鲇精子超微结构及pH、温度对其精子活力的影响

为了解鲇Silurus asotus精子的结构特征,应用扫描电镜和透射电镜技术,对体质量为320~550 g的鲇成熟精子结构进行了观察。结果表明:鲇精子由头和尾两部分组成,无明显颈部;精子头部近球形,直径为1.85~2.51μm,头部无顶体,头部内有高度密集的细胞核染色质,头部后方凹陷形成植入窝,植入窝内有近端中心粒和远端中心粒,细胞核后方与质膜的间隙较大(称袖套),其内富含细胞质、线粒体和囊泡等细胞器;尾部细长,无主段和尾段之分,长为44.3~50.7μm,横切面呈圆形,直径为0.269~0.308μm,透过横断面可见,鲇精子尾部由轴丝和附属纤维构成,外有一层质膜包裹,轴丝与远端中心粒形成"9+2"微管结构。研究表明,精子活力的适宜pH为7.0~8.5,适宜温度为25~29℃,当pH为8.0、温度为28℃时,精子活力最强。

Ultrastructure of spermatozoon and effects of pH and temperature on spermatozoon motility in oriental sheatfish Silurus asotus

The ultrastructure of spermatozoa of oriental sheatfish Silurus asotus with body weight of 320-550 g was observed by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and effects of pH and temperature on spermatozoon motility in oriental sheaffish.The spermatozoa were shown to be primarily consists of head and flagellum,with no obvious neck.The spermatozoon has a round head with a diameter from 1.85 μm to 2.51 μm,containing highly condensed chromatin,without acrosome or acrosomal vesicles.There were fossa containing proximal centrioles and distal centrioles in the end of the head.There were rich cytoplasm,mitochondria,and vesica in sleeve distributed between unclei and plasma membrane.The slender flagella consisting of axoneme and accessory fibers have length of 44.3 μm to 50.7 μm,with a round cross section and a diameter of 0.269 μm to 0.308 μm.A typical structure of “9+2” model was observed in the axoneme and distal centrioles.It was found that 7.0-8.5 pH was the suitable for spermatozoon,with the maximal motility at 8.0 pH and that 25-29 ℃ was the suitable temperature for spermatozoon,the maximal motility at 28 ℃.