Study On Enzymes Activity In The Blood And Genetic Diversity Of Sheep Breeds

Abstact:Blood samples was taken from four populations of Qinghai Tibetan, Qinghai Small tail han sheep , Gansu Alpine Merino ,Mongolian and Small tail han sheep to analyze the activity of enzymes and the isozymes polymorphisms by means of vertical polyacrylamide gel electrophoresis (PAGE). The results showed that :Activities of Amylase and peroxidase were different not only in the sheep breeds that live in the same environmental condition , but also in small tail han sheep that lie on the different ecotope , which indicated enzyme activities were affected by species character and change for the environmental transition, physiological function for the metabolic activity ,nutritional level of fodder and so on. Lactate dehydrogenase activity was controlled by genetic message.The polymorphisms was found at three isozymes loci of serum amylase and esterase , Amy2 and Es was controlled by two alleles in the four populations , respectively . Tibetan phenotypes distribution frequenecy of Es(+)was the largest(0.9333),that of Gansu Alpine Merino was the smallest(0.5666). Phenotypes distribution frequenecy of Amy2 was the largest(0.5333) in Gansu Small tail han sheep,that was the smallest(0.2143) in Tibetan. However , The polymorphisms was not found at Amy 1,Amy 3 and Cp. Effective number of alleles and percentage of polymorphic loci were analyesed in four sheep populations,2 Small tail han sheep populations were the highest in the effective number of alleles, Tibetan was the lowest. Gansu Alpine Merino and Mongolian were higher than Tibetan. Four sheep populations were the same in percentage of polymorphic loci(40.00ï¼…).The degree of genetic variability estimated by Nei's expected average heterozygosity and relative Shannon entropy for the five isozymes loci. Small tail han sheep has relatively higher heterzygosity and relative Shannon entropy than other sheep breeds in different ecology environment.It was show that 2 Small tail han sheep has higher genetic variability than others,Tibetan was the lowest .The genetic variation of five populations was examined by applying relative Shannon entropy , The result indicated that the main reason of the four population's gene variation is the continuous exist of heterozygosity.