甲基睾酮(MT)和加氢甲基睾酮(MDHT)浸泡法诱导尼罗罗非鱼仔鱼雄性化的对比研究

The Comparative Study on Masculinization of Larvae Nile Tilapia( Oreochromis niloticus) by Immersion in Androgen MT( 17α-methyltesosterone) or MDHT( 17α-methyldihydrotestosterone)

通过雄激素"浸泡法"诱导尼罗罗非鱼Oreochromis niloticus仔鱼雄性化的研究,探索一种雄激素浸泡诱导尼罗罗非鱼仔鱼雄性化的技术方法。选用了可芳化的MT(17α-methyltesosterone)和不可芳化的MDHT(17α-methyldihydrotestosterone)两种雄激素进行对比试验。进行了处理时期(1,7,13 DPH,Days Post Hactching),激素剂量(200,600,1 800,5 400μg·L-1),持续时间(2,4,8 h)3个因素的简单比较法正交试验。结果如下:当诱导7 DPH仔鱼、持续时间为4 h时,MT剂量为600μg·L-1时雄性率最高,为98.81%,而剂量1 800,5 400μg·L-1时雄性率明显下降(P<0.05);MDHT剂量为600,1 800μg·L-1时,雄性率最高,分别为98.34%和98.39%,剂量为200,5 400μg·L-1时雄性率没有明显下降(P>0.05)。当用MT诱导7 DPH仔鱼,剂量为600μg·L-1时,持续时间为4 h的雄性率最高、而8 h的雄性率明显下降(P<0.05);当用MDHT时,3种持续时间(2,4,8 h)的雄性率无明显差异(P>0.05)。总体来看,应用MT和MDHT的雄性率都能达到生产应用需求,但MDHT效果更稳定、表现出更好的应用潜力。

In this paper, we concentrated on masculinization of larvae Nile Tilapia （Oreochromis nilotic- us） by immersion the larvae in androgens MT （17α-methyhestosterone） or MDHT （17α-methyl- dihydrotestosterone）. The three factors were considered： treatment period （1, 7, 13 DPH, Days Post Hatching）, hormone dose （200, 600, 1 800, 5 400 μg·L^-1）, and treatment duration （2, 4, 8 h）. All these three factors were taken into account by simple comparison orthogonal experimental design. The main results are as follows ： the 7 DPH larvae induced by MT at a dose of 600 μg·L^-1 with 4 h treatm duration is the best result of masculinization, male rate is 98.81% , while at a dose of 1 800 μg·L^-1 5400 μg·L^-1, male rate greatly decreased （P〈0.05）; 600 μg·L^-1 or 1 800 μg·L^-1 dose of MDHT present the best results of masculinization, male rate is 98.34% and 98.39% respectively, at a dose of 200 μg·L^-1 or 5 400 μg·L^-1 male rate are not significantly decreased （ P 〉 0. 05 ） . When 7 DPH larvae were induced by MT at a dose of 600 μg·L^-1, 4 h is the best treatment duration, 8 h pres- ents greatly decreased result （P 〈 0.05） ; When MDHT was used, three treatment durations （2, 4, 8 h） got consistent results （P 〉 0. 05 ）. The conclusion is that MT and MDHT can both achieve masculin- ization goals for application of production, but MDHT is more stable and show a better application value.