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蜜蜂微孢子虫病(microsporidian disease)病原为蜜蜂微孢子虫(Nosema p.),是一种分布广泛的成年蜂病,为重要的检疫性病害。对感染蜜蜂微孢子虫病的越冬蜂进行研究发现,蜜蜂微孢子虫感染率与蜜蜂越冬安全关系密切,各组合实验蜂群蜜蜂越冬死亡率均为差异极显著(U检验,P0.01),即感染蜜蜂微孢子虫的蜂群,蜜蜂死亡率和饲料消耗量都明显高于对照组,且不同程度发生下痢症状。为蜜蜂微孢子虫的侵染机制研究提供理论数据,为进一步筛选功能基因奠定基础,从而推动我国特色蜜蜂产业健康快速发展。 相似文献
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本文叙述了国内外学者研究蜜蜂微孢子虫病的成果,包括:蜜蜂微孢子虫(Nosema apis)的生物学,发育周期,孢子虫病的流行规律及影响发病的因素,患病蜜的病理及孢子虫病的诊断防治。 相似文献
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蜜蜂孢子虫病是由蜜蜂孢子虫(Nosema Apis)寄生在蜜蜂成年蜂中肠粘膜细胞内引起的一种原虫病。感染孢子虫病的蜜蜂由于中肠粘膜受到破坏,失去正常消化机能,而造成机体衰弱,采集力下降,寿命缩短。蜜蜂孢子虫病,是西方蜜蜂的一种 相似文献
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蜜蜂微子虫病是世界性分布的成年蜜蜂传染病,对蜂群危害大。为寻找控制蜜蜂微孢子虫病的药物,对癸氧喹酯进行了的试验。将含癸氧喹酯2×10-6、1×10-5、5×10-5g/mL的蔗糖液,分别饲喂4天前就接种了东方蜜蜂微孢子虫(Nosema ceranae)的意蜂工蜂,连续喂药7d,再停药4天。试验结果表明,5×10-5g/mL的癸氧喹酯能显著降低工蜂的微孢子虫感染率(P<0.05),3种浓度的药物均能显著降低工蜂微孢子虫的感染程度(P<0.05);而药物对工蜂日均取食量、死亡率、中肠蛋白浓度、中肠葡萄糖苷酶相对酶活无显著影响(P>0.05)。 相似文献
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糖蛋白在免疫识别、信号转导等生命进程中扮演重要角色。为研究微孢子虫糖蛋白及其糖基化类型,采用比较基因组学方法对微孢子虫O-甘露糖糖基化通路进行分析。真核生物的O-甘露糖糖基化通路中有6种主要酶类,包括己糖激酶、磷酸甘露糖酶、GDP甘露糖磷酸化酶、Dol-P甘露糖合成酶、甘露糖转移酶、Dol-P甘露糖蛋白甘露糖转移酶。通过生物信息学方法分析家蚕微孢子虫(Nosema bombycis)、蜜蜂微孢子虫(Nosema ceranae)、兔脑炎微孢子虫(Encephalitozoon cuniculi)、肠脑炎微孢子虫(Encephalitozoon intestinalis)、比氏肠道微孢子虫(Encephalitozoon bieneusi)和柞蚕微孢子虫(Nosema antheraea)的这6种酶基因编码氨基酸序列特征及结构域类型,发现这些酶的垂直同源基因比较保守,多重序列比对表明在6种微孢子虫之间,6种酶的氨基酸序列相似性比较高,系统进化分析显示同属的微孢子虫多聚为一簇。研究结果表明,N.bombycis、N.ceranae、E.cuniculi、E.intestinalis和N.antheraea 5种微孢子虫的O-甘露糖糖基化的蛋白质修饰通路是完整、保守的,然而在E.bieneusi中,其关键酶Dol-P甘露糖蛋白甘露糖转移酶的氨基酸序列比较短,只有342个氨基酸,缺失了关键结构域PMT,因此可能无法完成O-甘露糖糖基化修饰。以上微孢子虫的O-甘露糖糖基化通路中6种主要酶的序列信息,为后续解析家蚕微孢子虫糖基化通路及对糖蛋白糖基化类型与功能的研究提供了线索。 相似文献
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蜜蜂孢子虫病属原生动物病害,它是由一种单细胞的蜜蜂孢子虫(Nosema apis)寄生在蜜蜂中肠上皮细胞内并在其中发育繁殖,消耗尽细胞营养后,便与坏死细胞一起脱落,然后随粪便排出体外,以孢子形态存活并进行重复感染。那么蜜蜂孢子虫在中肠细胞内引起的病理变化如何?围食膜的状况又是如何?依靠显微镜涂片是无法观察到 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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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
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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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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 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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家兔作为一种实验动物 ,推动了繁殖技术的发展。本试验通过对不同年龄公獭兔的睾丸进行组织学观察、测定 ,研究精子的发生规律 ,为系统地进行繁殖生理工作提供依据。1 材料与方法选 60日龄、75日龄、90日龄 3个年龄公獭兔各5只 ,用外科手术法摘取两侧睾丸 ,放入 Bouin氏液中固定 ,二甲苯透明 ,石蜡包埋 ,切成 5~ 8μm切片 ,H.E.染色。在显微镜下观察 ,并进行定量组织学指标测定及差异性比较。2 结果和讨论2 .1 睾丸定量组织学指标的测定结果 见表 1。表 1 獭兔睾丸定量组织学指标 μm,个 /精细管60日龄 75日龄 90日龄曲细精管… 相似文献
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Fractures of the anconeal process of 5 pigs ranging in age from 4 to 8 months were studied radiographically and histologically. Clinically, animals with a fracture of the anconeal process had a "tight," restricted gait. In pigs at 4.5 months of age, a radiolucent line through the base of the anconeal process was composed of fibrocartilage, fibrous connective tissue, and hyaline cartilage. Subperiosteal proliferation of woven bone was located along the cranial surface of the olecranon, adjacent to the base of the anconeal process. In older animals, the radiolucent line through the anconeal process contained variable amounts of fibrous connective tissue and fibrocartilage. The proliferation of subperiosteal bone at the base of the anconeal process formed a "buttress callus" which retained a radiolucent area between the callus and the proximal surface of the anconeal process. The latter region of radiolucency was continuous with the transversely oriented line that traversed the base of the anconeal process. 相似文献