Studies On Taihe Silkies' Karyotype, Banding Patterns & The Correlation With Performances

Incubating the Taihe Silkies ' peripheral blood ,made the chromosome slides,showed up the germplasm characteristics by analyzing the karyotype,G-band,C-band,Ag-NORs and the correlations between karyotype,G-band,Ag-NORs and the performances in Taihe Silkies.1. Succeeding in sliding shows the refined peripheral blood lymphocyte culture-drying naturally is an effective approach for chicken cytogenetic study.2.The diploid chromosomal number of Taihe Silkies is 2n=78,and the basic number of chromosome arms is NF=90.These chromosomes consist of 10 pairs of macrochromosomes and 29 pairs of microchromosomes,and the sex chromosome type is ZZ/ZW. According to the measured relative lengths,arm ratio and centromeric index , the first 10 pairs of chromosomes are described as follow:NO. 1 , 9 and Z,W chromosomes are metacentrics,NO. 2,4,7 are submetacentrics,and pair 3,6,8,10 are telocentrics.3. The characteristics of G-band in the Taihe silkies' prometaphase configuration are described in detail.Compared with LueYang chicken, there are some differences in NO. 2and 9 chromosomes:There are 2 more dark bands in the short arms and 1 more dark band in the long arms in No. 2,and Imore dark band in the short arm ,2 more dark bands in the long arm in NO.9 in Taihe silkies' chromosomes than in LueYang chicken.4.Ag-NORs are located in the short arms' telomere of NO. 1,2 euchromosomes and Z sex chromosome in Taihe silkies and the mean value per cell of male and female is 2.94 and 2.96 respectively.lt 's evident that there are differences and polymorphism in the number of Ag-NORs between different individuals and between different cells of the same individual.The result could be used in exploring the origin and evolution of our country's native chicken breeds and analyzing the relationship among the breeds.5.The model maps of routine karyotype and G-band of Taihe silkies are made.In the G-band model map,the first ten pair chromosomes are divided into 29 zones and 190 bands .This shows the characteristics of Taihe silkies karyotype and G-band more distinctly,which may be the convincing reference basis for the sudying of chromosome aberration and gene maping.6.Being treated by C-banding technique,a totally dark-stained and easily indentified W-chromosome always shows up in the female metaphase configuration,but doesn' t show up in the male.lt proves furtherly that C-banding technique is an effitive approach in chicken sex indentification.7.Analyzed the correlation between Taihe silkies' karyotype,G-band,Ag-NORs and the performances firstly in our country.The results are as follow:The karyotype parametrics of the first ten chromosome have a significant or a highly significant correlationship with part of productive traits.NO.4 chromsome has a close correlation with many productive traits. ,which may be a new cytogenetic marker trait for the preserving, exploiting and using of our country' s native chicken breeds ;There are two distinctive tendencies:The higher the G-banding frequency is,the better the performances are,and the more the number of Ag-NORs is,the better the performances are in Taihe silkies.