梅山猪及其杂种染色体研究——Ⅰ.染色体核型分析

Studies on Chromosomes of Meisan Swine and Its Hybrids I . Karyotype analysis

应用外周血淋巴细胞培养法对梅山猪、长·梅猪、汉·(长·梅)猪及杜·(长·梅)猪的染色体核型进行了研究。结果表明:四个类型猪的染色体数目均为19对。18对常染色体的形态,四个类型猪间没有明显的差异。X染色体差异最大,相对长度杜·(长,梅)猪最长,梅山猪次之,最短为汉·(长·梅)猪。四种类型猪第8号和第10号染色体的短臂着丝点处均有明显的次缢痕存在,10号染色体次缢痕更加明显。所观察的次缢痕显示率梅山猪最高(70％),长·梅猪次之(62.5％),汉·(长·梅)猪第三(57.5％),杜·(长·梅)猪最低(53.75％)。

The Karyotype of Meisan swine (M), the two-way hybrid of Landrace with Meisan (L M), the three-way hybrid of Hampshire with L M [H (L M)], and the three-way hybrid of Duroc with L M [D (L M)] were studied by means of leukocyte culture from peripheral blood in this research. All of the 4 swine types had 19 pairs of chromosomes (Table 1 and Figs. 1,2). No significant shape difference in the 18 pairs of autosomes was found a-mong the four types. However, prominent differences were shown in the X chromosome a-mong the four types; the X chromosome was longest in D (L M), followed by that of Meisan, and shortest in H (L M). There were secondary constrictions on the short arms of pair 8 and pair 10 chromosomes close to the centromere in these four types of swine, especially obvious in pair 10. Meisan swine showed the highest frequency of occurrence of secondary constriction(70%), followed by L M(62. 5%), H (L M) (57. 5%), and D (L M) (53.75%) (Table 2).