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作 者:杨家云[1]
出 处:《西南师范大学学报(自然科学版)》2005年第4期719-724,共6页Journal of Southwest China Normal University(Natural Science Edition)
摘 要:瓦氏黄颡鱼精巢呈栉状分支,每一分支内部结构为叶型,精巢小叶由许多壶腹状的精小囊组成.精巢发育分为精原细胞增殖期、精母细胞生长期、精母细胞成熟期、精子细胞变态期、精子成熟期和精子退化吸收期.精子的发生和形成经历了精原细胞、精母细胞、精子细胞到成熟精子的一系列过程.精巢后1/3的精巢尾区由上皮细胞构成,既无生精功能也无贮精作用.成熟精子在0.45%~0.55%盐溶液和pH 7.5的弱碱性的自然河水环境中保持的活性最好,并具有相当长的寿命.This paper gives a detailed summary of the research on the development of testis and biological characteritics of mature sperms of a freshwater catfish Pelteobagrus vachelli Richardson. According to the morphology and histology observation of the testis, it bears a seminal vesicle on either side, each vesicle is a comb-like structure in shape, composed of approximately 15-20 finger-like lobes. The testis lobes con- sist of many testicular envelops. The development of testis may be divided into six stages: Ⅰ . multiplication of spermatogonia; Ⅱ. growth of spermatocytes; Ⅲ. maturation of spermatocytes; Ⅳ. Initial appearance of spermatoblast; Ⅴ. complete maturation of spermatozoa;Ⅵ. degernation of spermatozoa. Mean- while, a large number of stage IV testes were found in the whole year. One-thind of the posterior portion of the testis composed of epithelial cells and this part of testis has no function of producing or storing sperms. The mature spermatozoa of Pelteobagrus Vachelli in 0.45 -0.55 % sodium chloride solution and in natural river with pH 7.5 weak alkaline reaction could keep its vitality the best and exist a rather long lifetime.
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