中文摘要：

借助扫描电镜和透射电镜对尼罗罗非鱼（Oreochromis niloticus）、奥利亚罗非鱼（O.aureus）、奥尼罗非鱼（O.niloticus×O.aureus）和吉富罗非鱼（GIFT Strain in Nile Tilapia,O.niloticus）成熟精子的超微结构进行了比较研究。结果显示,4种罗非鱼精子均为有鞭毛精子,无顶体,尾部轴丝9±2型。尼罗罗非鱼精子植入窝陷入核深度最浅,线粒体个数和平均直径分别为5-9个、（0.36±0.10）μm,鞭毛侧鳍平均翼长为（0.29±0.11）μm;奥利亚罗非鱼精子核内染色质着色程度最深,植入窝陷入核深度约1/3,线粒体个数和平均直径分别为3-10个、（0.40±0.17）μm,鞭毛侧鳍平均翼长为（0.32±0.12）μm;奥尼罗非鱼精子核内染色质着色程度较浅,植入窝陷入核深度约1/3,线粒体个数和平均直径分别为5-7个、（0.32±0.09）μm,鞭毛侧鳍平均翼长（0.26±0.09）μm;吉富罗非鱼精子核内染色质着色最浅,植入窝陷入核最深,约占2/3,线粒体个数和平均直径分别为5-10个、（0.37±0.08）μm,中段存在大量中空囊泡,鞭毛侧鳍平均翼长为（0.15±0.03）μm,与其它三种罗非鱼精子鞭毛平均侧鳍翼长比较具显著性差异（P〈0.05）。

英文摘要：

Spermatozoa ultrastructures of Oreochromis niloticus , O. aureus , O. niloticus × O. aureus and GIFT Strain in 0. niloticus were observed and compared by means of scanning electron microscope （SEM） and transmission electron microscope （TEM）. The results showed that ： all of the tilapias spermatozoa had flagellum with ＂9 ± 2＂ pattern but no acrosome. The differences among them included：for O. niloticus the implantation fossa in sperm nuclear was the shortest in the four kinds of tilapias, the mitochondria number and average diameter were 5 - 9 and （0. 36 ± 0. 10） μm respectively and the average length of lateral fin of sperm flagellum was （ 0. 29± 0. 11 ） μm ; for O. aureus the chromatin in sperm nuclear was the darkest,the implantation fossa reached into 1/3 depth in the sperm nuclear, the mitochondria number and average diameter were 3 - 10 and （0. 40 ± 0. 17 ） μm respectively and the average length of lateral fin of sperm flagellum was （0. 32 ± 0. 12 ） μm ;for O. niloticus × O. aureus the chromatin in sperm nuclear was light, the implantation fossa reached into one third depth in the sperm nuclear, the mitochondria number and average diameter were 5 - 7 and （0. 32 ± 0. 09）μm respectively and the average length of lateral fin of sperm flagellum was （ 0. 26 ± 0. 09） μm ; for GIFT Strain in O. nilotieus the chromatin in sperm nuclear was the lightest and the implantation fossa deepest reached into sperm nuclear （ about 2/3 thirds） in the four kinds of tilapias, the mitochondria number and average diameter were 5 - 10 and （0. 37 ± 0. 08） μm respectively, so many empty vesicles were in the middle piece and the average length of lateral fin of sperm flagellum was （0. 15 ±0. 03 ） μm which had significant difference compared with the other three kinds of tilapias.