How to translate text using browser tools
1 December 2013 APPLYING CLINICALLY PROVEN HUMAN TECHNIQUES FOR CONTRACEPTION AND FERTILITY TO ENDANGERED SPECIES AND ZOO ANIMALS: A REVIEW
Sherman J. Silber, Natalie Barbey, Kathy Lenahan, David Z. Silber
Author Affiliations +
Abstract

Reversible contraception that does not alter natural behavior is a critical need for managing zoo populations. In addition to reversible contraception, other fertility techniques perfected in humans may be useful, such as in vitro fertilization (IVF) or oocyte and embryo banking for endangered species like amphibians and Mexican wolves (Canis lupus baileyi). Furthermore, the genetics of human fertility can give a better understanding of fertility in more exotic species. Collaborations were established to apply human fertility techniques to the captive population. Reversible vasectomy might be one solution for reversible contraception that does not alter behavior. Reversible approaches to vasectomy, avoiding secondary epididymal disruption, were attempted in South American bush dogs (Speothos venaticus), chimpanzees (Pan troglodytes), gorillas (Gorilla gorilla), Przewalski's horse (Equus przewalski poliakov), and Sika deer (Cervus nippon) in a variety of zoos around the world. These techniques were first perfected in > 4,000 humans before attempting them in zoo animals. In vitro fertilization with gestational surrogacy was used to attempt to break the vicious cycle of hand rearing of purebred orangutans, and egg and ovary vitrification in humans have led to successful gamete banking for Mexican wolves and disappearing amphibians. The study of the human Y chromosome has even explained a mechanism of extinction related to global climate change. The best results with vasectomy reversal (normal sperm counts, pregnancy, and live offspring) were obtained when the original vasectomy was performed “open-ended,” so as to avoid pressure-induced epididymal disruption. The attempt at gestational surrogacy for orangutans failed because of severe male infertility and the lack of success with human ovarian hyperstimulation protocols. Vitrification of oocytes is already being employed for the Amphibian Ark Project and for Mexican wolves. Vasectomy can be a reversible contraception option in zoo animals, even in endangered species. Ongoing use of gamete and embryo freezing may salvage vanishing species.

Copyright 2013 by American Association of Zoo Veterinarians
Sherman J. Silber, Natalie Barbey, Kathy Lenahan, and David Z. Silber "APPLYING CLINICALLY PROVEN HUMAN TECHNIQUES FOR CONTRACEPTION AND FERTILITY TO ENDANGERED SPECIES AND ZOO ANIMALS: A REVIEW," Journal of Zoo and Wildlife Medicine 44(4s), (1 December 2013). https://doi.org/10.1638/1042-7260-44.4S.S111
Received: 12 September 2012; Published: 1 December 2013
KEYWORDS
Egg freezing
extinction
gamete banking
sex chromosomes
vasectomy reversal
zoo animals
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top