香猪等五品种猪的C-带和银染带的分析和比较

THE ANALYSIS AND COMPARISON OF CHROMOSOME C-BAND AND Ag-NOR, IN VARIOUS PIG BREEDS

本文分析和比较了香猪、北京黑、长白、长北和社长北杂种的C-带和银染带。指出了家猪有可能存在Lin所没有揭示的异染质。得出了它们的NORs平均值分别为3.96、3.88、2.03、2.95和3.00。NORs联合率平均值为3.00％,但香猪高达7.31％。对香猪的结果分析表明,香猪具有以下细胞学特征:(1)染色体Y长;(2)染色体Y长臂C-带浅染;(3)D组染色体C-带具有极大的多态性;(4)染色体2～4之一的长臂有时出现C-带;(5)染色体NORs联合率高。

The C-band and Ag-NOR of chromosomes were analysed and compared in Xiang(X), Beijing Black(B), Landrace (L), L × B(LB), and Duroc× LB(DLB) pigs. It was possible that other different types of constitutive heterochromatin were existed in pig, besides what C.C. Lin were revealed. Results of silver-stain showed that the mean numbers of nucleolus organizer regions(NORs) were 3.96, 3.88, 2.03, 2.95 and 3.00 for X,B,L,LB and DLB respectively.Rate of association between NOR bearing chromosome was 3.00% on average, but it was up to 7.31% in Xiang.Analysing the results of Xiang showed that it possessed the following differences in cytology possibly. ( 1 )Longer chromosome Y; ( 2 ) Lightly stained in the long arm of chromosome Y; (3 )Distinct polymorphism in D group chromosomes; ( 4 )Sometimes, C-band was seen in the long arm of one of chromosome 2 to 4 ; (5 )highter NOR-associa-tion rate.