【作者】 杨永新；

【导师】 崔泰保；

【作者基本信息】 甘肃农业大学 ， 动物遗传育种与繁殖， 2004， 硕士

【摘要】 本研究采用垂直板聚丙烯酰胺凝胶电泳技术，以青藏高原区民和县园艺场小尾寒羊和藏羊；荒漠生态环境区酒泉双塔农场蒙古羊、甘肃高山细毛羊和小尾寒羊为研究对象，检测了不同绵羊品种（群体）血清淀粉酶（Amy）、乳酸脱氢酶（LDH）和过氧化物酶（POD）的活性以及血清酯酶（Es）、Amy、LDH、POD和铜蓝蛋白（Cp）五个同工酶位点的多态性。酶活性分析结果表明，Amy和POD活性既受遗传基因的控制，又受生态环境及饲养管理水平等外界因素的影响；LDH主要受遗传因素的影响，对外界环境因素具有相对独立性。同工酶位点分析结果表明，所检测绵羊品种（群体）中，Es和Amy2两个基因座存在多态性，均有两种表型，藏羊中Es（+）的表型分布比率最高（0.9333），甘肃高山细毛羊最低（0.5666）；酒泉小尾寒羊Amy 2A的表型分布百分数高达0.5333，藏羊最低，仅为0.2143；Amy 1、Amy 3和Cp基因座呈现出单态。藏羊和小尾寒羊中均检测出五种LDH同工酶，甘肃高山细毛羊和蒙古羊中分离出四种；藏羊和蒙古羊中存在五种POD同工酶，小尾寒羊和甘肃高山细毛羊具有四种POD同工酶。根据同工酶位点的有效等位基因数和多态基因座百分数可知：两小尾寒羊群体的有效等位基因最高，蒙古羊和甘肃高山细毛羊次之，藏羊最低；各绵羊品种（群体）的多态基因座百分数相同，均为40.00％。Nei氏平均基因杂合度和相对Shannon信息量对各绵羊品种（群体）的群体内遗传变异估测结果一致：两小尾寒羊群体均有较高的平均基因杂合度和相对信息量，藏羊则最低，蒙古羊和甘肃高山细毛羊居中。通过相对Shannon信息量的分析还可表明，各绵羊品种群体内的遗传变异主要由杂合体的连续存在所致，杂合体遗传变异在总遗传变异中占有主要地位。更多还原

【Abstract】 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(40.00％).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.更多还原