Position Statements

Humane Mass Depopulation of Domesticated Animals

June 1, 2021

Position

The Canadian Veterinary Medical Association (CVMA) holds that when mass depopulation of domesticated animals is undertaken, methods used must be as humane as achievable in the situation.  Mass depopulation must only be performed by trained personnel who are supervised by persons competent in depopulation and knowledgeable in animal welfare. Methods of restraint and killing must be adapted to the specific circumstances of the situation and the species, size, and age of animal.  CVMA recognizes the potential for emotional impacts on everyone involved in mass depopulation activities and strongly recommends that resources be available to support these individuals.

Summary

  • Mass depopulation methods are employed in situations where large numbers of domesticated animals must be killed for reasons other than slaughter.
  • In all cases, mass depopulation methods must be as humane as possible.  In emergency situations, prevention of worsening welfare may require the use of methods of destruction that would not be chosen in planned depopulations.
    • Unscheduled (emergency) depopulation may occur as a result of animal disease outbreaks, vehicular accidents, or events that result in lack of living space for animals such as unanticipated loss of markets, loss of slaughter capabilities or the inability to transport animals due to infrastructure or weather issues. 
    • Planned depopulation may occur when animals reach the end of a production cycle and slaughter capabilities are not available, or on-farm depopulation is more humane than transport to slaughter.
  • All personnel involved in the mass depopulation of animals must be trained and supervised by persons who are competent in depopulation and animal welfare.  Veterinarians are well positioned to provide leadership in these situations.  
  • Operational procedures must be adapted to the specific circumstances and include detailed preparation, including event logistics, and post event follow up.
  • Mass depopulation procedures can have profound and cumulative emotional impacts on anyone affected by the events.  Access to strategies and support resources are very important to anyone requiring them.

Background

  1. Mass depopulation is the rapid and efficient destruction of a population of domesticated animals for reasons other than slaughter.  It is employed in situations where large numbers of animals must be killed, with minimal compromise to animal welfare.  Mass depopulation protocols must be developed with veterinary consultation and must ensure a smooth, irreversible loss of consciousness with a minimum of stress, fear or pain, followed by death.
  2. Planned mass depopulation may be required in some situations. The CVMA asserts that it must never be used as a substitute for sound management practices when it can be avoided, and that a management plan must be in place to that end. Possible situations include:
    1. end of production cycle where slaughter is not available or on farm killing is more humane, such as with spent hens;
    2. end of research study;
    3. stray or feral animal control where individual euthanasia is not achievable.
  3. Emergency mass depopulation may be necessary in certain situations, and a crisis management plan should be in place.  Examples include:
    1. disaster response;
    2. disease control;
    3. events that result in inability to properly house animals, market loss, supply chain interruption or loss of slaughter capacity;
    4. other types of emergencies where animals must be depopulated for animal welfare reasons.
  4. Animal welfare must be given a high priority in all cases when mass depopulation is to be carried out.  The method chosen needs to allow mass depopulation to be conducted in the most humane manner possible, given the circumstances. Planned depopulations must occur with the highest consideration given to animal welfare because of the ability to prepare ahead of time.  In emergency depopulations, logistics may dictate that a less ideal method be used, yet it still must result in the highest level of animal welfare possible.  Animal welfare should be assessed and monitored by veterinary or other personnel trained in animal welfare.  Logistic factors influencing operational procedures include:
    1. human safety;
    2. available resources;
    3. time constraints;
    4. animal species;
    5. size of animals and size of herd/flock;
    6. age of animals;
    7. housing type or living conditions;
    8. location;
    9. environmental conditions;
    10. PPE;
    11. biosecurity concerns;
    12. legal requirements.
  5. Operational procedures for mass depopulation must be adapted to the specific circumstances and must address the following:
    1. all animals must be cared for in a manner that maintains their welfare until destruction occurs.
    2. humane killing methods employed must be the most appropriate to minimize stress, fear and pain until irreversible loss of consciousness occurs.
    3. when used, animal restraint must be sufficient to facilitate effective humane killing with consideration to animal welfare and operator safety requirements. When restraint is applied, humane killing must follow without delay (1).
  6. Mass depopulation procedures are subject to the applicable legal requirements including occupational health and safety regulations, and federal, provincial and municipal laws and ordinance bylaws of the relevant jurisdiction(s).
  7. In emergency situations, prevention of worsening welfare may require the use of methods of destruction that would not be chosen in scheduled depopulations.  Pre-planning for foreseeable emergency situations will enable successful and humane depopulation events. Livestock producers should only employ depopulation methods recommended by provincial or national regulatory authorities, where applicable.
  8. Mass depopulation for disease purposes may require the use of targeted depopulation of the infected animals on the infected premises and in some cases, animals that are epidemiologically linked to those infected (2,3).
  9. All personnel involved in the humane mass depopulation of animals must be trained and supervised by persons who are competent in humane depopulation.  All aspects of humane mass depopulation require considerable training, practice and expertise. Veterinarians with knowledge and training in animal welfare, animal physiology and production logistics are well positioned to provide leadership in these situations.  The CVMA recommends the development and maintenance of a central repository for information surrounding methods, sources of expertise and information on successes and challenges with respect to mass depopulation.
  10. Mass depopulation procedures can have profound and cumulative emotional impacts on individuals involved.  It is strongly recommended that awareness and education on the risks of emotional trauma be provided for all persons involved in mass depopulations (4,5). These risks can be minimized by action plans that incorporate adequate pre-event planning, appropriate participant selection and education, in-procedure awareness and appropriate post-procedure follow-up.  Competent authorities are advised to incorporate mechanisms to identify and manage impacts of traumatic stress, and individuals are encouraged to seek follow up care as needed.  Education and communication with outside observers and members of the public are also important to provide background and explanations around the challenges, demands and animal welfare considerations that surround mass depopulations (3,6-8).

References

  1. World Organization for Animal Health (OIE). Health standards, Terrestrial animals, Terrestrial Animal Health Code. Killing of animals for disease control purposes. Available from: https://www.oie.int/index.php?id=169&L=0&htmfile=chapitre_aw_killing.htm. Last accessed February 2021.
  2. AVMA Guidelines for the depopulation of animals 2019 edition (2019). Available from: https://www.avma.org/sites/default/files/resources/AVMA-Guidelines-for-the-Depopulation-of-Animals.pdf. Last accessed February 2021.
  3. Appelt M, Sperry J. Stunning and killing cattle humanely and reliably in emergency situations – A comparison between a stunning-only and a stunning and pithing protocol. Can Vet J 2007;48:529-534. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1852607/. Last accessed February 2021.
  4. UK National Audit office. The 2001 Outbreak of Foot and Mouth Disease. REPORT BY THE COMPTROLLER AND AUDITOR GENERAL HC 939 Session 2001-2002. The Stationary Office. Available from: https://www.nao.org.uk/wp-content/uploads/2002/06/0102939.pdf. Last accessed February 2021.
  5. Whiting TL, Marion CR. Perpetration-induced traumatic stress – A risk for veterinarians involved in destruction of healthy animals. Can Vet J. 2011;52(7): 794–796. Available from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3119248/. Last accessed February 2021.
  6. Meuwissen MP, Horst SH, Huirne R, Dijkhuizen AA. A model to estimate the financial consequences of classical swine fever outbreaks: principles and outcomes. Prev Vet Med 1999:42(3), 249-270. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4376735/.  Last accessed February 2021.
  7. UK Cabinet Office. FARMING & FOOD a sustainable future. Report of the Policy Commission on the Future of Farming and Food (2002). Available for download from: https://dera.ioe.ac.uk//10178/. Last accessed February 2021.
  8. Mercer I. Crisis and Opportunity: Devon Foot and Mouth Inquiry: 2001. Devon Books 2002, Halsgrove House Lower Moor Way, Tiverton Devon EX16 6SS.

Additional Reading

  1. American Veterinary Medical Association (AVMA). Guidelines for the Euthanasia of Animals 2020 edition (2020). Available from: https://www.avma.org/sites/default/files/2020-02/Guidelines-on-Euthanasia-2020.pdf. Last accessed February 2021.
  2. Hibi J, Kurosawa A, Watanabe T, Kadowaki H, Watari M, Makita K. Post-traumatic stress disorder in participants of foot-and-mouth disease epidemic control in Miyazaki, Japan, in 2010. J Vet Med Sci 2015;77(8):953–959. Available from: Post-traumatic stress disorder in participants of foot-and-mouth disease epidemic control in Miyazaki, Japan, in 2010 (nih.gov).  Last accessed February 2021.
  3. Thornber PM, Rubira RJ, Styles DK. Humane killing of animals for disease control purposes. Rev Sci Tech 2014;33:303-310. Available from: https://pubmed.ncbi.nlm.nih.gov/25000803/. Last accessed February 2021.
  4. Berg C. The need for monitoring farm animal welfare during mass killing for disease eradication purposes. Anim Welfare. 2012;21:357-361.
  5. McKeegan D. Chapter 17 - Mass depopulation. In: Mench JA, ed. Advances in Poultry Welfare. Woodhead Publishing, 2017:351-372.
  6. Crispin S. M., Roger P. A., O'Hare H. and Binns S. H.The 2001 foot and mouth disease epidemic in the United Kingdom: Animal welfare perspectives. Revue Scientifique Et Technique De L Office International Des Epizooties 2002 ;21(3) : 877-883.
  7. EFSA Panel on Animal Health and Welfare (AHAW), SaxmoseNielson, , S., Alvares, J,, Bicout, D.J., Calistri, P., Depner, K., Drewe, J.A., Garin-Bastui, B., Gonzales Rojas, J.L., Gortazar Schmidt, C. and Michel, V., 2020. Welfare of pigs during killing for purposes other than slaughter. EFSA Journal, 18(7), p.e06195.”