【摘要】 以凉山半细毛羊、山谷型藏绵羊为研究对象,以微量全血培养法制备染色体标本,采用Howell和Black(1980)的方法获得染色体Ag-NORs带,并对其进行比较。结果表明:在存在分歧的4、6号染色体间,依据染色体相对长度对染色体进行排序,将染色体NOR位点定位于4号染色体上;两品种羊NORs位点除分布在已报道的1p、2q、3q和4、25号染色体末端外,还分布在1、2号中着丝粒染色体的染色体臂上以及另外1或3条端着丝粒染色体臂上;并就Ag- NORs数目的多态性与生产性能相关性进行了探讨。更多还原

【Abstract】 Four Liangshan semifine-wool sheep and four Tibetan sheep were used to compare the karyotypes by Ag- banding techniques,which were employed on slides obtained from the peripheral blood cell culture.The result showed that: According to the relative length of chromosomes,the NOR was located on the terminal of No.4 not on the No.6,which was mistaken by some researchers;The nucleolus organizer regions(NORs)were located not only on the terminal of the 1p,2q,3q,4 and 25 chromosomes hut also on the arms of the No.1,No.2 and one or three telometric autosome chromo- somes;The relationship between Ag-NORs and productive performance was discussed.更多还原