3种长江珍稀鱼类精子超低温冷冻保存的初步研究

Study on Sperm Cryopreservation of Three Rare Migratory Fishes in the Yangtze River

试验对西伯利亚鲟、美洲鲥鱼和暗纹东方鲀3种长江珍稀鱼类的精液进行超低温冷冻保存技术研究。以解冻后精子的活力为参数,探讨了稀释液、不同种类不同体积分数的保护剂、以及不同的精液稀释比例对实验鱼类精液进行超低温冷冻保存的保护效果。结果显示,3种长江珍稀鱼类以配方2和体积分数为10%甲醇组成抗冻保护剂,西伯利亚鲟精液按1:2稀释倍数,保存10天后检查精子活力,存活率可达(45±5.00)%。暗纹东方鲀精液按1:2稀释倍数,保存20天后检查精子活力,存活率可达(60.5±2.69)%。美洲鲥鱼精液按1:3稀释倍数,保存60天后检查精子活力,存活率可达(80.3±2.58)%。3种珍稀鱼类的精子保存以美洲鲥鱼效果最好。保存方法均采用三步法,在液氮面上方6 cm处平衡10 min,接着在液氮面上平衡5 min,最后投入液氮中冷冻保存。研究结果为保护长江珍稀鱼类的种质资源提供了理论基础。

The technique of sperm cryopreservation of three rare migratory fishes in the Yangtze River wasstudied,including Acipenser baerii,Alosa sapidissima and Takifugu obscurus.The success of spermcryopreservation was evaluated by post-thaw sperm motility.To explore methods for sperm cryopreservation,this study evaluated the effects of different extenders,cryoprotectants,their volume fractions,equilibrationtime and dilution ratios.The result showed that the best sperm cryopreservation of motility of Acipenser baerii was（45±5.00）% and Takifugu obscurus（60.5±2.69）% were obtained by following procedure：the ringer solutionand the semen were mixed at ratio of 2：1 in volume and added 10% methanol,while the best spermcryopreservation of motility of Alosa sapidissima（80.3±2.58）% was obtained by following procedure：the ringersolution and the semen were mixed at ratio of 3：1 in volume and added 10% methanol.Sperms werecryopreserved by three-step cooling progam.These results provided the methods to conserve genetic resourcesin three rare migratory fishes in the Yangtze River.