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. 2019 Jul 1;9(7):407.
doi: 10.3390/ani9070407.

Efficacy of a Novel Mechanical Cervical Dislocation Device in Comparison to Manual Cervical Dislocation in Layer Chickens

Rathnayaka M A S Bandara  1   2 , Stephanie Torrey  1 , Patricia V Turner  3 , Alex Zur Linden  4 , Anna Bolinder  5 , Karen Schwean-Lardner  6 , Tina M Widowski  7
Affiliations

Efficacy of a Novel Mechanical Cervical Dislocation Device in Comparison to Manual Cervical Dislocation in Layer Chickens

Rathnayaka M A S Bandara et al. Animals (Basel). .

Abstract

The main objective of this study was to assess the efficacy of mechanical cervical dislocation using the Koechner Euthanasia Device Model C (KED) in comparison to manual cervical dislocation in layer chickens. Laying hens and/or roosters in three different age groups (12, 27-29, and 65-70 weeks old) were randomly assigned to one of three experimental groups: manual cervical dislocation in conscious birds (CD), manual cervical dislocation in anesthetized birds (aCD), or mechanical cervical dislocation by KED in anesthetized birds (aMCD). Anesthetized birds received an intramuscular dose of 0.3 mg/kg medetomidine and 30 mg/kg of ketamine to achieve clinical anesthesia. A comparison of CD vs. aCD responses confirmed that the anesthetic plane abolished or reduced clonic convulsions, nictitating membrane reflex, tonic convulsions, and cloacal relaxation. Time to loss of the pupillary light reflex (~123 s), and time to cardiac arrest (~172 s) were longer (p < 0.001) in the birds in the aMCD group than aCD (~71 and ~137 s, respectively). Radiographs revealed that the majority of the birds killed by manual cervical dislocation (CD + aCD) had dislocations between the skull and atlas (C1) or between cervical vertebrae C1-C2. The KED resulted in a majority of dislocations at C2-C3. Birds killed by manual cervical dislocation presented more subdural and parenchymal hemorrhage in the brain stem compared to birds killed by KED. Radiographs indicated the presence of fractures in a few birds killed by either method (CD + aCD versus aMCD). Compared to manual CD, KED resulted in less brain trauma and a longer latency to brain death, indicating a lower efficacy of KED as an on-farm killing method.

Keywords: brain stem reflexes; brain trauma; cervical dislocation; on-farm euthanasia; poultry welfare.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Dr. Tina M. Widowski holds the Egg Farmers of Canada Chair in Poultry Welfare.

Figures

Figure 1
Figure 1
(A) Koechner euthanasia device (KED model-C): S—single side blade; D—double angle blade. (B) Application of KED model-C in a 65-week-old anesthetized rooster.
Figure 2
Figure 2
Radiographs of chickens showing cervical dislocations. (A) Luxation between the skull and C1 vertebra in a 65-week-old rooster killed by manual cervical dislocation: Sk—Skull, C1—first cervical vertebra, and C2—second cervical vertebra. (B) Subluxation between C2 and C3 (letter S shows the site of subluxation) in a 65-week-old rooster killed by KED: fractures (F) are present on the articular processes of the C3 vertebra.
See this image and copyright information in PMC

References

    1. Gregory N.G., Wotton S.B. Comparison of neck dislocation and percussion of the head on visual evoked responses in the chicken’s brain. Vet. Rec. 1990;126:570–572. - PubMed
    1. Mason C., Spence J., Bilbe L., Hughes T., Kirkwood J. Methods for dispatching backyard poultry. Vet. Rec. 2009;164:220. doi: 10.1136/vr.164.7.220. - DOI - PubMed
    1. Bader S., Meyer-Kûhling B., Günther R., Breithaupt A., Rautenschlein S., Gruber A.D. Anatomical and histologic pathology induced by cervical dislocation following blunt head trauma for on-farm euthanasia of poultry. J. Appl. Poult. Res. 2014;23:546–556. doi: 10.3382/japr.2014-00977. - DOI
    1. Humane Slaughter Association (HSA) Practical Slaughter of Poultry: A Guide for the Small Producer. Humane Slaughter Association; Wheathampstead, UK: 2004.
    1. European Council European Council Regulation (EC) 1099/2009 of 24 September 2009 on the Protection of Animals at the Time of Killing. [(accessed on 25 January 2019)]; Available online: https://www.gov.uk/government/uploads/system/uploads/attachment_data/fil....

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