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中国地方猪种间的核型似近系数 总被引：6，自引：0，他引：6
计算了１６个中国地方猪种的核型似近系数，采用最短距离法进行了系统聚类。结果表明，各猪种间的核型似近系数在０．８９１３—０．９８７８之间，反映出中国猪种在核型上的高度稳定性和高度相似性。在核型上，华中型猪种更倾向于江海型；华南型更接近于西南型。 相似文献
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5个安徽地方猪种和5个引进猪种微卫星标记遗传多样性分析 总被引：2，自引：0，他引：2
采用30个微卫星DNA标记检测5个安徽地方猪种(定远猪、圩猪、安庆六白猪、皖南黑猪、皖南花猪)和5个引进猪种(巴克夏、杜洛克、皮特兰、大约克夏、长白)的等位基因,并进行了遗传多样性、F统计量、Nei's遗传距离和UPGMA聚类分析。结果表明,30个微卫星座位共检测到380个等位基因,10个猪种的遗传多样性丰富:有效等位基因数2.274 2~4.513 1,期望杂合度范围为0.496 3~0.777 7,多态信息含量范围为0.466 8~0.750 4,安徽地方品种的有效等位基因数、期望杂合度和多态信息含量均高于引进品种。5个安徽地方品种和5个引进品种的遗传分化系数变化范围分别为0.059 1~0.239 4和0.113 1~0.407 5。地方品种和引进品种的基因流平均分别为1.418 7和0.887 3。10个品种之间的遗传距离和遗传相似系数分别为0.341 4~1.628 6和0.196 2~0.710 8。聚类分析显示,5个地方品种和5个引进品种分别聚为一类,地方品种中圩猪和安庆六白猪首先聚为一小类,再与定远猪聚为一小类,皖南黑猪和皖南花猪单独聚为一小类,最后聚为地方品种类中;引进品种中,杜洛克与大约克夏首先聚为一小类,再先后与长白、巴克夏聚为一小类,最后与皮特兰聚在引进品种类中。该研究中30个微卫星座位在10个品种猪中具有丰富的遗传多样性,客观地反映了5个安徽地方品和5个引进品种的遗传关系和遗传分化,为地方品种资源的保护和利用工作提供科学依据,也为研究引进品种的多样性提供基础数据。 相似文献
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16种锦鸡儿属植物核型似近系数聚类分析 总被引：2，自引：0，他引：2
应用核型似近系数聚类分析方法研究我国16种锦鸡儿属植物的亲缘关系,并计算物种间的核型进化距离。结果表明:刺叶锦鸡儿(Caragana acanthophyllaKom.)与甘蒙锦鸡儿(C.opulensKom.)间核型似近系数最大(0.9979),核型进化距离最小(0.0177),亲缘关系最近;青海锦鸡儿(C.chinghaiensisLiou f.)与中亚锦鸡儿[C.tra-gacanthoides(Pall.)Poir.]间核型似近系数最小(0.3127),核型进化距离最大(1.1625),亲缘关系最远;核型分类结果与形态学分类结果并不相符。 相似文献
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为探究蒲公英属植物亲缘关系,本研究对13种蒲公英属（Taraxacum. F. H. Wigg.）植物进行了核型似近系数聚类分析,并计算了物种间遗传距离。结果表明：当核型似近系数接近0.6960时,13种蒲公英可以聚为4大类群;当核型似近系数接近0.4641时,13种蒲公英共属一类。异苞蒲公英与狭戟片蒲公英的亲缘关系最近,其似近系数最大,为0.9969,核型进化距离最小,为0.0031;多裂蒲公英和亚洲蒲公英的亲缘关系最远,似近系数为0.3343,核型进化距离为1.0959。本研究结果为蒲公英属植物的亲缘关系辨析、种质鉴定及物种进化分析提供依据。 相似文献
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对安徽省皖南花猪、皖南黑猪、定远猪、圩猪、安庆六白猪等五个地方猪种Ag-NOR s多态性进行了分析,结果显示Ag-NOR s均数分别为3.69、3.67、3.17、3.73、3.50,众数为4;2个引进品种大约克夏和长白Ag-NOR s均数分别为2.14、2.11,众数为2。Ag-NOR s均定位于10号和8号染色体次缢痕区。从研究结果可以推断皖南花猪和圩猪的品种纯度较高,聚类分析可将5个地方猪种分为2类:皖南花猪、皖南黑猪和圩猪为第1类,定远猪和安庆六白猪为第2类。此外5个地方猪种和2个引进品种Ag-NOR s多态性还为中国猪种起源于亚洲野猪,欧洲猪种起源于欧洲野猪提供了进一步的依据。 相似文献
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15种风毛菊属植物核型似近系数聚类分析 总被引：3，自引：0，他引：3
应用核型似近系数聚类分析方法研究了我国15种风毛菊属植物的亲缘关系,结果表明:长毛风毛菊与弯齿风毛菊核型似近系数最大(0.9788),核型进化距离最小(0.0215),亲缘关系最近;昂头风毛菊与小花风毛菊核型似近系数最小(0.7145),核型进化距离最大(0.3361),亲缘关系最远.核型分类结果与形态学分类结果并不完全相符,研究结果可为风毛菊属植物资源利用、分类学和系统演化等方面的研究提供一定的参考. 相似文献
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16种乌头属植物核型似近系数聚类分析 总被引：2，自引：0，他引：2
应用核型似近系数聚类分析方法研究了我国16种乌头属(Aconitum L.)植物的亲缘关系,并计算物种间的核型进化距离,以期为该属的分类提供一个新的重要指标。结果表明:卷毛蔓乌头(A. ciliare DC.)与弯枝乌头(A. arcuatum Maxim.)核型似近系数最大(0.9971),核型进化距离最小(0.0029),亲缘关系最近;狭盔高乌头(A. sinomontanum var.angustius)与松潘乌头(A. sungpanense Hand.-Mazz.)核型似近系数最小(0.3531),核型进化距离最大(1.0411),亲缘关系最远;在16种乌头属植物中,二倍体物种与四倍体物种表现出较远的遗传距离,核型分类结果与形态学分类结果并不完全相符。本结果将为乌头属植物资源利用、分类学和系统演化等方面的研究提供一定的参考。 相似文献
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3个地方鸡种的核型及其似近系数分析 总被引：7，自引：0，他引：7
运用外周血淋巴细胞培养法，对我国3个地方鸡种(仙居鸡、北京油鸡、狼山鸡)染色体核型进行了研究，结果显示：仙居鸡、北京油鸡、狼山鸡染色体形态十分相似，No．1、No．2、No．8、Z、W染色体都为m型；No．6染色体都为sm型；No．3、No．5、No．7、No．9染色体都为t型，仅在No．4染色体形态和W染色体的相对长度表现出一定的差异。此外，核型似近系数和进化距离聚类分析表明，7个地方鸡种(另收集了鹿苑鸡、寿光鸡、泰和鸡和旧院黑鸡的资料)可分为3个类群，其结果与起源进化，产地分布大致相同。 相似文献
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《养猪》2020,(4)
为做好地方猪种的保护和开发利用,对上海4个地方猪种梅山猪、浦东白猪、沙乌头猪和枫泾猪开展集中饲养测定试验,测定肥育性能、屠宰性能和肉质,并取样背最长肌测定氨基酸、脂肪酸和胆固醇。测定结果表明,4个地方猪种平均日增重和料重比分别为441.56 g和3.59,活体背膘厚和眼肌面积分别为38.63 mm和19.28 cm2,屠宰率和瘦肉率分别为67.98%和49.33%,总体上,4个地方猪种之间的差异不大,与引进的瘦肉型猪种比较,生长速度和产肉效率显著低。4个地方猪种的肌内脂肪含量明显高于杜长大商品猪,影响猪肉风味物质的脂肪酸和鲜味氨基酸优于杜长大瘦肉型商品猪。试验为指导开展地方猪种与引进品种杂交选育,生产出既具有地方猪产仔多、抗病力强、肉质优等优良特性,又兼备引进品种的生长速度快、料重比低、瘦肉率高的杂种商品猪,培育配套系或开发新品种,具有非常重要的现实意义。 相似文献
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Beran GW 《Preventive veterinary medicine》2008,86(3-4):198-207
When early people made their appearance, zoonotic infectious diseases were already waiting, but epidemic diseases did not appear in human history until people began to live in large numbers under conditions of close contact, mainly during the last 10,000 years. Disease has decimated urban populations, conquered armies, and disrupted society. The focus here is on (1) the plague of Athens and the Black Death; (2) smallpox, influenza, and rabies; (3) avian influenza prion diseases, and foot & mouth disease; and (4) emerging and re-emerging diseases. All have veterinary public health associations. In Athens, Greece, in 430 BC, when the Spartans ravaged the countryside, hordes crowded into Athens so that orderly movements, space in which to live, and adequate supplies of food became impossible. Crowding of any population fosters disease transmission; chaos and disorder enhance it all the more. Out of northern Egypt came a terrible plague from across the Mediterranean Sea. The identity of the plague of Athens remains unsure, but the well-considered conclusion is Rift Valley Fever, a mosquito borne, viral zoonosis. The Black Death, also called the Plague, raged in Asia for centuries. In 1347, the Black Death was brought by a ship out of Asia to Sicily. The scenes of devastation were repeated throughout Europe, with 90% or more of the people dying in city after city. Influenza, too, has been a cause of periodic human epidemics, but the great pandemic of influenza occurred in the last months of World War I. In the years of highest occurrence, more than half the world's population became clinically infected. If veterinary public health had been born earlier, it could have led to elucidating the epidemiology of influenza and the plagues of Athens, Europe, and Asia. In turn, smallpox had also caused continual tragedy. In 1796, Edward Jenner began to harvest pustules of cowpox from children or infected cows and inject them into susceptible children. In 1980, the World Health Organization declared that smallpox had been eliminated from the world. Rabies, though, still strikes terror. A number of animal diseases, broadly termed emerging and re-emerging diseases, need surveillance because they have the potential to impact human health. From late in 2003 to 2007, the highly pathogenic H5N1 influenza virus in poultry infected at least 121 people and caused 62 deaths in four countries. The prion diseases, too, all have very high numbers in concentrated contacts. To control these diseases, veterinary public health is essential, with diagnosis, epidemiological surveillance, clinical manifestations, and prevention as primary measures. 相似文献
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Dekker A Dercksen D Snoep J van Wuyjckhuise L 《Tijdschrift voor diergeneeskunde》2007,132(18):695-701
On 26th of july 2007 a new case of bluetongue was notified in the Netherlands and on 2nd of august 2007 foot-and-mouth disease was diagnosed in Surrey, England, which raised the threat of having both infections simultaniously in one area. Bluetongue and foot-and-mouth disease have a different pathogenesis, but symptoms may resemble each other at a later stage of infection. The pathogenesis and possible clinical symptoms of both infections are discussed and illustrated with pictures. 相似文献
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在动物的异常行为中以刻板行为最为常见,而咽气癖又是马最常见的口部刻板行为之一。作者就咽气癖在生理方面和心智方面对马体产生的影响、行为基础、诱因的研究进展及常见的防治措施进行综述。 相似文献
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近几年,世界饲用添加剂市场增长较快,预计今后将进一步增长,据世界粮农组织(FAO)首领会议的倡议,到2015年,将使世界营养不良的人口削减一半,其间,肉制品将会以每年2％的速度增长,特别是加快猪肉和禽肉增长。这将促进世界添加剂,尤其是蛋氨酸和赖氨酸需求量的增加。 相似文献
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