Applied reproductive technologies and genetic resource banking for amphibian conservation

Reproduction, Fertility and Development

Volumn 21, Issue 6, 2009, Pages 719-737

  Kouba, Andrew J ^a,b   Vance, Carrie K ^a,b  

^a Memphis Zoological Society   (United States)

^b MISSISSIPPI STATE UNIVERSITY   (United States)

Author keywords

Anuran; Cryopreservation; Frog; In vitro fertilisation; Ovulation; Reproduction; Spermatozoa; Toad.

Indexed keywords

AMPHIBIA; ANIMAL HUSBANDRY; ASSISTIVE TECHNOLOGY; BREEDING; CELL SURVIVAL; CONSERVATION BIOLOGY; CRYOPRESERVATION; EPIZOOTIOLOGY; FERTILIZATION IN VITRO; GAMETE; GENETIC RESOURCE; GENETIC VARIABILITY; HORMONAL REGULATION; NONHUMAN; OVULATION; OVULATION INDUCTION; REPRODUCTION; REVIEW; SPECIES; SPECIES DIFFERENCE; SPERMATOZOON; SPERMATOZOON MOTILITY; WILD TYPE; ANIMAL; ENVIRONMENTAL PROTECTION; FEMALE; HEALTH CARE FACILITY; INFERTILITY THERAPY; MALE; OOCYTE; PHYSIOLOGY; POPULATION DENSITY; PROGRAM DEVELOPMENT; SPECIES EXTINCTION; SPERM PRESERVATION; SPERMATOGENESIS; TISSUE PRESERVATION;

AMPHIBIA; ANIMALIA; ANURA;

FERTILITY PROMOTING AGENT;

AMPHIBIANS; ANIMALS; BIOLOGICAL SPECIMEN BANKS; BREEDING; CONSERVATION OF NATURAL RESOURCES; CRYOPRESERVATION; EXTINCTION, BIOLOGICAL; FEMALE; FERTILITY AGENTS; MALE; OOCYTES; OVULATION; POPULATION DENSITY; PROGRAM DEVELOPMENT; REPRODUCTIVE TECHNIQUES; SEMEN PRESERVATION; SPERM BANKS; SPERMATOGENESIS; TISSUE PRESERVATION;

EID: 70149111277     PISSN: 10313613     EISSN: None     Source Type: Journal    
DOI: 10.1071/RD09038     Document Type: Review

References (141)

1. Alexander, M. A., and Eischeid, J. K. (2001 ). Climate variability in regions of amphibian declines. Conserv. Biol. 15(4), 930-942. doi:10.1046/J.1523-1739.2001.015004930.X
2. Alford, R. A., Dixon, P. M., and Pechmann, J. H. K. (2001 ). Global amphibian population declines. Nature 411, 499-500. doi:10.1038/35087658
3. Arimura, A., Vilchez-Martinez, J. A., Coy, D. H., Hirotsu, Y, and Schally, A. V (1974). [D-Ala6, Des-Gly-NH210]-LH-RH-ethylamide: a new analogue with unusually high LH-RH/FSH-RH activity. Endocrinology 95, 1174-1177.
4. Bainbridge, D. R. J., and Jabbour, H. N. (1998). Potential of assisted breeding techniques for the conservation of endangered mammalian species in captivity: a review. Vet. Rec. 143, 159-168.
5. Barton, H. L., and Guttman, S. I. (1972). Low temperature preservation of toad spermatozoa (Genus Bufo). Tex. J Sci. 23, 363-370.
6. Beesley, S. G., Costanzo, J. P., and Richard, E. L., Jr (1998). Cryopreservation of spermatozoa from freeze-tolerant and -intolerant anurans. Cryobiology 37, 155-162. doi:10.1006/CRYO.1998.2119
7. Bellerby, C. W. (1934). A rapid test for the diagnosis of pregnancy. Nature 133, 494-495. doi:10.1038/133494B0
8. Bennet, P. M. (2001). Establishing animal germplasm resource banks for wildlife conservation: genetic, population and evolutionary aspects. In 'Cryobanking the Genetic Resource: Wildlife Conservation for the Future?'. (Eds P. F. Watson and W. V. Holt.) pp. 47-67. (Taylor and Francis: London and New York.)
9. Biesinger, D. I., and Miller, D. F. (1952). Seasonal and hormone-induced changes in the testes of Rana pipiens. Ohio J Sci. 52(3), 169-175.
10. Blaustein, A. R., and Belden, L. K. (2005). Ultraviolet radiation. In 'Amphibian Declines: Conservation Status of United States Species'. (Ed. M. Lannoo.) pp. 87-88. (University of California Press: Berkeley, LA.)
11. Blaustein, A. R., Kiesecker, X M., Chivers, D. P., and Anthony, R. G. (1997). Ambient UV-B radiation causes deformities in amphibian embryos. Proc. Natl Acad. Sci. USA 94(25), 13735-13737. doi:10.1073/PNAS.94.25.13735
12. Blesbois, E., Seigneurin, F., Grasseau, I., Limouzin, C., Besnard, J., Gourichon, D., Coquerelle, G., Rault, P., and Tixier-Boichard, M. (2007). Semen cryopreservation for ex situ management of genetic diversity in chicken: creation of the French avian cryobank. Poult. Sci. 86(3), 555-564. (Pubitemid 47581095)
13. Bradley, G. A., Rosen, P. C., Sredl, M. J., Jones, T. R., and Longcore, J. E. (2002). Chytridiomycosis in native Arizona frogs. J. Wildl. Dis. 38(1), 206-212.
14. Braz, S. V., Fernandes, A. P., and Báo, S.N. (2004). An ultrastructural study of sperm of the genus Bufo (Amphibia, Anura, Bufonidae). J. Submicrosc. Cytol. Pathol. 36(3-4), 257-262. (Pubitemid 40545378)
15. Bridges, C. M., and Semlitsch, R. D. (2005a). Xenobiotics. In 'Amphibian Declines: Conservation Status of United States Species'. (Ed. M. Lannoo.) pp. 89-92. (University of California Press: Berkeley, LA.)
16. Bridges, C. M., and Semlitsch, R. D. (2005i). Variation in pesticide tolerance. In 'Amphibian Declines: Conservation Status of United States Species'. (Ed. M. Lannoo.) pp. 93-95. (University of California Press: Berkeley, LA.)
17. Briggs, R., and King, X X (1952). Transplantation of Living nuclei from blástula cells into enucleated frogs eggs. Proc. Natl. Acad. Sci. USA 38, 455-463. doi10.1073/PNAS.38.5.455
18. Browne, R. K., Clulow, J., Mahony, M., and Clark, A. (1998). Successful recovery of motility and fertility of cryopreserved cane toad (Bufo marinus) sperm. Cryobiology 37, 339-345. doi:10.1006/CRYO.1998.2129 (Pubitemid 128415245)
19. Browne, R. K., Clulow, J., and Mahony, M. (2001 ). Short-term storage of cane toad (Bufo marinus) gametes. Reproduction 111, 167-173. doi:10.1530/ REP.0.1210167
20. Browne, R. K., Clulow, J., and Mahony, M. (2002a). The effect of saccharides on the post-thaw recovery of cane toad (Bufo marinus) spermatozoa. Cryo Letters 23, 121-128. (Pubitemid 34548624)
21. Browne, R. K., Mahony, M., and Clulow, J. (2002&). The short-term storage and cryopreservation of spermatozoa from hylid and myobatrachid frogs. Cryo Letters 23, 129-136.
22. Browne, R. K., Davis, J., Pomering, M., and Clulow, J. (2002c). Storage of cane toad (Bufo marinus) sperm for 6 days at 0°C with subsequent cryopreservation. Reprod. Fertil. Dev. 14, 267-273. doi:10.1071/ RD01045
23. Browne, R. K., Mahony, M., and Clulow, J. (2002d). A comparison of sucrose, saline, and saline with egg-yolk diluents on the cryopreservation of cane toad (Bufo marinus) sperm. Cryobiology 44, 251-257. doi:10.1016/S0011- 2240(02)00031-7
24. Browne, R. K., Li, H., Seratt, J., and Kouba, A. J. (2006a). Progesterone improves the number and quality of hormone-induced Fowler toad (Bufo fowleri) oocytes. J. Reprod. Biol. Endocrinol. 4, 3. doi:10.1186/1477-7827-4-3 (Pubitemid 43264331)
25. Browne, R. K., Seratt, J., Vance, C. K., and Kouba, A. J. (2006b). Hormonal priming, induction of ovulation and in vitro fertilization of the endangered Wyoming toad (Bufo baxteri). J. Reprod. Biol. Endocrinol. 4, 34. doi:10.1186/1477-7827-4-34 (Pubitemid 44165192)
26. Brun, R. (1975). Oocyte maturation in vitro: contribution of the oviduct to total maturation in Xenopus laevis. Experientia 31(11), 1275-1276. doi:10.1007/BF01945777
27. Buchholz, D. R., Fu, L., and Shi, Y B. (2004). Cryopreservation of Xenopus transgenic lines. Mol. Reprod. Dev. 67(1), 65-69. doi:10.1002/ MRD.20005
28. Cabada, M. O. (1975). Sperm concentration and fertilization rate in Bufo arenarum (Amphibian: Anura). J. Exp. Biol. 62, 481-486.
29. Carey, C., Heyer, W. R., Wilkinson, J., Alford, R. A., Arntzen, J. W, et al. (2001). Amphibian declines and environmental change: use of remotesensing data to identify environmental correlates. Conserv. Biol. 15(4), 903-913. doi:10.1046/J.1523-1739.2001.015004903.X (Pubitemid 32706831)
30. Clulow, J., Mahony, M., Browne, R., Pomering, M., and Clark, A. (1999). Applications of assisted reproductive technologies (ART) to endangered amphibian species. In 'Declines and Disappearance of Australian Frogs'. (Ed. A. Campbell.) pp. 219-225. (Environment Australia: Canberra.)
31. Comizzoli, P., Mermillod, P., and Maugut, R. (2000). Reproductive biotechnologies for endangered mammalian species. Reprod. Nutr. Dev. 40, 493-504. doi:10.1051/RND:2000113
32. Costanzo, J. P., Mugnano, J. A., Wehrheim, H. M., and Richard, E. L., Jr (1998). Osmotic and freezing tolerance in spermatozoa of freeze-tolerant and -intolerant frogs. Am. J. Physiol. 275, 713-719.
33. Crump, D., Lean, D., and Trudeau, V. L. (2001). Octylphenol and UV-B radiation alter larval development and hypothalamic expression in the leopard frog (Ranapipiens). Environ. Health Perspect. 110(3), 277-284.
34. Curry, M. R. (2000). Cryopreservation of semen from domestic livestock. Rev. Reprod. 5, 46-52. doi:10.1530/ROR.0.0050046
35. de Meeus, J., Prugnolle, F., and Agnew, P. (2007). Asexual reproduction: genetics and evolutionary aspects. Cell Mol. Life Sci. 64, 1355-1372. doi:10.1007/S00018-007-6515-2 (Pubitemid 46889229)
36. Di Berardino, M. A. (2006). Origin and progress of nuclear transfer in nonmammalian animals. Methods Mol. Biol. 348, 3-31. doi:10.1007/978-1-59745-154- 3-l
37. Dong, Q., Huang, C., Eudeline, B., and Tiersch, T. R. (2005). Systematic factor optimization for cryopreservation of shipped sperm samples of diploid Pacific oysters, Crassostrea gigas. Cryobiology 51, 176-197. doi:10.1016/XCRYOBIOL.2005.06.007 (Pubitemid 41393061)
38. Dreitz, V. J. (2006). Issues in species recovery: an example based on the Wyoming toad. Bioscience 56(9), 765-771. doi:10.1641/0006-3568(2006)56[765: IISRAE]2.0.CO;2
39. Duellman, W. E., and Trueb, L. (1986). Enemies and defense. In 'Biology of Amphibians', pp. 241-260. (The Johns-Hopkins University Press: Baltimore.)
40. Easley, K. A., Culley, D. D., Jr, Horseman, N. D., and Penkala, J. E. (1979). Environmental influences on hormonally induced spermiation of the bullfrog, Rana catesbeiana. J Exp. Zool. 207, 407-416. doi:10.1002/ JEZ.1402070309
41. Edwards, D. L., Mahony, M. J., and Clulow, J. (2004). Effect of sperm concentration, medium osmolality and oocyte storage on artificial fertilization success in a myobatrachid frog (Limnodynastes tasmaniensis). Reprod. Fertil. Dev. 16, 347-354. doi:10.1071/RD02079
42. Elinson, R. P. (1986). Fertilization in amphibians: the ancestry of the block to polyspermy. Int. Rev. Cytol. 101, 59-100. doi:10.1016/S0074-7696(08) 60246-6
43. Elsdale, T. R., Gurdon, J. B., and Fischberg, M. (1960). A description of the technique for nuclear transplantation in Xenopus laevis. J Embryol. Exp. Morphol. 8, 437-444.
44. Fitzsimmons, C., McLaughlin, E. A., Mahony, M. J., and Clulow, J. (2007). Optimisation of handling, activation and assessment procedures for Bufo marinus spermatozoa. Reprod. Fertil. Dev. 19, 594-601. doi:10.1071/ RD06124 (Pubitemid 46733598)
45. Fulton, J. E. (2006). Avian genetic stock preservation: an industry perspective. Poult. Sci. 85(2), 227-231.
46. Galli-Mainini, C. (1947). Pregnancy test using the male toad. J. Clin. Endocrinol. Metab. 1, 653-658.
47. Galli-Mainini, C. (1948). Pregnancy test using the male Batrachia. J. Am. Med. Assoc. 138, 121.
48. Gascon, C., Collins, J. P., Moore, R. D., Church, D. R., McKay, J. E., and Mendelson, J. R., Ill (Eds) (2007). 'Amphibian Conservation Action Plan.' (IUCN/SSC Amphibian Specialist Group: Gland, Switzerland and Cambridge, UK.)
49. George, J. M., Smita, M., Kadalmani, B., Girija, R., Oommen, O. V., and Akbarsha, M. A. (2005). Contribution of the secretory material of caecilian (Amphibian: Gymnophiona) male mullerian gland to motility of sperm: a study in Uraeotyphlus narayani. J. Morphol. 263, 227-237. doi:10.1002/.TMOR.10300 (Pubitemid 40263237)
50. Goncharov, B. F., Shubravy, O. I., Serbinova, I. A., and Uteshev, V. K. (1989). The USSR programme for breeding amphibians, including rare and endangered species. Int. Zoo Yearb. 28, 10-21. doi:10.1111/J.1748-1090.1988. TB01009.X
51. Graham, L. H., Byers, A. P., Armstrong, D. L., Loskutoff, N. M., Swanson, W. F., Wildt, D. E., and Brown, J. L. (2006). Natural and gonadotropin-induced ovarian activity in tigers (Panthera tigris) assessed by faecal steroid analyses. Gen. Comp. Endocrinol. 147(3), 362-370. doi:10.1016/XYGCEN.2006.02.008
52. Green, D. M. (2005). Biology of amphibian declines. In 'Amphibian Declines: Conservation Status of United States Species'. (Ed. M. Lannoo.) pp. 28-33. (University of California Press: Berkeley, LA.)
53. Griffiths, R. A., and Pavajeau, L. (2008). Captive breeding, reintroduction, and the conservation of amphibians. Conserv. Biol. 22(4), 852-861. doi:10.1111/J.1523-1739.2008.00967.X
54. Guenther, J. F., Seki, S., Kleinhans, F. W., Edashige, K., Roberts, D. M., and Mazur, P. (2006). Extra- and intra-cellular ice formation in stage I and II Xenopus laevis oocytes. Cryobiology 52, 401-416. doi:10.1016/ XCRYOBIOL.2006.02.002
55. Hagedorn, M., Peterson, A., Mazur, P., and Kleinhans, F. W. (2004). High ice-nucleation temperature of zebrafish embryos: slow-freezing is not an option. Cryobiology 49, 181-189. doi:10.1016/XCRYOBIOL. 2004.07.001 (Pubitemid 39194680)
56. Hakkinen, J., Pasanen, S., and Kukkonen, J. V. (2001). The effects of solar UV-B radiation on embryonic mortality and development in three boreal anurans (Rana temporaria, Rana arvalis and Bufo bufo). Chemosphere 44(3), 441-446. doi:10.1016/S0045-6535(00)00295-2 (Pubitemid 32594958)
57. Hayes, T. B., Collins, A., Lee, M., Mendoza, M., Noriega, N., Stuart, A. A., and Vonk, A. (2002). Hermaphroditic, demasculinised frogs after exposure to the herbicide atrazine at low ecologically relevant doses. Proc. Natl Acad. Sci. USA 99(8), 5476-5480. doi:10.1073/PNAS.082121499 (Pubitemid 34411573)
58. Hirsch, N., Zimmerman, L. B., and Grainger, R. M. (2002). Xenopus, the next generation: X. tropicalis genetics and genomics. Dev. Dyn. 225, 422-433. doi:10.1002/DVDY.10178 (Pubitemid 35429726)
59. Hodges, J. K. (2001). Reproductive technologies necessary for successful application of genetic resource banking. In 'Cryobanking the Genetic Resource: Wildlife Conservation for the Future?'. (Eds P. F. Watson and W V Holt.) pp. 85-112. (Taylor and Francis: London and New York.)
60. Hollinger, J. G., and Corton, G. L. (1980). Artificial fertilisation of gametes from the South African clawed frog, Xenopus laevis. Gamete Res. 3, 45-57. doi:10.1002/MRD.1120030106
61. Holt, W. V. (2001). Genetic resource banking and maintaining biodiversity. In 'Cryobanking the Genetic Resource: Wildlife Conservation for the Future?'. (Eds P. F Watson and W. V. Holt.) pp. 9-20. (Taylor and Francis: London and New York.)
62. Holt, W. V., Bennett, P. M., and Volobouev, V. (1996). Genetic resource banks in wildlife conservation. J Zool. (Lond.) 238, 531-544. (Pubitemid 2626146)
63. Holt, W. V., Pickard, A. R., and Prather, R. S. (2004). Wildlife conservation and reproductive cloning. Reproduction 127(3), 317-324. doi:10.1530/ REP.1.00074
64. Howard, J. G., and Wildt, D. E. (2009). Approaches and efficacy of artificial insemination in felids and mustelids. Theriogenology 71(1), 130-148. doi:10.1016/XXHERIOGENOLOGY2008.09.046
65. Howard, J., Marinari, P. E., and Wildt, D. E. (2003). Black-footed ferret: model for assisted reproductive technologies contributing to in situ conservation. In 'Reproductive Science and Integrated Conservation'. (Eds W. V. Holt, A. R. Pickard, J. C. Rodger and D. E. Wildt.) pp. 249-266. (Cambridge University Press: Cambridge.)
66. Iimori, E., D'Occhio, M. J., Lisle, A. T., and Johnston, S. D. (2005). Testosterone secretion and pharmacological spermatozoal recovery in the cane toad. ,4mm. Reprod. Sci. 90, 163-173. doi:10.1016/XANIREPROSCI. 2005.01.010 (Pubitemid 41562187)
67. Ishihara, K., Hosono, J., Kanatani, H., and Katagari, C. (1984). Toad egg jelly as a source of divalent cations essential for fertilisation. Dev. Biol. 105(2), 435-442. doi:10.1016/0012-1606(84)90300-2 (Pubitemid 14021994)
68. IUCN, Conservation International, and NatareServe (2006). 'Global Amphibian Assessment.' Available at: www.globalamphibians.org [Accessed 4 May 2006].
69. Johnson, C. J., Vance, C. K., Roth, T. L., and Kouba, A. J. (2002). Oviposicion and ultrasound monitoring of American toads (Bufo americanus) treated with exogenous hormones. In 'Proceedings of the American Association of Zoo Veterinarians Meeting, Milwaukee, WI, 5-10 October', pp. 299-301.
70. Kaurova, S. A., Uteshev, V. K., Chekurova, N. R., and Gakhova, E. N. (1997). Cryopreservation of testis of frog Rana temporaria. Infusionsther. Transfusiosmed. 24, 378.
71. Kawamoto, T., Narita, T., Isowa, K., Aoki, H., Hayashi, M., Komaru, A., and Ohta, H. (2007). Effects of cryopreservation methods on postthaw motility of spermatozoa from the Japanese pearl oyster, Pinctada fucata martensii. Cryobiology 54, 19-26. doi:10.1016/XCRYOBIOL. 2006.10.190
72. Kiesecker, J. M., Blaustein, A. R., and Beiden, L. K. (2001). Complex causes of amphibian population declines. Nature 410(6829), 681-684. doi:10.1038/35070552 (Pubitemid 32290352)
73. Kikyo, N., and Wolffe, A. P. (2002). Reprogramming nuclei: insights from cloning, nuclear transfer and heterokaryons. J. Cell Sci. 113, 11-20. (Pubitemid 30066329)
74. King, T. J. (1966). Nuclear transplantation in amphibian. In 'Methods in Cell Physiology. Vol. 2'. (Ed. D. M. Prescott.) pp. 1-36. (Academic Press: New York.)
75. Kleinhans, F. W., Guenther, J. F., Roberts, D. M., and Mazur, P. (2006). Analysis of intracellular ice nucleation in Xenopus oocytes by differential scanning calorimetry. Cryobiology 52, 128-138. doi:10.1016/ J.CRYOBIOL.2005.10. 008
76. Komen, H., and Thorgaard, G. H. (2007). Androgenesis, gynogenesis and the production of clones in fish: a review. Aquaculture 269(1-4), 150-173. doi:10.1016/J.AQUACULTURE.2007.05.009 (Pubitemid 47058559)
77. Kouba, A. J., Vance, C. K., and Willis, E. (2009). Artificial fertilisation for amphibian conservation: current knowledge and future considerations. Theriogenology 71, 214-227. doi:10.1016/XTHERIOGENOLOGY. 2008.09.055
78. Kouba, A. J., Vance, C. K., Frommeyer, M. A., and Roth, T. L. (2003). Structural and functional aspects of Bufo americanus spermatozoa: effects of inactivation and reactivation. J. Exp. Zool. 295A, 172-182. doi:10.1002/ JEZ.A.10192
79. Krapf, D., Visconti, P. E., Arranz, S. E., and Cabada, M. O. (2007). Egg water from the amphibian Bufo arenarum induces capacitation-like changes in homologous spermatozoa. Dev. Biol. 306, 516-524. doi:10.1016/ XYDBIO.2007.03.030 (Pubitemid 46881067)
80. Kurian, T., and Saidapur, S. K. (1982). Comparative effects of hCG & PMSG on spermatogenesis, Leydig cells & thump pads of the frog, Rana tigrina (Daud), during post-breeding regression. Indian J. Exp. Biol. 20, 577-581. (Pubitemid 13228962)
81. Lahnsteiner, F., Berger, B., Horvath, A., Urbanyi, B., and Weismann, T. (2000). Cryopreservation of spermatozoa in cyprinid fishes. Theriogenology 54, 1477-1498. doi:10.1016/S0093-691X(00)00469-6
82. Lam, T. J. (1982). Applications of endocrinology to fish culture. Can. J. Fish. Aquat. Sci. 39, 111-137. doi:10.1139/F82-013
83. Lam, T. J., Pandey, S., and Hoar, W S. (1975). Induction of ovulation in goldfish by synthetic luteinizing hormone-releasing hormone (LH-RH). Can. J Zool. 53(8), 1189-1192. doi:10.1139/ Z75-140
84. Lentini, A. (2002). Reproduction. In 'Puerto Rican Crested Toad Husbandry Manual'. American Association of Zoos and Aquariums (AZA) Amphibian Taxon Advisory Group (www.aza.org).
85. Long, J. A. (2006). Avian semen cryopreservation: what are the biological challenges? Poult. Sci. 85(2), 232-236.
86. Luyet, B. J., and Hodapp, E. L. (1938). Revival of frog's spermatozoa vitrified in liquid air. Proc. Soc. Exp. Biol. Med. 39, 433-434.
87. Masui, Y., and Clarke, H. J. (1979). Oocyte maturation. Int. Rev. Cytol. 57, 185-282. doi:10.1016/S0074-7696(08)61464-3
88. McKinnell, R. G., Picciano, D. J., and Kriegg, R. E. (1976). Fertilisation and development of frog eggs after repeated spermiation induced by human chorionic gonadotropin. Lab Anim. Sci. 26(6), 932-935.
89. Michael, S. F., and Jones, C. (2004). Cryopreservation of spermatozoa of the terrestrial Puerto Rican frog, Eleutherodactylus coqui. Cryobiology 48, 90-94. doi:10.1016/XCRYOBIOL.2003.11.001
90. Moore, J. A. (1955). Abnormal combinations of nuclear and cytoplasmic systems in frogs and toads. Adv. Genet. 1,139-182. doi:10.1016/S0065-2660(08) 60095-4
91. Mugnano, J. A., Costanzo, J. P., Beesley, S. G., and Richard, E. R., Jr (1998). Evaluation of glycerol and dimethyl sulphoxide for the cryopreservation of spermatozoa from the wood frog (Rana sylvatica). Cryo Letters 19, 249-254.
92. Nace, G. W., Richards, C. M., and Asher, j. H. (1970). Parthenogenesis and genetic variability. I. Linkage and inbreeding estimations in the frog, Rana pipiens. Genetics 66, 349-368.
93. Norris, D. O. (2007). III. Tropic hormones of the adenohypophysis. In 'Vetebrate Endocrinology'. 4th edn. (Ed. D. O. Norris.) pp. 125-140. (Academic Press: San Diego.)
94. Obringer, A. R., O'Brien, J. K., Saunders, R. L., Yamamoto, K., Kikuyama, S., and Roth, T. L. (2000). Characterisation of the spermiation response, luteinizing hormone release and sperm quality in the American toad (Bufo americanus) and the endangered Wyoming toad (Bufo baxteri). Reprod. Fertil. Dev. 12, 51-58. doi:10.1071/RD00056 (Pubitemid 32009801)
95. Olson, J. H., and Chandler, D. E. (1999). Xenopus laevis egg jelly contains small proteins that are essential to fertilisation. Dev. Biol. 210, 401-410. doi:10.1006/DBIO.1999.9281
96. Pessier, A. P., Nichols, D. K., Longcore, J. E., and Fuller, M. S. (1999). Cutaneous chytridiomycosis in poison dart frogs (Dendrobates spp.) and White's tree frog (Litoria caerulea). J Vet. Diagnostic Investigation 11, 194-199.
97. Folge, C., Smith, A. U., and Parkes, A. S. (1949). Revival of spermatozoa after vitrification and dehydration at low temperatures. Nature 164, 666-676. doi:10.1038/164666A0
98. Pozzi, A. G., Rosemblit, C., and Ceballos, N. R. (2006). Effect of human gonadotropins on spermiation and androgen biosynthesis in the testis of the toad Bufo arenarum (Amphibia, Anura). J Exp. Zool. 305A(1), 96-102. doi:10.1002/JEZ.A.254
99. Prather, R. S., Barnes, F. L., Sims, M. M., Robl, J. M., Eyestone, W. H., and First, N. L. (1987). Nuclear transplantation in the bovine embryo: assessment of donor nuclei and recipient oocyte. Biol. Reprod. 37(4), 859-866. doi:10.1095/BIOLREPROD37.4.859
100. Pukazhenthi, B., and Wildt, D. (2004). Which reproductive technologies are most relevant to studying, managing and conserving wildlife? Reprod. Fértil. Dev. 16, 33-46. doi:10.1071/RD03076 (Pubitemid 37541089)
101. Rabb, G. B. (1999). The amphibian crisis. In 'Proceedings of the Seventh World Conference on Breeding Endangered Species: Linking Zoos and Field Research to Advance Conservation'. (Eds T. L. Roth, W F. Swanson and L. K. Blattman.) pp. 23-30. (Cincinnati Zoo and Botanical Garden: Cincinnati.)
102. Reaser, J. K., and Blaustein, A. (2005). Repercussions of global change. In 'Amphibian Declines: Conservation Status of United States Species'. (Ed. M. Lannoo.) pp. 60-63. (University of California Press: Berkeley, LA.)
103. Roth, T. L., and Obringer, A. R. (2003). Reproductive research and the Worldwide amphibian extinction crisis. In 'Reproductive Science and Integrated Conservation'. (Eds W V Holt, A. R. Pickard, X C. Rodger and D. E. Wildt.) pp. 359-374. (Cambridge University Press: Cambridge.)
104. Rowson, A. D., Obringer, A. R., and Roth, T. L. (2001). Non-invasive treatments of lutaenizing hormone-releasing hormone for inducing spermiation in American (Bufo americanus) and Gulf coast (Bufo valliceps) toads. Zoo Biol. 20, 63-74. doi:10.1002/ZOO.1007 (Pubitemid 33299566)
105. Rugh, R. (1965). 'Experimental Embryology: Techniques and Procedures.' 3rd edn. (Burgess Publishing Co.: Minneapolis.)
106. Ryder, O. A., McLaren, A., Brenner, S., Zhang, Y. P., and Benirschke, K. (2000). DNA banks for endangered species. Science 288, 275-277. doi:10.1126/SCIENCE.288.5464.275
107. Sargent, M. G., and Mohun, T. J. (2005). Cryopreservation of sperm of Xenopus laevis and Xenopus tropicalis. Genesis 41, 41-46. doi:10.1002/ GENE.20092
108. Schuetz, A. W. (1971). In vitro induction of ovulation and oocyte maturation in Rana pipiens ovarian follicles: effects of steroidal and non-steroidal hormones. J Exp. Zool. 178, 377-385. doi:10.1002/JEZ.1401780313
109. Schultz, T. W., and Dawson, D. A. (2003). Housing and husbandry of Xenopus for oocyte production. Lab. Anim. 32, 34-39. doi:10.1038/ LABAN0203-34
110. Shapiro, H. A., and Zwarenstein, H. (1934). A rapid test for pregnancy on Xenopus laevis. Nature 133, 762. doi:10.1038/133762A0
111. Shaver, J. R. (1953). Studies on the initiation of cleavage in the frog egg. J. Exp. Zool. 122, 169-192. doi:10.1002/JEZ.1401220110
112. Signoret, J., Briggs, R., and Humphrey, R. R. (1962). Nuclear transplantation in the axolotl. Dev. Biol. 4, 134-164. doi:10.1016/0012-1606(62) 90037-4
113. Soule, M. E. (1991). Conservation tactics for a constant crisis. Science 253, 744-750. doi:10.1126/SCIENCE.253.5021.744
114. Sparling, D. W., Fellers, G. M., and McConnell, L. L. (2001). Pesticides and amphibian population declines in California, USA. Environ. Toxicol. Chem. 20, 1591-1595. doi:10.1897/1551-5028(2001)020 <1591:PAAPDI>2.0.CO;2 (Pubitemid 32550022)
115. Spencer, B. (2002). Reproduction. In 'Puerto Rican Crested Toad Husbandry Manual'. American Association of Zoos and Aquariums (AZA) Amphibian Taxon Advisory Group (www.aza.org).
116. Stallard, R. F. (2001). Possible environmental factors underlying amphibian decline in eastern Puerto Rico: analysis of U.S. government data archives. Conserv. Biol. 15(4), 943-953. doi:10.1046/J.1523-1739.2001. 015004943.X
117. Subcommittee on Amphibian Standards (1996). 'Amphibians: Guidelines for the Breeding, Care, and Management of Laboratory Animals.' (Eds Committee on Standards, National Research Council.) (National Academy Press Inc.: Washington, DC.) Available at: http://books.nap. edu/html/amphibian.
118. Swanson, W. F. (2006). Application of assisted reproduction for population management in felids: the potential and reality for conservation of small cats. Theriogenology 66, 49-58. doi:10.1016/XTHERIOGENOLOGY. 2006.03.024
119. Swanson, W. F., Horohov, D. W., and Godke, R. A. (1995). Production of exogenous gonadotropin-neutralising immunoglobulins in cats following repeated eCG/hCG treatment and relevance for assisted reproduction in felids. J. Reprod. Fértil. 105, 35-41. doi:10.1530/JRF.0. 1050035
120. Swanson, W. F., Wolfe, B. A., Brown, J. L., Martin-Jimenez, T., Riviere, J. E., and Roth, T. L. (1997). Pharmacokinetics and ovarian-stimulatory effects of equine and human chorionic gonadotropins administered singly and in combination in the domestic cat. Biol. Reprod. 57, 295-302. doi:10.1095/ BIOLREPROD57.2.295 (Pubitemid 27343687)
121. Szymanski, D. C., Gist, D. H., and Roth, T. L. (2006). Anuran gender identification by faecal steroid analysis. Zoo Biol. 25, 35-46. doi:10.1002/ ZOO.20077
122. Tiersch, T. R., Yang, H., Jenkins, J. A., and Dong, Q. (2007). Sperm cryopreservation in fish and shellfish. Soc. Reprod. Fertil. Suppl. 65, 493-508.
123. Toro, E., and Michael, S. F. (2004). In vitro fertilisation and artificial activation of eggs of the direct developing anuran Eleutherodactylus coqui. J Reprod. Biol. Endocrinol. 2, 60. doi: 10.1186/1477-7827-2-60
124. Tsunoda, Y., Yasui, T., Shioda, Y., Nakamura, K., Uchida, T., and Sugie, T. (1987). Full-term development of mouse blastomere nuclei transplanted into enucleated two-cell embryos. J Exp. Zool. 242(2), 147-151. doi:10.1002/JEZ. 1402420205
125. Tyler, M. J., Wassersug, R., and Smith, B. (2007). How frogs and humans interact: influences beyond habitat destruction, epidemics and global warming. Appl. Herpetol. 4, 1-18. doi:10.1163/157075407779766741
126. Ueda, Y., Yoshizaki, N., and Iwao, Y. (2002). Acrosome reaction in sperm of the frog: its detection and induction by oviductal pars recta secretions. Dev. Biol. 243, 55-64. doi:10.1006/DBIO.2001.0541
127. Uteshev, V., and Gakhova, E. (2005). Gene cryobanks for conservation of endangered amphibian species. Russ. J Herp. 12(Suppl.), 233-234.
128. Uteshev, V. K., Mel'nikova, E. V., Kaurova, V. A., Gakhova, E. N., and Kamaukhov, V. N. (2002). Fluorescence analysis of cryopreserved totipotent cells of amphibian embryos. Biophysics (Oxf) 47(3), 506-512.
129. Vellano, C., Bona, A., Mazzi, V., and Colucci, D. (1974). The effect of synthetic luteinizing hormone-releasing hormone on ovulation in the crested newt. Gen. Comp. Endocrinol. 24, 338-340. doi:10.1016/0016-6480 (74)90188-90189
130. Waggener, W. L., and Carroll, E. J., Jr (1998a). A method for hormonal induction of sperm release in anurans (eight species) and in vitro fertilisation in Lepidobatrachas species. Dev. Growth Differ. 40, 19-25. doi:10.1046/J.1440- 169X.1998.T01-5-00003.X
131. Waggener, W. L., and Carroll, E. J., Jr(1998b). Spermatozoon structure and motility in the anuran Lepidobatrachus. Dev. Growth Differ. 40, 27-34. doi:10.1046/J.1440-169X.1998.T01-5-00004.X
132. Watanabe, T., Itoh, T., Watanabe, A., and Onitake, K. (2003). Characteristics of sperm motility induced on the egg-jelly in the internal fertilization of the newt, Cynops pyrrhogaster. Zoolog. Sci. 20, 345-352. doi:10.2108/ ZSJ.20.345
133. Weldon, C., du Preez, L. H., Hyatt, A. D., Muller, R., and Speare, R. (2004). Origin of the amphibian chytrid fungus. Emerg. Infect. Dis. 10(12), 2100-2105.
134. Whitaker, B. R. (2001). Reproduction. In 'Amphibian Medicine and Captive Husbandry'. (Eds K. M. Wright and B. R. Whitaker.) pp. 285-299. (Krieger Publishing Co: Malabar, FL.)
135. Wildt, D. E. (1992). Genetic resource banks for conserving wildlife species: justifications, examples and becoming organised on a global basis. Anim. Reprod. Sci. 28, 247-257. doi:10.1016/0378-4320(92)90111-P
136. Wildt, D. E., Rail, W. F., Critser, J. K., Monfort, S. L., and Seal, U. S. (1997). Genome resource banks: living collections for biodiversity conservation. Bioscience 47(10), 1-19.
137. Williams, E. S., Yuill, T., Artois, M., Fischer, J., and Haigh, S. A. (2002). Emerging infectious diseases in wildlife. Rev. Sci. Tech. 21(1), 139-157.
138. Withgott, J. (2002). Amphibian declines. Ubiquitous herbicide emasculates frogs. Science 296,447-448. doi:10.1126/SCIENCE.296.5567.447A
139. Wolf, D. P., and Hedrick, J. L. (1971). A molecular approach to fertilization: II viability and artificial fertilization of Xenopus laevis gametes. Dev. Biol. 25, 348-359. doi:10.1016/0012-1606(71)90036-4
140. Yang, H., Carmichael, C., Varga, Z. M., and Xiersch, T. R. (2007). Development of a simplified and standardized protocol with potential for high-throughput for sperm cryopreservation in zebrafish Danio rerio. Theriogenology 68, 128-136. doi:10.1016/XTHERIOGENOLOGY. 2007.02.015
141. Young, B. E., Stuart, S. N., Chanson, J. S., Cox, N. A., and Boucher, T. M. (2004). 'Disappearing Jewels: the Status of New World Amphibians.' (Nature Serve: Arlington, VA.)