Applications of emerging technologies to the study and conservation of threatened and endangered species
Budhan Pukazhenthi A C D , Pierre Comizzoli A , Alexander J. Travis B and David E. Wildt AA Smithsonian’s National Zoological Park, Conservation and Research Center, Washington, DC 20008, and Front Royal, VA 22630, USA.
B Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
C Present address: Department of Reproductive Sciences, Smithsonian’s National Zoological Park, 3001 Connecticut Ave, NW, Washington, DC 20008, USA.
D Corresponding author. Email: pukazhenthib@si.edu
Reproduction, Fertility and Development 18(2) 77-90 https://doi.org/10.1071/RD05117
Submitted: 21 September 2005 Accepted: 21 September 2005 Published: 14 December 2005
Abstract
Sustaining viable populations of all wildlife species requires the maintenance of habitat, as well as an understanding of the behaviour and physiology of individual species. Despite substantial efforts, there are thousands of species threatened by extinction, often because of complex factors related to politics, social and environmental conditions and economic needs. When species become critically endangered, ex situ recovery programmes that include reproductive scientists are the usual first line of defence. Despite the potential of reproductive technologies for rapidly increasing numbers in such small populations, there are few examples of success. This is not the result of a failure on the part of the technologies per se, but rather is due to a lack of knowledge about the fundamental biology of the species in question, information essential for allowing reproductive technologies to be effective in the production of offspring. In addition, modern conservation concepts correctly emphasise the importance of maintaining heterozygosity to sustain genetic vigour, thereby limiting the practical usefulness of some procedures (such as nuclear transfer). However, because of the goal of maintaining all extant gene diversity and because, inevitably, many species are (or will become) ‘critically endangered’, it is necessary to explore every avenue for a potential contributory role. There are many ‘emerging technologies’ emanating from the study of livestock and laboratory animals. We predict that a subset of these may have application to the rescue of valuable genes from individual endangered species and eventually to the genetic management of entire populations or species. The present paper reviews the potential candidate techniques and their potential value (and limitations) to the study and conservation of rare wildlife species.
Acknowledgments
This work was supported, in part, by grants from the Friends of the National Zoo (to BP, PC and DEW) and the Morris Animal Foundation and Cornell Feline Health Center (to AJT). PC was supported by a Special Emphasis Career Development award from the National Center for Research Resources of the National Institutes of Health.
Abe, Y. , Hara, K. , Matsumoto, H. , Kobayashi, J. , Sasada, H. , Ekwall, H. , Rodriguez-Martinez, H. , and Sato, E. (2005). Feasibility of a nylon-mesh holder for vitrification of bovine germinal vesicle oocytes in subsequent production of viable blastocysts. Biol. Reprod. 72, 1416–1420.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Cranfield, M. R. , Bavister, B. D. , Boatman, D. E. , Berger, N. G. , Schaffer, S. , Kempske, S. E. , Ialeggio, D. M. , and Smart, J. (2000). Assisted reproduction in the propagation of the endangered lion-tailed macaque (Macaca silenus). Proc. XI Congr. Nacional de Med. Vet., Chile , 1–16.
Dailey, T. , Dale, B. , Cohen, J. , and Munne, S. (1996). Association between nondisjunction and maternal age in meiosis-II human oocytes. Am. J. Hum. Genet. 59, 176–184.
| PubMed |
Dym, M. , and Clermont, Y. (1970). Role of spermatogonia in the repair of seminiferous epithelium following x-irradiation of the rat testis. Am. J. Anat. 128, 265–282.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Hirabayashi, M. , Kato, M. , Ito, J. , and Hochi, S. (2005). Viable rat offspring derived from oocytes intracytoplasmically injected with freeze-dried sperm heads. Zygote 13, 79–85.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Huckins, C. (1978). The morphology and kinetics of spermatogonial degeneration in normal adult rats: an analysis using simplified classification of the germinal epithelium. Anat. Rec. 190, 905–926.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Izadyar, F. , Den Ouden, K. , Stout, T. A. , Stout, J. , and Coret, J. , et al. (2003). Autologous and homologous transplantation of bovine spermatogonial stem cells. Reproduction 126, 765–774.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Loskutoff, N. M. , Bartels, P. , Meintjes, M. , Godke, R. A. , and Schiewe, M. C. (1995). Assisted reproductive technology in nondomestic ungulates: a model approach to preserving and managing genetic diversity. Theriogenology 43, 3–12.
| Crossref | GoogleScholarGoogle Scholar |
Meistrich, M. L. , Hunter, N. R. , Suzuki, N. , Trostle, P. K. , and Withers, H. R. (1978). Gradual regeneration of mouse testicular stem cells after exposure to ionizing radiation. Radiat. Res. 74, 349–362.
| PubMed |
Munson, L. , Gardner, A. , Mason, R. J. , Chassy, L. M. , and Seal, U. S. (2002). Endometrial hyperplasia and mineralization in zoo felids treated with melengestrol acetate contraceptives. Vet. Pathol. 39, 419–427.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Pope, C. E. , Johnson, C. A. , McRae, M. A. , Keller, G. L. , and Dresser, B. L. (1998). Development of embryos produced by intracytoplasmic sperm injection of cat oocytes. Anim. Reprod. Sci. 53, 221–236.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Routray, P. , Suzuki, T. , Strussmann, C. A. , and Takai, R. (2002). Factors affecting the uptake of DMSO by the eggs and embryos of medaka, Oryzias latipes. Theriogenology 58, 1483–1496.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Wildt, D. E. , and Wemmer, C. (1999). Sex and wildlife: the role of reproductive science in conservation. Biodivers. Conserv. 8, 965–976.
| Crossref | GoogleScholarGoogle Scholar |
Wildt, D. E. , Schiewe, M. C. , Schmidt, P. M. , Goodrowe, K. L. , Howard, J. G. , Phillips, L. G. , O’Brien, S. J. , and Bush, M. (1986). Developing animal model systems for embryo technologies in rare and endangered wildlife. Theriogenology 25, 33–51.
| Crossref | GoogleScholarGoogle Scholar |
Wildt, D. E. , Ellis, E. , and Howard, J. G. (2001). Linkage of reproductive sciences: from ‘quick fix’ to ‘integrated’ conservation. J. Reprod. Fertil. Suppl. 57, 295–307.
| PubMed |
Wolf, D. P. , Thormahlen, S. , Ramsey, C. , Yeoman, R. R. , Fanton, J. , and Mitalipov, S. (2004). Use of assisted reproductive technologies in the propagation of rhesus macaque offspring. Biol. Reprod. 71, 486–493.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Wolvekamp, M. C. , Cleary, M. L. , Cox, S. L. , Shaw, J. M. , Jenkin, G. , and Trounson, A. O. (2001). Follicular development in cryopreserved common wombat ovarian tissue xenografted to nude rats. Anim. Reprod. Sci. 65, 135–147.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Yoshizaki, G. , Tago, Y. , Takeuchi, Y. , Sawatari, E. , Kobayashi, T. , and Takeuchi, T. (2005). Green fluorescent protein labeling of primordial germ cells using a nontransgenic method and its application for germ cell transplantation in salmonidae. Biol. Reprod. 73, 88–93.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Young, G. P. , Goldstein, M. , Phillips, D. M. , Sundaram, K. , Gunsalus, G. L. , and Bardin, C. W. (1988). Sertoli cell-only syndrome produced by cold testicular ischemia. Endocrinology 122, 1074–1082.
| PubMed |
Yu, I. , Songsasen, N. , Godke, R. A. , and Leibo, S. P. (2002). Differences among dogs in response of their spermatozoa to cryopreservation using various cooling and warming rates. Cryobiology 44, 62–78.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Zhang, Z. , Renfree, M. B. , and Short, R. V. (2003). Successful intra- and interspecific male germ cell transplantation in the rat. Biol. Reprod. 68, 961–967.
| Crossref | GoogleScholarGoogle Scholar | PubMed |