三个家猪品种和rob易位群染色体分带多态性的比较

对家猪不同品种及家系间的染色体组型、C－带、Ag－NORs多态性进行的研究表明：杜洛克猪、约克夏猪、长白猪体细胞染色体数2n＝38，核型2n＝10sm＋12m＋4st＋12t，而13／17易位纳合子猪（36，rob．13／17）的体细胞染色体数2n＝36，核型2n＝10sm＋12m＋6st＋8t；13／17易位杂合子猪（37，rob．13／17）的体细胞染色体数目为2n＝37，核型为2n＝10sm＋12m＋5st＋10t。5种家猪的C－带在13～18号染色体上存在大、中、小三种类型，且呈多态性分布。杜洛克猪、约克夏猪、长白猪、13／17易位纳合子猪、13／17易位杂合子猪的Ag－NORs均数分别为2．05、2．062．00、1．99、1．98，说明Ag－NORs在品种、个体及细胞间具有多态性.

Comparative Study on Polymorphism of the Banding Chromosome Among Three Breedsof Domestic Pigs and Rob Colony Translocation

The present experiment is carried out to make comparative stdy on polymorphism of chromosome Karyotypes, C-band and Ag-NORs of different breeds and strains in domestic Pigs. The results showed that the chromosome number of somatic cell in Duroc, Yorkshire and Landrace Pig Was 38and the karyotype was 2n =10sm 12m 4st 12t. But in heterozygous Rob 13 /17(37, rob. 13 /17) Pig, the chromosome number of somatic cell was 37 and the karyotype was 2n=10sm 12m 5st 10t, while in homozygous Rob 13 /17(36, rob. 13 /17) Pig, the somatic cell chromosome number was 36 and the karyotype was 2n = 10sm 12medst 8t. It was also showed that there were three C-band types in size on chromosome No. 13-18 showing polymorphism in three breeds and two strains of domestic Pigs. The average of Ag-NoRs in Duroc, yorkshire, Landrace, homozygous Rob. 13 /17 and heterozygous Rob.13/17 Pig was 2.05, 2.06, 2.00, 1.99 and 1.98, respectively. It is suggestod that Ag-NORs have polymorphism among strains, which can be used as a genetic index to analyse relationships among domestic animals with high reliability.