Chromosome Karyotype Analysis of Carassius auratus var. Dongtingking and Cultivar Identification

Metaphases of Carassius auratus var.Dongtingking were prepared directly from kidney cells in vivo.Its chromosome number in all counted complete metaphases is 100.Analysis of chromosome can be divided into four sections according to the position of the centromere,which were metacentric chromosome,submetacentric chromosome,subtelocentric chromosome,and telocentric chromosome.There were 30 metacentric chromosomes,20 submetacentric chromosomes,26 subteocentric chromosomes and 24 telocentric chromosomes.Each homologous chromosomes group contained three complete matched homologous chromosomes.The DNA relative content of muscle cells C.auratus var.Dong.and C.auratus var.Red were measured by a flow cytometer.The DNA relative content of muscle cells C.auratus var.Dong.is(55.75±1.59)(17 specimens).In the classical diploid control group of C.auratus var.Red,the DNA relative content of in vivo cells is(55.68±1.64)(15 specimens).The ratio of DNA relative content of C.auratus var.Dong.and that of diploid C.auratus var.Red is 1∶1.This was consistent with analytic result of chromosome.These results suggested that C.auratus var.Dong.was a double Carassius auratus with a chromosome number of 2n=100.The karyo formula was 2n=30m+20sm+26st+24t,NF=150.