Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-19T04:26:38.740Z Has data issue: false hasContentIssue false
  • English
  • Français

The effects of amount and frequency of pulsed direct current used in water bath stunning and of slaughter methods on spontaneous electroencephalograms in broilers

Published online by Cambridge University Press:  11 January 2023

ABM Raj ,
M O'Callaghan  and
SI Hughes
ABM Raj*
Affiliation:
School of Clinical Veterinary Science, University of Bristol, Langford BS40 5DU, UK
M O'Callaghan
Affiliation:
School of Clinical Veterinary Science, University of Bristol, Langford BS40 5DU, UK
SI Hughes
Affiliation:
School of Clinical Veterinary Science, University of Bristol, Langford BS40 5DU, UK
*
* Contact for correspondence and requests for reprints: M.Raj@bristol.ac.uk
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 electrical water bath stunning of broilers (n = 96) for 1 s with a constant average current of 100, 150 or 200 mA delivered using a variable voltage/constant current stunner with 200, 800 or 1400 Hz pulsed direct current (DC), with a mark:space ratio of 1:1, followed by slaughter using a unilateral or ventral neck cutting procedure, was evaluated. The results of a binary logistic model showed that both the electrical frequency and average current had significant effects on the probability of inducing epileptiform electroencephalogram (EEG) and therefore, of effective stunning. The results of univariate analysis showed that only slaughter method had highly significant effects on the power contents in the 13–30 Hz and 2–30 Hz EEG frequency bands. Based on these results, it is recommended that a minimum of 200 mA average (400 mA peak) current per bird should be delivered using 200 Hz pulsed DC, with a mark:space ratio of 1:1, to achieve effective water bath stunning in 80% of broilers. Frequencies of above 200 Hz pulsed DC would presumably require average currents of greater than 200 mA. Electrical water bath stunning of broilers with 200 mA average current of 200 Hz resulted in cardiac arrest in six out of eight broilers that showed epileptiform activity. Two other broilers that had cardiac arrest showed no epileptiform EEGs indicative of effective stunning. Owing to the prevalence of cardiac arrest in conscious broilers, the use of pulsed DC for water bath stunning of broilers could be questioned on ethical and bird welfare grounds.

Keywords

animal welfarechickenEEGelectrical stunningfrequencyslaughter
Type
Research Article
Information
Animal Welfare , Volume 15 , Issue 1 , February 2006 , pp. 19 - 24
Copyright
© 2006 Universities Federation for Animal Welfare

References

Anon 1995 The Welfare of Animals (Slaughter or Killing) Regulations. Statutory Instrument 1995 No. 731. Her Majesty's Stationary Office (HMSO): London, UKGoogle Scholar
Bilgili, SF 1992 Electrical stunning of broilers — basic concepts and carcass quality implications: a review. Journal of Applied Poultry Science 1: 135–146CrossRefGoogle Scholar
European Community 1993 Directive 93/119/EC on the protection of animals at the time of slaughter or killing. European Community Official Journal 340: 21–34Google Scholar
Hosmer, DW and Lemeshow, S 2000 Applied Logistic Regression, 2nd Edition. John Wiley & Sons: Chichester, UKCrossRefGoogle Scholar
Ingling, AL and Kuenzel, WJ 1978 Electrical terminology, measurement and units associated with the stunning technique in poultry processing plants. Poultry Science 57: 127–133Google Scholar
Kuenzel, WJ and Wathers, JH 1978 Heart rate, blood pressure, respiration, and brain waves of broilers as affected by electrical stunning and bleed out. Poultry Science 57: 655–659CrossRefGoogle Scholar
McIntyre, CC and Grill, WM 2002 Extracellular stimulation of central neurons: influence of stimulus waveform and frequency on neuronal output. Journal of Neurophysiology 88: 1592–1604CrossRefGoogle ScholarPubMed
Raj, ABM and O'Callaghan, M 2004a Effect of amount and frequency of stunning currents on the electroencephalogram and somatosensory evoked potentials in broilers. Animal Welfare 13: 159–170CrossRefGoogle Scholar
Raj, ABM and O'Callaghan, M 2004b Effects of electrical water bath stunning current frequencies on the spontaneous electroencephalogram and somatosensory evoked potentials in hens. British Poultry Science Journal 45: 230–236Google ScholarPubMed
Raj, ABM, O'Callaghan, M and Hughes, SI 2006b The effects of pulse width of a direct current used in water bath stunning and of slaughter methods on spontaneous electroencephalograms in broilers. Animal Welfare 15: 25–30CrossRefGoogle Scholar
Raj, ABM, O'Callaghan, M and Knowles, T G 2006a The effects of amount and frequency of alternating current used in water bath stunning and of slaughter methods on electroencephalograms in broilers. Animal Welfare 15: 7–18Google Scholar
Sparrey, JM, Kettlewell, PJ, Paice, MER and Whetlor, WC 1993 Development of a constant current waterbath stunner for poultry processing. Journal of Agricultural and Engineering Research 56: 267–274CrossRefGoogle Scholar