本文選題：荷斯坦牛 + 牛白血病�。� 參考：《揚州大學(xué)》2016年碩士論文

【摘要】：牛白血病是由牛白血病病毒(BLV)引起的牛、綿羊等動物的慢性腫瘤性疾病,其特征是淋巴樣細(xì)胞惡性增生和高死亡率。牛白血病分布十分廣泛,存在于世界各個養(yǎng)牛國家,在某些牛群中血清陽性率甚至達(dá)到60%,是影響?zhàn)B牛業(yè)發(fā)展的重要傳染病之一。目前國外對牛白血病的研究較多,通過前人不斷研究已證明免疫系統(tǒng)在該病的發(fā)生及發(fā)病過程中起著重要作用。同時,CXCR1基因在奶牛炎癥和腫瘤的發(fā)生、增殖、生長等方面發(fā)揮重要的調(diào)控作用。因此,本研究通過對某大型奶牛場886頭中國荷斯坦牛血樣進(jìn)行采集,用BLV FRET-qPCR對牛白血病感染情況進(jìn)行檢測,同時收集采樣牛只生產(chǎn)性能測定記錄,采用多因素方差法分析白血病在不同產(chǎn)犢季節(jié)、測定季節(jié)、胎次和泌乳階段對奶牛泌乳性能(日產(chǎn)奶量、乳脂率、乳蛋白率、體細(xì)胞評分、總固體、尿素氮)的影響。同時,用直接測序法對奶牛CXCR1基因編碼區(qū)(CDS)突變進(jìn)行檢測,篩選出642GA、816CA、980GA和1068GA 4個SNP位點,再采用飛行時間質(zhì)譜法對篩查出的突變位點進(jìn)行SNP分型檢測,采用Logistic回歸分析CXCR1 SNPs基因型和單倍型與牛白血病的感染之間的關(guān)系,以期為牛白血病抗性的分子標(biāo)記輔助育種提供參考依據(jù),研究主要結(jié)果如下:1.在886頭奶牛中,患有牛白血病的牛為48頭,陽性檢出率為5.4%。2.白血病對不同產(chǎn)犢季節(jié)、泌乳階段、胎次及測定季節(jié)奶牛泌乳性能的影響都達(dá)到了極顯著水平(P0.01)。春季測定陽性牛乳脂率、SCS顯著低于陰性牛;泌乳中期陽性牛SCS顯著低于陰性牛,泌乳末期陰性牛乳脂率顯著高于陽性牛;三胎陰性牛尿素氮含量顯著高于陽性牛;夏、冬季節(jié)產(chǎn)犢的陰性牛SCS顯著高于陽性牛。3.CXCR1基因CDS區(qū)共發(fā)現(xiàn)13個SNP位點,經(jīng)連鎖分析分為4個連鎖群。從4個連鎖群中各選擇1個SNP位點進(jìn)行后續(xù)分析,分別是:642GA、816CA、980GA和1068GA4個SNP位點,利用飛行質(zhì)譜法對大樣本中國荷斯坦牛進(jìn)行檢測。CXCR1-642、CXCR1-816、CXCR1-980和CXCR1-1068 4個SNP位點優(yōu)勢基因型分別為GG、CC、GG和GG型,頻率分別為0.58、0.466、0.60和0.658,優(yōu)勢基因分別為G、C、G和G,基因頻率是0.76、0.69、0.78和0.81。4個SNP位點共有8種單倍型,其中單倍型GAAG頻率最高(0.819),而單倍型GCAG頻率最低(0.033)。CXCR1 980GA位點和單倍型GCAG對�；及籽〉南鄬︼L(fēng)險影響顯著(P=0.016)。980GA位點AA型基因的發(fā)生概率為GG型基因的5.04倍,CXCR1單倍型GCAG患牛白血病的風(fēng)險是GAGG的1.97倍。
[Abstract]:Bovine leukemia is a chronic tumor disease caused by bovine leukemia virus (BLVV) in cattle, sheep and other animals. It is characterized by malignant proliferation of lymphoid cells and high mortality. Bovine leukemia is widely distributed and exists in various cattle countries in the world. In some cattle, the seropositive rate even reaches 60%, which is one of the important infectious diseases affecting the development of cattle industry. At present, there are many researches on bovine leukemia abroad. It has been proved that the immune system plays an important role in the occurrence and pathogenesis of bovine leukemia. At the same time, CXCR1 gene plays an important role in the regulation of inflammation and tumorigenesis, proliferation and growth of dairy cattle. Therefore, the blood samples of 886 Chinese Holstein cattle in a large dairy were collected, the infection of bovine leukemia was detected by BLV FRET-qPCR, and the records of production performance of sampled cattle were collected at the same time. Multivariate variance method was used to analyze the effects of different calving seasons, birth order and lactation stage on milk performance (daily milk yield, milk fat rate, milk protein rate, somatic cell score, total solid state, urea nitrogen) in dairy cows. At the same time, direct sequencing method was used to detect the mutation of CXCR1 gene coding region in dairy cattle, and four SNP loci were screened out. The four SNP loci were selected, and the mutation sites were detected by time-of-flight mass spectrometry (TF-MS). Logistic regression analysis was used to analyze the relationship between CXCR1 SNPs genotype and haplotypes and bovine leukemia infection in order to provide reference for molecular marker assisted breeding of bovine leukemia resistance. The main results were as follows: 1. Of the 886 cows, 48 had bovine leukemia, and the positive rate was 5. 442. 2. The effect of leukaemia on milk performance of dairy cows in different calving seasons, lactation stage, birth order and determination season reached a very significant level (P 0.01). In spring, the milk fat rate of positive cattle was significantly lower than that of negative cattle, the SCS of middle lactation positive cattle was significantly lower than that of negative cattle, the milk fat rate of late lactating negative cattle was significantly higher than that of positive cattle, the urea nitrogen content of three-foetus negative cattle was significantly higher than that of positive cattle, and in summer, The SCS of calving negative cattle in winter season was significantly higher than that of positive cattle. 3. A total of 13 SNP loci were found in the CDS region of CXCR1 gene, which were divided into 4 linkage groups by linkage analysis. One SNP locus was selected from each of the four linkage groups for follow-up analysis, namely: 642 GAY816CAN980GA and 1068GA4 SNP loci. The dominant genotypes of CXCR1-642 CXCR1-980 and CXCR1-1068 were GGCCCCG and GG type, respectively, in large sample Chinese Holstein cattle by using flight mass spectrometry (FMS) to detect CXCR1-816CXCR1-980 and CXCR1-980, respectively. The frequencies were 0.58 and 0.4660.60, respectively, and the dominant genes were G and G, respectively. The frequencies of the genes were 0.766, 0.699, 0.78 and 0.81.4, respectively, and there were 8 haplotypes. The frequency of haplotype GAAG is the highest (0.819), while the frequency of haplotype GCAG is the lowest (0.033%). CXCR1 980GA site and haplotype GCAG have significant influence on the relative risk of bovine leukemia. The risk of bovine leukemia is 1.97 times higher than that of GAGG.
【學(xué)位授予單位】：揚州大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：S858.23
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本文編號：1909935