【作者】 姚汶励； 姜鹏； 白俊杰；

【Author】 YAO Wenli;JIANG Peng;BAI Junjie;Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences;Shanghai Collaborative Innovation for Aquatic Animal Genetics and Breeding;Shanghai Ocean University;

【机构】 中国水产科学研究院珠江水产研究所农业部热带亚热带水产资源利用与养殖重点实验室； 水产科学国家级实验教学示范中心上海海洋大学；

【摘要】 为了充分利用草鱼雌性个体在大规格养殖阶段所表现出的生长优势,探索培育全雌草鱼新品种,本研究初步开展了草鱼性别控制技术研究。选择具有代表性的雄性激素17α-甲基睾酮（17α-MT）,采用激素拌料投喂诱导方式,设置0mg·kg^-1、50mg·kg^-1、100mg·kg^-1、200mg·kg^-14个浓度梯度,投喂周期150d,通过观测不同处理水平草鱼性腺结构和血清性类固醇激素含量变化的特点,探究草鱼性逆转发生的规律。组织学切片结果显示:50mg·kg^-1 MT可以抑制卵母细胞的生成及成熟,致使发育迟缓;100mg·kg^-1 MT处理雌鱼使其性腺边缘开始出现大量精原细胞,有向精巢发育的趋势,绝大部分处于间性;但200mg·kg^-1 MT则会出现精原细胞较少,卵细胞过早成熟和空泡化共存的极化现象。此外,不同剂量MT处理雄鱼,其精原细胞不同程度萎缩,尤其200mg·kg^-1 MT最为明显。血清结果显示:在雌性草鱼中,投喂不同剂量的17α-MT,雌二醇（estradiol-17β,E2）浓度均显著升高,于30d时达到最高,之后趋于平稳下降但都极显著高于对照组,而睾酮（testosterone,T）和11-酮基睾酮（11-ketotestosterone,11-KT）浓度变化不显著。而正常对照雄鱼中,随着精巢的发育,其E2逐渐升高,与100mg·kg^-1变化为同一水平。研究表明:不同剂量的MT均可使雌鱼血清雌二醇升高、性腺中卵细胞退化,精原细胞增殖,其中100mg·kg^-1为较适宜的浓度使其性逆转。更多还原

【Abstract】 In order to make full use of the growth advantages of female individual in large scale breeding stage, the new varieties of whole-female grass carp will be explored, and the study of sex control technology of grass carp was preliminaryly carried out. The 17α-methyltestosterone（17α-MT） was selected as the representative male hormone, and set 4 concentration gradients evenly mixed with feed, such as 0 mg·kg^-1,50 mg·kg^-1,100 mg·kg^-1,200 mg·kg^-1,which were respectively fed for 150 days. The morphological changes of grass carp were investigated by observing the changes of gonadal structure and serum steroid hormone content at different treatment levels to explore the sexl reversal. Histological biopsy results showed that:50 mg·kg^-1 MT can inhibit the formation and maturation of oocytes, resulting in developmental delay;100 mg·kg^-1 MT treatmented made females gonadal edge began to appear a large number of spermatogonia, most of them were intersexuality;however,200 mg·kg^-1 MT will appear less spermatogonia, egg cell premature maturation and vacuolar coexistence of the polarization phenomenon. In addition, the spermatogenic cells at different degrees of atrophy by different doses of MT treatment of males, especially, 200 mg·kg^-1 MT was the most obvious. The results of serum revealed that during female with treatments, estradiol-17β（E2）were significantly increased and reached the highest at 30 days, and then decreased steadily but overall was significantly higher than that in the control group. While the changes of testosterone（T） and 11-ketotestosterone（11-KT） were not significant. With the development of the normal male testis, the E2 gradually increased, with 100 mg·kg^-1 changes in the same level. The results showed that different doses of MT could increase the serum estradiol, the degeneration of egg cells in the gonad and the proliferation of spermatogonia, and 100 mg·kg^-1 was more suitable concentration to bring about sex reversal.更多还原