半滑舌鳎精子冷冻保存

半滑舌鳎精子冷冻保存对于人工繁殖育苗、杂交育种、雌核发育及其性别控制研究具有重要的意义，为此，本文对半滑舌鳎精子冷冻保存方法进行了研究。分别利用2．8mol／L的二甲基亚砜（DMSO）、甘油（Gly）和1，2-丙二醇（PG）冷冻保存该鱼精子。结果显示，DMSO冷冻保存精子的活力较高。利用MPRS＋2．8mol／L DMSO以1：0．5、1：1、1：1．5和1：2的比例稀释并冷冻精子，1：1比例在冻前能够抑制精子的运动，冻后活力可达82．50±3．54％，显著高于其他稀释比例（P〈0．05）。分别利用冷冻保存液A（MPRS＋2．8mol／L DMSO）和B（TS-2＋2．8mol／LDMSO）稀释平衡精子，精子在A中的冻前快速运动时间、寿命分别为37．75±6．45S和145．00±78．98S，与鲜精无显著差异（P〉0．05）。利用以上两种冷冻稀释液冷冻保存精子,精子在A液中的冻后活力和寿命分别可达53．50±6．69％和98．00±13．51s，冷冻效果优于B液（P〈0．05）。冷冻后精子的受精率和孵化率分别为55．00±5．00％和35．00±13．23％，受精率与鲜精无显著性差异（P〉0．05），因此认为MPRS＋2．8mol／L DMSO可用于半滑舌鳎精子的冷冻保存。

Cryopreservation of tongue sole Cynoglossus semilaevis sperm

Cryopreservation of tongue sole Cynoglossus semilaevis sperm offers benefits for artificial propagation,hybridization,gynogenesis and sex control.In order to develop a protocol to freeze tongue sole sperm,the effects of cryoprotectants,extenders and dilution ratio on motility,fertilization rate and hatching rate of frozen-thawed sperm were evaluated.Dimethylsulfoxide(DMSO)provided higher protection than glycerol and 1,2-propylene glycol during freezing and thawing.Motion time and life of sperm in A(MPRS +2.8 mol/L DMSO)and B(TS-2+2.8 mol/L DMSO)before freezing were 37.75±6.45 sec and 145.00±78.98 sec,which was not different from that of fresh sperm(P>0.05).The motility and life of frozen-thawed sperm in A were 53.50±6.69% and 98.00±13.51 sec,which was significantly higher than that of frozen-thawed sperm in B.When sperm were diluted with A at a ratio of 1:0.5,1:1,1:1.5 and 1:2,the highest motility(82.5±3.54%,1:1 dilution ratio)of frozen-thawed sperm was obtained and which was significantly higher than that of other dilution ratio treatment.According to the results above,tongue sole sperm were cryopreserved successfully with MPRS+2.8 mol/L DMSOat a dilution ratio of 1:1.As a result,the fertilization rate(55.0±5.0%)and hatching rate(35±13.23%)of frozen-thawed sperm were obtained,which was not significantly different from that of fresh sperm(P>0.05).