实验以白斑狗鱼(Esox lucius)同一家系人工授精孵化的仔鱼为研究对象,用经浓度为20 mg/L 17α-甲基睾丸酮(17α-MT) 浸泡的饵料分别在仔鱼生长的不同时期(出膜10、20、30、40 d) 投喂,持续投喂30 d,待仔鱼培育至7月龄将其解剖取出性腺,进行组织学观察.结果显示:投喂17α-MT对其有显著致死效应;在10 d喂药组出现较高的雄性率(40.8%),其它3个试验组雄性率相对较低,而对照组雄性率仅为26.3 %,由此推断白斑狗鱼性腺分化转雄的时间节点在出膜10~20 d.在试验过程中发现白斑狗鱼性腺分化在稚鱼阶段存在精巢组织与卵巢组织共存现象,根据其性腺的组织学特征推断白斑狗鱼性腺分化方式可能是未分化型雌雄异体型.%This study took artificial fertilization hatching larvae of Esox lucius in the same family as the research object.The larvae were continuously fed for 30 d at different growth periods(after hatching 10 d, 20 d, 30 d, 40 d) with baits, which were soaking in 17 alpha-methyl testosterone(17α-MT) with concentration of 20 mg/L.When the larvae were cul-tured to 7 months old, the gonads were dissected and removed to do the histological observation.The results showed that feeding 17α-MT had significant lethal effect.The male rate of 10 d hatching larvae group was higher(40.8%) than other gourps.The male rate of the orther three experimental groups was relatively low, while the male rate of the control group was only 26.3%.Infer from these results, the time of gonadal differentiation turn to male for E.lucius was after hatching 10~20 d.The experiment found that pike gonadal differentiation in the juvenile stage testis tissue and ovarian tissue coexis-tence phenomenon exists.According to the characteristics of the gonad histological features that pike gonadal differentiation might be undifferentiated type and gonochorism.
展开▼
