Effects of extenders, cryoprotectants and freezing methods on sperm quality of the threatened Brazilian freshwater fish pirapitinga-do-sul Brycon opalinus (Characiformes)
- 作者：A.T.M. Viveirosa ; anatmviveiros@hotmail.com ; L.H. Orfã ; oa ; A.F. Nascimentoa ; F.M. Corrê ; ab ; D. Caneppelec
- 关键词：Sperm motility ; Vitality ; Hatching rate ; Methyl glycol ; DMSO ; Cryopreservation
- 刊名：Theriogenology
- 出版年：2012
- 期刊代码：98_0093691x
- 类别：abs
- 出版时间：15 July, 2012
- 卷：78
- 期：2
- 页码：361-368
- 文件大小：453 K
摘要
The objective was to develop a suitable freezing method to cryopreserve Brycon opalinus (Characiformes) sperm. Extenders (NaCl and glucose at 325 and 365 mOsm/kg), cryoprotectants (dimethyl sulfoxide = dimethyl sulfoxide (DMSO) and methyl glycol = methyl glycol (MG)), equilibration times (15 and 30 min), thawing temperatures (30 and 60 掳C), and straw sizes (0.5 and 4.0 mL) were tested. Sperm were frozen in a liquid nitrogen vapor vessel at 鈭?70 掳C and subsequently stored in liquid nitrogen. Post-thaw sperm quality was always evaluated in terms of motility (expressed as percentage of motile sperm), duration of motility and vitality (eosin-nigrosin staining, expressed as percentage of intact sperm). The best freezing method was also tested for fertility and hatching (expressed as the percentage of fertilized eggs). Post-thaw sperm quality was highest when sperm were cryopreserved in Glucose 365 mOsm/kg and MG, after a 30-min equilibration and thawed at 60 掳C for 8 s, of regardless straw size: 74 卤 7%motile sperm, 47 卤 4 s of motility duration, 69 卤 3%intact sperm, 64 卤 4%fertilization and 63 卤 3%hatching. The freezing method developed in the present study was efficient and can be used to maximize larvae production for both aquaculture purposes and for conservational programs, since B. opalinus is a threatened species.