红鳍东方鲀性腺发育的组织学研究

Histological Observation of Gonadal Development of Tiger Puffer Takifugu rubripes

为查明红鳍东方鲀性腺的发育规律,采用组织学方法对2019年6月至2021年4月采集的不同发育时期红鳍东方鲀样本进行分析。试验结果表明,红鳍东方鲀雌鱼属一次性产卵类型,精巢和卵巢均为封闭型。根据精子和卵子发生过程可知,雄鱼精巢属于全囊成熟型,雌鱼卵巢属于部分同步型。根据卵母细胞的形态结构、卵黄物质的积累和滤泡细胞变化特征,将卵子发生划分为6个时相;根据生精细胞形态结构的变化,将精子发生分为5个阶段。根据性腺的外部形态特征、大小、颜色以及组织学特征等,将红鳍东方鲀卵巢及精巢发育过程划分为6个时期。此外,雄鱼、雌鱼性腺指数在进入发育期后快速升高,Ⅴ期时达到峰值,显著高于发育前水平(P<0.05),产卵排精后,明显降低(P<0.05),与性腺发育的变化趋势保持一致。在雄鱼精巢发育过程中肝脏指数在Ⅱ期和Ⅲ期无显著差异(P>0.05),随性腺发育在Ⅳ期开始显著下降(P<0.05)。雌鱼变化不同于雄鱼,雌鱼肝脏指数在各个时期之间无显著差异(P>0.05)。而雄鱼、雌鱼的肥满度在整个繁殖周期变化并不突出(P>0.05)。上述研究成果对红鳍东方鲀繁殖生物学的认知具有重要意义。

In order to understand gonad development of tiger puffer Takifugu rubripes, 212 samples of tiger puffer in different developmental stages were collected from June 2019 to April 2021. It was found that the female of tiger puffer was a one-time spawning type, with closed-type testis and ovaries. According to the process of spermatogenesis and oogenesis, the testis of males was cystic type, and ovaries of females were partly synchronized. According to the morphological structure of oocytes, the accumulation of yolk matter and the changes in follicular cells, oogenesis was divided into 6 phases, and spermatogenesis divided into 5 phases according to the changes in spermatogenic morphology and structure. According to the external morphological characteristics, size, color, and histological characteristics of the gonads, the development process of the ovaries and testes were divided into six stages. In addition, the male and female gonadosomatic index(GSI) was shown to be increased rapidly after entered the developmental stage, with peak at stage Ⅴ, significantly higher than the pre-developmental level(P<0.05), and significantly decreased after spawning and ovulation(P<0.05), and gonadal development maintained a consistent trend of change. There was no significant difference in the hepatosomatic index(HSI) between stage Ⅱand stage Ⅲ during the development of the testis in the male(P>0.05), and then the HSI was gradually decreased. Female changes were different from male, without significant difference in HSI of female between samples at various periods(P>0.05). However, the condition factor(CF) of the male and female did not change significantly throughout the reproductive cycle(P>0.05). The findings are of great significance to the cognition of the reproduction biology of tiger puffer.