Testicular sperm can be cryopreserved and used at a later date using tradionally collected sperm by maceratation of testes (Browne et al. 1998) 
or by the more recent and nonlethal method of hormonally induced sperm collected in urine (Uteshev et al. 2013) and its cryopreservation (Shishova et al. 2011).
Physiological modifications to be considered for amphibian sperm cryopreservation are modifications related to extracellular osmolarity variation, 
effect of egg jelly components on sperm physiology, extracellular environment, role of calcium and bicarbonate in sperm physiology, 
and physiological changes after spermiation (Krapf et al. 2011). A recent study has reported on the effect of extracellular conditions (exposure to water and 
different temperatures) over time on the sperm motility and structural properties (morphology and DNA integrity) collected from hormonally stimulated Atelopus zeteki 
(Togna et al. 2018).





Krapf D, O’Brien ED, Arranz SE. 2011. Physiological modifications to be considered in amphibian
sperm cryopreservation. Pp. 100-106 In: Cryopreservation in Aquatic Species: A comprehensive overview 
of current practices, programmatic development and future directions for cryopreservation of gametes, 
embryos and larvae of aquatic species. 2nd Edition. Editors, Tiersch R, Green CC. World Aquaculture 
Society, Baton Rouge, Louisiana, USA. 1,003 p.

Salamandridae

Pleurodeles waltl

Uteshev et al. 2015

Not cryopreserved. Short-term refrigeratation storage of spermatozoa at +4 °C.


Only three reports of success in freezing and thawing viable caudate sperm have been made: two in Ambystomid species 
[Figel, 2013; Marcec et al, 2014], and two in Cryptobranchids [Unger et al, 2013; Peng et al, 2013].


Figel C. 2013. Cryopreservation of sperm from the axolotl Ambystom mexicanum: Implications for conservation. Herpetol Conserv Biol 8:748–855.

Marcec, R. Motility of Ambystoma tigrinum sperm before and after contact with egg jelly. Unpublished raw data.

Marcec R., Langhorne C, Vance C, Kouba A, and Willard S. 2014. Cryopreservation of Spermic Milt in the Model Species Ambystoma Tigrinum (Tiger Salamander) 
for Application in Endangered Salamanders. Cryobiology 69(3):515. doi:10.1016/j.cryobiol.2014.09.342.

Peng LY, Xiao YM., Liu Y, Kouba AJ, Vance CK, Zippel K, Shishova NV. 2013. Effect of cryopreservation and short-term storage of Chinese giant salamander sperm. Reproduction, Fertility and Development 25: 1,134.

Unger S, Mathis A, Wilkinson R. 2013. A comparison of sperm health in declining and stable populations of hellbenders (Cryptobranchus alleganiensis alleganiensis and 
C . a . bishopi). Am Midl Nat 170: 382–92.




Piril Erler, Alexandra Sweeney, James R. Monaghan. Regulation of Injury-Induced Ovarian Regeneration by Activation of Oogonial Stem Cells. STEM CELLS, 2016; DOI: 10.1002/stem.2504


Andrias davidianus

Cryptobranchus alleganiensis bishopi

Unger S, Mathis A, Wilkinson R. 2013. A comparison of sperm health in declining and stable populations of Hellbenders (Cryptobranchus alleganiensis
alleganiensis and C.a. bishopi). American Midland Naturalist 170: 382–392.




Additional

Silla, Aimee J. 2013. Artificial fertilisation in a terrestrial toadlet (Pseudophryne guentheri): effect of medium osmolality, sperm concentration and gamete storage
Reproduction, Fertility and Development 25(8): 1,134-1,141.

Successful cloning of coyotes through interspecies somatic cell nuclear transfer using domestic dog oocytes
Insung Hwang, Yeon Woo Jeong, Joung Joo Kim, Hyo Jeong Lee, Mina Kang, Kang Bae Park, Jung Hwan Park, Yeun Wook Kim, Woo Tae Kim, Taeyoung Shin, Sang Hwan Hyun, Eui-Bae Jeung and Woo Suk Hwang
Reproduction, Fertility and Development 25(8): 1142-1148