【摘要】 通过光学显微镜对染色体数为150±的三倍体和染色体数为100的二倍体银鲫(Carassius auratus gibelio Bloch)的精巢组织学结构进行了比较观察。三倍体和二倍体银鲫的精巢组织学结构基本相同,属于小叶型,都是由外膜和实质构成,各精小叶呈辐射状分布,一个小叶由数个精小囊组成。其精原细胞存在于精小叶内壁上,精母细胞和未成熟的精子细胞位于精小囊中,精子成熟后从精小囊进入小叶腔。三倍体银鲫成熟精子的体积为(11.8±2.8)μm3,二倍体平均为(6.8±1.8)μm3,二者的比例接近3:2。结果表明三倍体银鲫的精巢能够发育成熟,其精子发生过程正常,经过减数分裂,能产生正常的精子;因此三倍体的黑龙江银鲫是具有双倍性特征的多倍体群体。更多还原

【Abstract】 The curcian carp(Carassius auratus gibelio Bloch) is distributed mainly over Europe,northeast and northwest China.In northeast China,especially in Heilongjiang water,the crucian carp has two subspecies.The one was considered to be troploid that has 150± chromosomes in its somatic cells,and reproduces by gynogenesis.There are only some 5%-25% males in this population.The other was regarded as diploid whose somatic cells has 100± chromosomes.Spermary histological structures of triploid and diploid in crucian carp(Carassius auratus gibelio Bloch) were investigated by means of light microscope.The results indicated no abnormalities were found in spermatogenesis of the triploid,and its spermary which is similar to the diploid is lobular type which constituted by out membrane and parenchyma.The seminiferous lobulas are composed of several cysts and distribute in radiation.The spermatocyte and immature spermatid located in the spermatogenic cysts,after spermatozoa have matured,the spermatozoa were released into lumen of seminiferous lobula out of the spermatogenic cysts.There were several leydig cells among seminiferous lobulas.However,mature spermatozoa in lobule lumen of the triploid were obviously less than those in the diploid.The crucian carp may have reproduced gynogeneticaly before diploidization but has now become diploid in behaviour.The change of reproductive form might be a long transition period.The triploid is fertile and can form mature spermatozoa after meiosis,which was regarded as triploid would be hexaploid or is undergoing the course of diploidization.更多还原