Collection and Cryopreservation of Hormonally Induced Sperm of Pool Frog ( Pelophylax lessonae )

Cryopreservation of urinal sperm is a new perspective technology for a long-term preservation of amphibian germplasm, including rare and endangered species. The article presents the results of experiments on the collection and cryopreservation of hormonally stimulated spermic urine of pool frog (Pelophylax lessonae). We used the luteinizing hormone releasing hormone analog (0.5 mu g hormone per 1 g of body weight) for a hormonal induction of spermiation. Volume, osmolality of spermic urine, concentration, motility and membrane integrity of hormonally induced sperm (HIS) were studied. HIS was cryopreserved with sucrose and dimethylformamide as the cryoprotectants. The fresh and cryopreserved sperm were used for artificial fertilization. The amount of eggs fertilized with fresh sperm was 64.5 +/- 5.8% whereas with cryopreserved sperm was 28.8 +/- 8.4%. We found no difference in the percentage of normally developing embryos after fertilization of oocytes with fresh and cryopreserved sperm.