Beyond Castration and Culling: Should We Use Non-surgical, Pharmacological Methods to Control the Sexual Behavior and Reproduction of Animals?

  • Clare Palmer
  • Hanne Gervi Pedersen
  • Peter Sandøe


This paper explores ethical issues raised by the application of non-surgical, pharmaceutical fertility control to manage reproductive behaviors in domesticated and wild animal species. We focus on methods that interfere with the effects of GnRH, making animals infertile and significantly suppressing sexual behavior in both sexes. The paper is anchored by considering ethical issues raised by four diverse cases: the use of pharmaceutical fertility control in (a) male slaughter pigs, (b) domesticated stallions and mares, (c) male companion dogs and (d) female white-tailed deer. Ethical concerns explored include animals’ welfare, the possible violation of animals’ rights, including rights to life, reproduction and bodily integrity; and potential concerns about loss of wildness. We compare ethical concerns about pharmaceutical fertility control with alternative strategies for managing animals’ reproductive behavior including (where appropriate) spaying and neutering, sex separation, sex sorting, culling, and doing nothing. The paper concludes that there are some cases where pharmaceutical fertility control is the best ethical choice in current circumstances; but that there are other cases where alternative choices, including doing nothing, would be ethically preferable. This suggests that in ethical terms a case-by-case approach should be taken to the use of pharmaceutical fertility control in animals.


Animal ethics Animal welfare Animal rights Animal fertility control Animal contraception Spaying and neutering 



We are grateful to the participants of the Second Annual Bovay Workshop on Engineering and Applied Ethics, especially Bernice Bovenkerk and Josh Milburn, for comments on this paper. We also want to thank Joyce Briggs and Valerie Benka from the Alliance for Contraception in Cats and Dogs, and the referees for this journal, for their comments and suggestions. Finally we would like to thank Sara V. Kondrup for help with reviewing literature and references.


  1. Aebischer, N. J., Wheatley, C. J., & Rose, H. R. (2014). Factors associated with shooting accuracy and wounding rate of four managed wild deer species in the UK, based on anonymous field records from deer stalkers. PLoS ONE. Scholar
  2. Appleby, M. C., & Sandøe, P. (2002). Philosophical debate on the nature of well-being: Implications for animal welfare. Animal Welfare, 11(3), 283–294.Google Scholar
  3. Benatar, D. (2006). Better never to have been. New York: Oxford University Press.CrossRefGoogle Scholar
  4. Boonin, D. (2003). Robbing PETA to Spay Paul: Do animal rights include reproductive rights? Between the Species, 13(3), 1–8.Google Scholar
  5. Bryan, J. N., Keeler, M. R., Henry, C. J., Bryan, M. E., Hahn, A. W., & Caldwell, C. W. (2007). A population study of neutering status as a risk factor for canine prostate cancer. The Prostate, 67(11), 1174–1181.CrossRefGoogle Scholar
  6. Clutton-Brock, J. (1992). How the wild beasts were tamed. New Scientist, 133(1808), 31–33.Google Scholar
  7. Cochrane, A. (2012). Animal rights without liberation: Applied ethics and human obligations. New York: Columbia University Press.Google Scholar
  8. Cooley, D. M., Beranek, B. C., Schlittler, D. L., Glickman, N. W., Glickman, L. T., & Waters, D. J. (2002). Endogenous gonadal hormone exposure and bone sarcoma risk. Cancer Epidemiology, Biomarkers and Prevention, 11(11), 1434–1440.Google Scholar
  9. De Briyne, N., Berg, C., Blaha, T., & Temple, D. (2016). Pig castration: Will the EU manage to ban pig castration by 2018? Porcine Health Management. Scholar
  10. Ditchkoff, S. S., Welch, E. R., Jr., Lochmiller, R. L., Masters, R. E., Starry, W. R., & Dinkines, W. C. (1998). Wounding rates of white-tailed deer with traditional archery equipment. Proceedings of the Annual Conference of the Southeastern Association of Fish and Wildlife Agencies, 52, 244–248.Google Scholar
  11. Dobson, H. (1985). Effects of chronic treatment with a GnRH agonist on oestrous behaviour and on the secretion of LH and progesterone in the ewe. Theriogenology, 24(1), 1–11.CrossRefGoogle Scholar
  12. Donaldson, S., & Kymlicka, W. (2011). Zoopolis: Towards a political theory of animal rights. New York: Oxford University Press.Google Scholar
  13. Donaldson, S., Kymlicka, W., & Taylor, A. (2014). An interview with Sue Donaldson and Will Kymlicka. Between the Species, 17(1), 140–165.Google Scholar
  14. European Commission. (2017). Alternatives to pig castration. European declaration on alternatives to surgical castration of pigs. Accessed May 30, 2017.
  15. Evans, C. S., DeNicola, A. J., & Warren, R. J. (2016). Comparison of treatment effort for immunocontraceptive vaccines and surgical sterilization in deer. Wildlife Society Bulletin, 40(3), 593–598.CrossRefGoogle Scholar
  16. Evans, J. M., & Sutton, D. J. (1989). The use of hormones, especially progestagens, to control oestrus in bitches. Journal of Reproduction and Fertility (United Kingdom), 39, 163–173.Google Scholar
  17. Field, R. A. (1971). Effect of castration on meat quality and quantity. Journal of Animal Science, 32(5), 849–858.CrossRefGoogle Scholar
  18. Fielding, W., Samuels, D., & Mather, J. (2002). Attitudes and actions of West Indian dog owners towards neutering their animals. Anthrozoös, 15(3), 206–226.CrossRefGoogle Scholar
  19. Francione, G. L., & Charlton, A. E. (2016). The case against pets. Resource document. Aeon. Accessed May 30, 2017.
  20. Fraser, D. (2008). Understanding animal welfare. Acta Veterinaria Scandinavica, 50(Suppl 1), S1. Scholar
  21. German, A. J. (2006). The growing problem of obesity in dogs and cats. The Journal of Nutrition, 136(7), 1940S–1946S.CrossRefGoogle Scholar
  22. Giersing, M., Ladewig, J., & Forkman, B. (2006). Animal welfare aspects of preventing boar taint. Acta Veterinaria Scandinavica. Scholar
  23. Gong, J. G., Campbell, B. K., Bramley, T. A., Gutierrez, C. G., Peters, A. R., & Webb, R. (1996). Suppression in the secretion of follicle-stimulating hormone and luteinizing hormone, and ovarian follicle development in heifers continuously infused with a gonadotropin-releasing hormone agonist. Biology of Reproduction, 55(1), 68–74.CrossRefGoogle Scholar
  24. Gupta, S. K., Gupta, N., Suman, P., Choudhury, S., Prakash, K., Gupta, T., et al. (2011). Zona pellucida-based contraceptive vaccines for human and animal utility. Journal of Reproductive Immunology, 88(2), 240–246.CrossRefGoogle Scholar
  25. Huber-Eicher, B., & Spring, P. (2008). Attitudes of Swiss consumers towards meat from entire or immunocastrated boars: A representative survey. Research in Veterinary Science, 85(3), 625–627.CrossRefGoogle Scholar
  26. Humane Society International. (2017). Street animal welfare. Accessed May 30, 2017.
  27. Jackman, J., & Rowan, A. (2007). Free-roaming dogs in developing countries: The benefits of capture, neuter, and return programs. In D. J. Salem & A. N. Rowan (Eds.), The state of the animals 2007 (pp. 55–78). Washington, DC: Humane Society Press.Google Scholar
  28. Kirkpatrick, J. (1999). Urban deer contraception: The seven stages of grief. In P. Cohn (Ed.), Ethics and wildlife (pp. 205–208). New York: The Edwin Mellen Press.Google Scholar
  29. Kirkpatrick, J., & Turner, J. (1991). Reversible contraception in non-domestic animals. Journal of Zoo and Wildife Medicine, 22(4), 392–408.Google Scholar
  30. Luff, R. M. (1994). The conundrum of castration in the archaeological record: An interpretation of Roman cattle horn-cores from Chelmsford, Essex. International Journal of Osteoarchaeology, 4(3), 171–192.CrossRefGoogle Scholar
  31. Lund, E. M., Armstrong, P. J., Kirk, C. A., & Klausner, J. S. (2006). Prevalence and risk factors for obesity in adult dogs from private US veterinary practices. International Journal of Applied Veterinary Medicine, 4(2), 3–5.Google Scholar
  32. Malmfors, B., & Lundström, K. (1983). Consumer reactions to boar meat—A review. Livestock Production Science, 10(2), 187–196.CrossRefGoogle Scholar
  33. Massei, G., & Miller, L. A. (2013). Nonsurgical fertility control for managing free-roaming dog populations: A review of products and criteria for field applications. Theriogenology, 80(8), 829–838.CrossRefGoogle Scholar
  34. Miller, L. A., Gionfriddo, J. P., Fagerstone, K. A., Rhyan, J. C., & Killian, G. J. (2008). The single-shot GnRH immunocontraceptive vaccine (GonaCon) in white-tailed deer: Comparison of several GnRH preparations. American Journal of Reproductive Immunology, 60(3), 214–223.CrossRefGoogle Scholar
  35. Misdorp, W., Romijn, A., & Hart, A. A. (1990). Feline mammary tumors: A case-control study of hormonal factors. Anticancer Research, 11(5), 1793–1797.Google Scholar
  36. Nussbaum, M. (1999). Sex and social justice. New York: Oxford University Press.Google Scholar
  37. Ostfeld, R. S., Canham, C. D., Oggenfuss, K., Winchcombe, R. J., & Keesing, F. (2006). Climate, deer, rodents, and acorns as determinants of variation in lyme-disease risk. PLoS Biology, 4(6), 1058–1068.CrossRefGoogle Scholar
  38. Palmer, C., Corr, S., & Sandøe, P. (2012). Inconvenient desires: Should we routinely neuter companion animals? Anthrozoos, 25S, 153–172. Scholar
  39. Regan, T. (1983). The case for animal rights. Los Angeles: University of California Press.Google Scholar
  40. Romagnoli, S. (2015). Progestins to control feline reproduction. Historical abuse of high doses and potentially safe use of low doses. Journal of Feline Medicine and Surgery, 17(9), 743–752.CrossRefGoogle Scholar
  41. Sandøe, P., Corr, S., & Palmer, C. (2016). Companion animal ethics. Oxford: Wiley Blackwell.Google Scholar
  42. Schneider, R., Dorn, C. R., & Taylor, D. O. N. (1969). Factors influencing canine mammary cancer development and postsurgical survival. Journal of the National Cancer Institute, 43(6), 1249–1261.Google Scholar
  43. Schulman, M. L., Botha, A. E., Muenscher, S. B., Annandale, C. H., Guthrie, A. J., & Bertschinger, H. J. (2013). Reversibility of the effects of GnRH-vaccination used to suppress reproductive function in mares. Equine Veterinary Journal, 45(1), 111–113.CrossRefGoogle Scholar
  44. Serpell, J. A., & Hsu, Y. A. (2005). Effects of breed, sex, and neuter status on trainability in dogs. Anthrozoös, 18(3), 196–207.CrossRefGoogle Scholar
  45. Squires, E. L., Stevens, W. B., McGlothlin, D. E., & Pickett, B. W. (1979). Effect of an oral progestin on the estrous cycle and fertility of mares. Journal of Animal Science, 49(3), 729–735.CrossRefGoogle Scholar
  46. Stafford, K. J., & Mellor, D. J. (2005). The welfare significance of the castration of cattle: A review. New Zealand Veterinary Journal, 53(5), 271–278.CrossRefGoogle Scholar
  47. Støvring, M., Moe, L., & Glattre, E. (1997). A population-based case-control study of canine mammary tumours and clinical use of medroxyprogesterone acetate. Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), 105(7–12), 590–596.CrossRefGoogle Scholar
  48. Thompson, D. L. (2000). Immunization against GnRH in male species (comparative aspects). Animal Reproduction Science, 60–61, 459–469.CrossRefGoogle Scholar
  49. Torres de la Riva, G., Hart, B. L., Farver, T. B., Oberbauer, A. M., Messam, L. L. M., Willits, N., et al. (2013). Neutering dogs: Effects on joint disorders and cancers in golden retrievers. PLoS ONE. Scholar
  50. Vanhonacker, F., & Verbeke, W. (2011). Consumer response to the possible use of a vaccine method to control boar taint v. Physical piglet castration with anaesthesia: A quantitative study in four European countries. Animal, 5(7), 1107–1118.CrossRefGoogle Scholar
  51. Varner, G. (2011). Environmental ethics, hunting, and the place of animals. In T. Beauchamp & R. G. Frey (Eds.), The Oxford handbook of animal ethics (pp. 855–876). New York: Oxford University Press.CrossRefGoogle Scholar
  52. von Borell, E., Baumgartner, J., Giersing, M., Jäggin, N., Prunier, A., Tuyttens, F. A., et al. (2009). Animal welfare implications of surgical castration and its alternatives in pigs. Animal, 3(11), 1488–1496.CrossRefGoogle Scholar
  53. Webel, S. K., & Squires, E. L. (1982). Control of the oestrous cycle in mares with altrenogest. Journal of Reproduction and Fertility. Supplement, 32, 193–198.Google Scholar
  54. White Buffalo. (n.d.). Deer management techniques. Surgical sterilization. Resource document. Accessed May 30, 2017.

Copyright information

© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  • Clare Palmer
    • 1
  • Hanne Gervi Pedersen
    • 2
  • Peter Sandøe
    • 3
    • 4
  1. 1.Department of PhilosophyTexas A&M UniversityTexasUSA
  2. 2.Department of Veterinary Clinical SciencesUniversity of CopenhagenFrederiksberg CDenmark
  3. 3.Department of Veterinary and Animal SciencesUniversity of CopenhagenFrederiksberg CDenmark
  4. 4.Department of Food and Resource EconomicsUniversity of CopenhagenFrederiksberg CDenmark

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