical water bath stunning current frequencies on the spontaneous electroencephalogram and somatosensory evoked potentials in hens. British Poultry Science 45 (April)CrossRefGoogle Scholar
Raj, A B M, Wotton, S B, McKinstry, J L, Hillebrand, S J W and Pieterse, C 1998 Changes in the somatosensory evoked potentials and spontaneous electroencephalogram of broiler chickens during exposure to gas mixtures. British Poultry Science 39: 686695CrossRefGoogle ScholarPubMed
Richards, S A and Sykes, A H 1967 Physiological effects of electrical stunning and venesection in the fowl. Research in Veterinary Science 8: 361368CrossRefGoogle ScholarPubMed
Rolls E T, Thorpe S J, Boytim M, Szabo l and Perrett D l 1984 Responses of striatal neurones in the behaving monkey. 3. Effects of ionophorotically applied dopamine on normal responsiveness. Neuroscience 12: 12011212CrossRefGoogle Scholar
Schutt-Abraham, l, Wormuth, H-J, Fessel, J and Knapp, J 1983 Electrical stunning of poultry in view of animal welfare and meat production. In: G Eikelenboom (ed) Stunning of Animals for Slaughter pp 187196. Martinus Nijhoff: The Hague, The NetherlandsGoogle Scholar
Sparrey, J M and Kettlewell, P J 1994 Shackling of poultry: is it a welfare problem? World's Poultry Science Journal 50: 167176CrossRefGoogle Scholar
Sparrey, J M, Kettlewell, P J, Paice, M E R and Whetlor, W C 1993 Development of a constant current waterbath stunner for poultry processing. Journal of Agricultural and Engineering Research 56: 267274CrossRefGoogle Scholar
Velarde, A, Ruiz-de-Torre, J L, Rosello, C, Fabrega, E, Diestre, A and Manteca, X 2002 Assessment of return to consciousness after electrical stunning in lambs. Animal Welfare 11: 333341Google Scholar
Wang, L-Y and Kaczmarek, L K 1998 High frequency firing helps replenish readily releasable pool of synaptic vesicles. Nature 394: 384388CrossRefGoogle ScholarPubMed
Wilkins, L J, Gregory, N G, Wotton, S B and Parkman, l D 1998 Effectiveness of electrical stunning applied using a variety of waveform-frequency combinations and consequences for carcass quality in broilers. British Poultry Science 39: 511518CrossRefGoogle Scholar