拉萨裂腹鱼人工繁殖初探

Preliminary study on artificial propagation of Schizothorax waltoni

为探索拉萨裂腹鱼(Schizothorax waltoni)人工规模化繁殖技术,于2019年4月获得4批拉萨裂腹鱼亲本,鱼卵能自然流出的直接进行人工繁殖,不能自然流出的采用DOM+LHRH-A2进行人工催产,统计催产率、产卵量、受精率和孵化率。结果显示:自然产卵亲本体重(1643±395)g,体长(51.64±3.08)cm,60组,共计产卵77.58万粒,受精率(85.10±11.13)%,孵化率(85.75±20.89)%。人工催产雌鱼体重(1574±375)g,体长(50.79±3.63)cm,催产率90.36%。雌鱼总产卵量93.29万粒,受精率(79.07±16.14)%,孵化率(87.86±24.80)%,雌鱼催产效应时间72~96 h。随着人工催产时间增加,雄鱼精液量及4℃下有效保存时间均呈先升高后降低趋势,且在第2天精液量最多,4℃下有效保存时间最长,催产第3天后,精液量和有效保存时间均显著降低。结果表明,采用DOM和LHRH-A2组合对拉萨裂腹鱼进行人工催产,可获得较高的催产率、受精率和孵化率;自然成熟鱼卵受精率较人工催产受精率高,产卵量较人工催产低;拉萨裂腹鱼雄鱼最佳催产效应时间为2 d。

Four batches of parents of Schizothorax waltoni were obtained in April 2019 to explore the artificial large-scale propagation technology of it.The eggs flow out naturally could be used for artificial egg preparation,insemination and hatching.The ones that could not flow out naturally was used for artificial abortion.The fertility rate,spawning amount,fertilisation rate and hatching rate were counted.The study was conducted on the technology of large scale artificial propagation of S.waltoni from March to April in 2019.A total of 775800 eggs were collected from 60 groups of natural spawning in 4 batches of parents The results showed that the weight of parents was(1643±395)g,the length was(51.64±3.08)cm,the fertilization rate was 85.10%±11.13%,and the hatching rate was(85.75±20.89)%.A total of 83 fishes of the two groups of artificially spawning females were induced by 10 mg DOM+10μg LHRH-A2,of which 75 fisheswere spawned by one injection,and the rate of induced spawning was 90.36%.The body weight of female was(1574±375)g,the body length was(50.79±3.63)cm,the total number of eggs laid was 932900,the fertilization rate was(79.07±16.14)%,and the hatching rate was 87.86%±24.80%.The effect time of female was 72~96 h.With the increase of artificial induction time,the semen quantity of male increased first and then decreased.The semen quantity was the best in the second day,and the sufficient preservation time was the longest.After the third day,the sufficient preservation time of semen decreased significantly.Therefore,the combination of DOM and LHRH-A2 could be used to artificially speed up the spawning of S.waltoni,which could achieve a high rate of fertility,fertilization and hatchability.The fertilisation rate of natural mature fish eggs was higher than that of artificial spawning,and the spawning volume was lower than that of artificial spawning.The best time for the spawning effect of male S.waltoni should be 2 days.