Editorial Type:
Animal Welfare

Evaluation of four methods for inducing death during slaughter of American alligators (Alligator mississippiensis)

Javier G. Nevarez Departments of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803.

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George M. Strain Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803.

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Anderson F. da Cunha Departments of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803.

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Hugues Beaufrère Departments of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803.

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DOI:
https://doi.org/10.2460/ajvr.75.6.536
Volume/Issue:
Volume 75: Issue 6
Online Publication Date:
01 Jun 2014
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Abstract

Objective—To evaluate physical methods for inducing death during the slaughter of American alligators (Alligator mississippiensis).

Animals—24 captive hatched-and-reared American alligators.

Procedures—Baseline electroencephalograms (EEGs) were obtained for awake and anesthetized alligators. Corneal reflex, spontaneous blinking, and EEGs were evaluated after severance of the spinal cord, severance of the spinal cord followed by pithing of the brain, application of a penetrating captive bolt, or application of a nonpenetrating captive bolt (6 alligators/group).

Results—Overall, alligators subjected to spinal cord severance alone differed from those subjected to the other techniques. Spinal cord severance alone resulted in postprocedure EEG power values greater than those in anesthetized alligators, whereas the postprocedure EEG power values were isoelectric for the other 3 techniques. Corneal reflex and spontaneous blinking were absent in all alligators immediately after application of a penetrating or nonpenetrating captive bolt. One of 6 alligators had a corneal reflex up to 1 minute after pithing, but all others within that group had immediate cessation of reflexes after pithing. Mean time to loss of spontaneous blinking and corneal reflex for alligators subjected to spinal cord severance alone was 18 minutes (range, 2 to 37 minutes) and 54 minutes (range, 34 to 99 minutes), respectively.

Conclusions and Clinical Relevance—Spinal cord severance followed by pithing of the brain and application of a penetrating or nonpenetrating captive bolt appeared to be humane and effective techniques for inducing death in American alligators, whereas spinal cord severance alone was not found to be an appropriate method.

Abstract

Objective—To evaluate physical methods for inducing death during the slaughter of American alligators (Alligator mississippiensis).

Animals—24 captive hatched-and-reared American alligators.

Procedures—Baseline electroencephalograms (EEGs) were obtained for awake and anesthetized alligators. Corneal reflex, spontaneous blinking, and EEGs were evaluated after severance of the spinal cord, severance of the spinal cord followed by pithing of the brain, application of a penetrating captive bolt, or application of a nonpenetrating captive bolt (6 alligators/group).

Results—Overall, alligators subjected to spinal cord severance alone differed from those subjected to the other techniques. Spinal cord severance alone resulted in postprocedure EEG power values greater than those in anesthetized alligators, whereas the postprocedure EEG power values were isoelectric for the other 3 techniques. Corneal reflex and spontaneous blinking were absent in all alligators immediately after application of a penetrating or nonpenetrating captive bolt. One of 6 alligators had a corneal reflex up to 1 minute after pithing, but all others within that group had immediate cessation of reflexes after pithing. Mean time to loss of spontaneous blinking and corneal reflex for alligators subjected to spinal cord severance alone was 18 minutes (range, 2 to 37 minutes) and 54 minutes (range, 34 to 99 minutes), respectively.

Conclusions and Clinical Relevance—Spinal cord severance followed by pithing of the brain and application of a penetrating or nonpenetrating captive bolt appeared to be humane and effective techniques for inducing death in American alligators, whereas spinal cord severance alone was not found to be an appropriate method.

Contributor Notes

Dr. Beaufrère's present address is Health Sciences Centre, Ontario Veterinary College, University of Guelph, Guelph, ON N1G 2W1, Canada.

Supported in part by the Louisiana Alligator Council and the Louisiana Department of Wildlife and Fisheries.

Presented in abstract form at the 45th Annual American Association of Zoo Veterinarians Conference, Salt Lake City, September 2013.

Address correspondence to Dr. Nevarez (jnevare@lsu.edu).
Cover American Journal of Veterinary Research
American Journal of Veterinary Research
Publication Date:
01 Jun 2014

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