片吸虫核型的研究

STUDIES ON THE KARYOTYPES OF FASCIOLA SPP.

本文用空气干燥法制作片吸虫染色体,测量结果二倍体型染色体数为2n=20,n=10.三倍体型染色体数为3n=30,n=10。两者核型相似。二倍体型虫体与巨片吸虫相似,三倍体型虫体与肝片吸虫相似。一部分三倍体型标本中发现少数细胞具20个染色体,由10个单价染色体和10个双价染色体组成。经测量,这些染色体可分为10对,每对由1个单价染色体和1个双价染色体组成。

The karyotypes of diploid and triploid forms of the common liver fluke were analysed by air-drying method.The chromosome number of diploid form was 2n = 20,n=10, and the karyotype consists of the chromosomes with 2M, 4Sm, 3St, 1T. There were a number of similarities between the karyotypes of diploid form and triploid iorm except that the chromosome number of the triploid was 3n = 30 and n = 10. Judging from the shape of adult worms and their life cycle, the worm of the diploid form is similar to F, gigontica while the worm of the triploid form is similar to F. hepatita.In several specimens of the triploid worms there were some cells having 20 chromosomes that were composed of 10 monovalent chromosomes asd 10 divalent chromosomes. This kind of cell, in a group of 8 cells, was primary spermatocyte. According to the measurement, these chromosomes could be classified into 10 pairs and each pair was made up by one monovalent chromosome and one divalent chromosome. The karyotype of these chromosomes was similar to that of the triploid form. It is a rare phenomenon that one set of monovalent chromosomes and one set of divalent chromosomes co-exist during the same metaphasc (Figs. 1-4).