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为了对湖羊的抗痒病选育提供实验依据,本研究采用PCR-RFLP和测序方法,对120只湖羊PRNP编码区136位、154位和171位密码子多样性进行检测,分析PRNP多样性和基因型对产羔数的影响,并对湖羊痒病易感性进行评估。结果表明,在湖羊中发现了之前研究报道的3个位点所有突变,其优势等位基因分别为A136(94.2%),R154(99.2%)和Q171(62.9%)。在检测的8种单倍型中,ARQ(56.6%)和ARR(21.3%)为主要单倍型。本研究还在湖羊中发现新的单倍型TRK(HM639758),但比例仅为0.4%。群体中ARQ/ARQ(29.2%)和ARR/ARQ(27.5%)为优势基因型,而抗病性基因型ARR/ARR仅占4.2%,未发现VRQ/VRQ基因型。湖羊主要隶属于抗病力较高的R1-2级(35.0%)和R3级(47.5%),推测湖羊对痒病具有中低度易感风险。PRNP不同基因型的选育对产羔数无显著影响。 相似文献
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试验旨在探究甘油二酯酰基转移酶（diacylglycerol acyltransferase 1,DGAT1）基因g.13504098 C>T位点、核受体辅抑制子1（nuclear receptor subfamily 6 group A member 1,NR6A1）基因g.11204707 A>C位点和α-甘露糖苷酶（alpha-mannosidase,MAN1A1）基因g.18795097 C>T位点的多态性与乌珠穆沁羊生长性状之间的关系,为高产乌珠穆沁羊分子选育提供新的遗传标记。运用Sequenom MassARRAY®SNP技术对乌珠穆沁羊DGAT1、NR6A1和MAN1A1基因的3个多态位点g.13504098 C>T、g.11204707 A>C和g.18795097 C>T进行检测,同时利用线性混合模型分析基因型与其4、6月龄生长性状的关联性。结果显示,在这3个位点中均检测到3种基因型,具体为：g.13504098 C>T位点的基因型为：CC、CT和TT,优势基因型为CC （0.49）,优势等位基因为C （0.70）;g.11204707 A>C位点的基因型为：AA、CA和CC,优势基因型为AA （0.54）,优势等位基因为A （0.73）;g.18795097 C>T位点的基因型为：CC、TC和TT,优势基因型为TC （0.51）,优势等位基因为C （0.55）。卡方检验显示,g.13504098 C>T、g.11204707 A>C和g.18795097 C>T位点在乌珠穆沁羊群体中均处于哈代-温伯格（Hardy-Weinberg）平衡状态（P>0.05）。群体遗传学分析表明,这3个位点在乌珠穆沁羊种群中属于中度多态性（0.25<PIC<0.50）。关联分析结果显示,g.13504098 C>T位点与乌珠穆沁羊4、6月龄的体重、体高、胸围、管围及6月龄的胸宽均呈极显著相关（P<0.01）;g.11204707 A>C位点与乌珠穆沁羊4、6月龄的体高、体斜长及4月龄的体重、6月龄的胸围均呈极显著相关（P<0.01）,与6月龄的体重、管围均呈显著相关（P<0.05）;g.18795097 C>T位点与乌珠穆沁羊4月龄的体高、6月龄的胸围均呈极显著相关（P<0.01）,与4月龄的体重、胸围以及6月龄的胸宽均呈显著相关（P<0.05）。综上所述,DGAT1基因g.13504098 C>T、NR6A1基因g.11204707 A>C和MAN1A1基因g.18795097 C>T位点多态性与乌珠穆沁羊群体部分生长性状具有显著的关联性,可以作为乌珠穆沁羊遗传选育的候选分子标记。 相似文献
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根据已报道的哺乳动物朊蛋白基因序列设计了1对引物，采用PCR方法扩增了16只非洲狮的朊蛋白基因，序列分析结果表明，所得到的非洲狮朊蛋白基因片段长678bp、编码226个氨基酸的前体蛋白，其核苷酸序列的同源性为99．79％以上，发现了4个核苷酸多态性位点，无氨基酸变异。经与已报道的猫、貂、绵羊、牛、鼠和犬等哺乳动物的氨基酸序列进行比较，与猫（AF003087，96．7％）和绵羊（96．2％）的氨基酸同源性最高。 相似文献
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为探究促甲状腺激素释放激素降解酶（Thyrotropin Releasing Hormone Degrading Enzyme,TRHDE）基因多态性与乌珠穆沁羊群体生长性状相关性，获得与生长相关的遗传标记，本研究以乌珠穆沁羊为研究对象，利用Illumina OvineSNP 600K BeadChip对TRHDE基因rs412113254A>G、rs419271398A>C、rs430108666C>A、rs417938979G>A位点进行基因分型，分析突变位点与生长性状的相关性。结果显示：TRHDE基因4个突变位点在乌珠穆沁羊群体中均检测出3种基因型，且均处于哈代-温伯格平衡状态（P>0.05）,rs412113254A>G位点在乌珠穆沁羊群体中属于低度多态（PIC<0.25）,rs419271398A>C、rs430108666C>A、rs417938979G>A位点均属于中度多态（0.25G位点可显著影响乌珠穆沁羊4月龄体重和胸围，可显著影响6月龄体重、胸... 相似文献
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试验旨在探讨哈萨克羊诱导型一氧化氮合酶（iNOS）基因多态性与布鲁氏菌病的相关性。使用虎红平板凝集试验（RBPT）方法对231只哈萨克羊血清进行布鲁氏菌病血清学检测,参考GenBank中绵羊iNOS基因序列,针对其第6、7、8外显子及其邻近内含子片段设计引物,利用PCR-SSCP技术和DNA测序技术对231只哈萨克羊的iNOS基因进行多态性检测,分析其SNPs与哈萨克羊布鲁氏菌病易感性的相关性。结果表明,67只哈萨克羊为布鲁氏菌感染阳性,阳性检出率为29.00%。在哈萨克羊iNOS基因的外显子6和8片段上未检测到多态位点,在外显子7片段上检测出F7-T18054C和F7-C18084T 2个多态位点,在F7-T18054C多态位点上检测到3种基因型（TC、TT、CC）,优势等位基因和基因型分别是C型和CT型,其等位基因频率和基因型频率分别是0.660和0.446。在F7-C18084T多态位点上检测到2种基因型（CT、CC）,优势等位基因频率和基因型分别是C和CC型,其等位基因和基因型频率分别是0.946和0.892。F7-C18084T属于低度多态（PIC<0.25）,F7-T18054C属于中度多态（0.25 < PIC < 0.5）。相关性分析表明,F7-T18054C和F7-C18084T多态位点与布鲁氏菌病易感性无显著相关性（P>0.05）。试验结果表明,哈萨克羊iNOS基因F7-T18054C和F7-C18084T多态位点与布鲁氏菌病易感性不存在相关性。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献