| Associate Prof Liu Bang Associate Prof Yu Mei (College of Animal Science and Medicine Veterinary , HZAU ,China)The research has been divided into two parties. In the first part the karyotypes of metaphase chromosomes in mitotic cells of seven species of fowls (Jianghan fowl, Guifei fowl, Pheasant, Jinshui silky fowl, Heifeng fowl,Quail and Partridge) were made by the lymphocyte culture. The cluster analysis of karyotype resemblance-near coefficient was made by measuring the relative length and the centromeric index of the former 10 pairs of chromosomes . In the second part the karyotypes of metaphase chromosomes in mitotic cells of fowls (AA broiler, Jingbai layer, Jianghan fowl) from three breeds were also made by lymphocyte culture , then the relative lengths of the W chromosomes were measured . The major economical traits of the fowls were determined by physiological and biochemical methods , and the results were gained by statistic analysis.1 The seven species of fowls had been clustered into three clusters. Cluster I included Jianghan fowls and Guifei fowls .Pheasants , jinshui silky fowls and Heifeng fowls were included into cluster II , whereas quails and partridges were included into the cluster III . The cluster result was similar to the classiffication of traditional morphological taxanomy. The resemblance-near coefficient (λ.) in cluster I was 0.9443 . In cluster lithe Jinshui silky fowls and Heifeng fowls were clustered firstly ( A =0. 9759) , but pheasants were clustered into cluster II only when the resemblance-near coefficient was 0. 6992 . The result suggested that pheasants was relatively primitive evolutionarily .The quails and the partridges had a lower resemblance-near coefficient ( λ =0.5371) .which indicated they were not very similar to each other .2 Of the three clusters Jinsui silky fowls and Heifeng fowls of the group II had a bigger genetic relationship or homology than the cluster I , and the cluster III was least .which showed that quails and partridges of cluster III had a earliest differentiation while the cluster II had a latest differentiation,and the cluster I was between the former two . So quails and partridges were probably the most primitive cluster. Obviously the natural classification attribute and the evolutionary process of seven species of fowls were completely indicated by the classification sequence of karyotype resemblance-near coefficients.3 The differences among the relative length of W chromosomes of AA broiler , Jingbai layer , Jianghan fowls were sharply significant (p<0.01). Yet the relative length of W chromosome from the same breed fowls had not obvious differences (p>0.05).4 The relative length of W chromosome from every breed and the alive weight of fowl as well as the thigh weight had obvious differences (p<0.01). The relative length of W chromosome from every breed was positively correlative with the dressing percentage, semi-eviscerated percentage and eviscerated percentage, but the correlation was not obvious (p>0.05). Furthermore, the major economical traits of fowls had not consistent correlation.5 Excluding differences from breeds the relative length of W chromosome of fowl was extremely correlative with the alive weight and the thigh weight respectively, and the correlative coefficients (r) were respectively 0.5755 (p<0.01) and 0.4906 (p<0.01). But no significant correlation existed between the relative length of W chromosome and the other three economical traits (p>0.05). |
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