Studies On Cytogenetics And Blood Protein Polymorphism In Yanbian Yellow Cattle

Cytogenetics and blood protein polymorphism in Yanbian yellow cattle and Liyan hybrid cattle were studied in this paper. It was to provide basic data of cytogenetics for origin,evolution and gene location of Yanbian yellow cattle by karyotype and banding.Blood protein polymorphism is an effective measure to evaluate genetic diversity of Yanbian yellow cattle,genetic variation in strains and genetic relations between Yanbian yellow cattle and Liyan hybrid cattle.At the same time,this study will provide extensive theoretic bases to protect Yanbian yellow cattle genetic resourses.The karyotype and C-banding of Yanbian yellow cattle (10♀, 10 ♂) and Liyan hybrid cattle(14♀, 15♂) were studied with peripheral blood lymphocyte culture. The results showed as follows: The diploid chromosome number of Yanbian yellow cattle and Liyan hybrid cattle were 2n=60,the karyotype of bulls was 2n=60,XY,while cows were 2n=60,XX. 29 pairs of autosomes were telocentric. X chromosome was a large submetacentric chromosome. Y chromosome was a small metacentric chromosome.The relative length of chromosome was measured by AutoCAD software. The relative length of autosomes ranged from 1.545% to 4.921% in Yanbian yellow cattle and from 1.637% to 5.855% in Liyan hybrid cattle. The relative length of X chromosome in Yanbian yellow cattle was 5.001% and 5.640% in Liyan hybrid cattle. The relative length of Y chromosome in Yanbian yellow cattle was 1.928% and 2.045% in Liyan hybrid cattle. There was a significant difference between Yanbian yellow cattle and Liyan hybrid cattle in the relative length of chromosome, centric index and arm ratio (p<0.05) .It was similar in C-banding in Yanbian yellow cattle to that in Liyan hybrid cattle. All the centric positions of autosomes were dyed dark in both Yanbian yellow cattle and Liyan hybrid cattle and the arms were light. The whole X chromosome were dyed light. Y chromosome partly dyed, ranging from dark to light. Although the dyed positions of C-banding were similar, the shape and size of them were polymorphism.Three protein loci, including hemoglobin (Hb) , albumin (Alb) and transferrin (Tf) were analyzed with plate polyacrylamide gels electrophoresis (PAGE) in Yanbian yellow cattle and Liyan hybrid cattle. The results showed that three protein loci were polymorphism. There were 2 genotypes at Hb loci, namely AA and AB, which were controlled by 2 autosomal codominant alleles, A and B; 3 genotypes at Alb loci, namely AA , AB and BB, controlled by 2 autosomal codominant alleles;5 genotypes at Tf loci, namely AA, AD, AE, DE and EE, controlled by 3 autosomal codominant alleles, A, D and E.Genotype frequencies and gene frequencies between the two cattle populations were calculated by Statistical Product and Service Solutions. As a result, The genotype frequencies of AA at both Hb and Alb loci and DD at Tf loci were the highest. HbA, AlbA and TfD were the predominant alleles.According to the analysis of genetic variation, the gene homogeneity index, average heterozygosity, number of effective allele were 0.4048, 0.3425, 1.5209 in Yanbian yellow cattle and 0.2952, 0.3975,1.6597 in Liyan hybrid cattle.On the base of genetic distance and cluster analysis, the relationship between Yanbian yellow cattle and Liyan hybrid cattle is the nearest. Yanbian yellow cattle and Liyan hybrid cattle were classified into the population of Northern cattle. The range of the genetic distance between local cattle breeds was larger, but the distance between populations in the same area was smaller.