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猪繁殖与呼吸综合征病毒和猪圆环病毒2型共感染对猪体内病毒动态及免疫反应的影响 总被引：3，自引：0，他引：3
将猪繁殖与呼吸综合征病毒(PRRSV)、猪圆环病毒2型(PCV2)单感染和共感染6周龄健康仔猪,采用实时定量PCR(Real-time PCR)对血清、组织(心、肝、肺、肾、胰、脾、胸腺、扁桃体、腹股沟淋巴结、肠系膜淋巴结)中的PRRSV和PCV2载量进行检测,分别采用间接ELISA和间接IFA对血清中的PRRSV和PCV2特异性抗体进行检测,采用MTT法对猪外周血淋巴细胞(PBLC)的增殖能力进行检测.结果,PRRSV/PCV2共感染组血清、组织中PRRSV的载量均显著高于PRRSV单感染组,PCV2的载量均显著高于PCV2单感染组;共感染组PRRSV和PCV2特异性抗体阳转的时间均晚于并且效价均显著低于PRRSV或PCV2单感染组;共感染组和单感染组PBLC的增殖能力均受到抑制,其严重程度依次为:PRRSV/PCV2组>PRRSV组>PCV2组.由此表明,PRRSV和PCV2在猪体内对彼此的增殖具有促进作用;PRRSV和PCV2共感染对猪的免疫抑制具有加重作用. 相似文献
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猪瘟合并猪繁殖与呼吸综合征病毒(PRRSV)和猪圆环病毒2型(PCV2)感染 总被引：14，自引：5，他引：14
2004年初以来，杭州地区的几个规模化猪场陆续发生仔猪腹泻、保育猪呼吸困难的疾病，剖检见肺部呈橡皮样，全身淋巴结水肿，部分猪脾脏边缘梗死等，发病率、死亡率较高。设计针对猪繁殖与呼吸综合征病毒（PRRSV）、猪圆环病毒2型（PCV2）的特异性引物，进行RT—PCR或PCR检测；运用伪狂犬病（PR）鉴别试剂盒检测PR，运用免疫荧光法检测猪瘟（HC），并进行了细菌分离培养，通过全面检查认为，这几个猪场发生了猪瘟合并猪PRRSV、PCV2感染。 相似文献
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调查了曾经暴发沙门氏菌病的四个猪场的14头病猪,发现在这些猪的肿胀淋巴结中出现带有淋巴细胞排空的肉芽肿性炎症。应用免疫标记和PCR方法在病变部位检测到猪圆环病毒2(PCV2)抗原和PCV2DNA。此外,在这些病猪的肺脏中检测出猪繁殖与呼吸综合征病毒(PRRSV),分离到猪霍乱沙门氏菌。在9头沙门氏菌感染猪中,有5头为沙门氏菌、PMWS与PRRSV并发感染,其数量(55.6%)远远高于沙门氏菌与PMWS感染猪(22.2%)或沙门氏菌与PRRSV感染猪(22.2%)。 相似文献
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猪圆环病毒和猪繁殖与呼吸综合征病毒混合感染对仔猪致病性的评估 总被引：11，自引：0，他引：11
本研究通过猪圆环病毒2型(Porcine circovirus type 2,PCV2)和猪繁殖与呼吸综合征(Porcine reproductive and respiratory syndrome virus,PRRSV)强毒共感染3周龄健康仔猪来评价其致病性。试验动物随机分为3组,空白对照组(n=3头),PRRSV单独感染组(n=3头),PCV2和PRRSV共感染组(n=6头),从而比较相互之间的差异。通过临床症状、病理学变化、病原学和血清学检查,对二者混合感染仔猪的致病性进行了研究。结果表明PCV2和PRRSV共同感染能引起仔猪断奶后多系统消耗性综合征,表现为淋巴组织肿大、出血,肉芽肿性炎症,坏死性肝炎,仔猪消瘦、生长缓慢等特征性病变;混合感染能加重PRRSV对仔猪引起的间质性肺炎的严重程度。混合感染可以出现支气管肺炎和明显的肝病变,淋巴结多呈界限明显的块状出血等典型病变。 相似文献
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猪圆环病毒2型感染的检测与流行病学调查 总被引：8，自引：0，他引：8
根据GenBank上发表的PCV2 ORF2和PRRSV ORF7序列设计合成引物,建立分别用于检测PCV2和PRRSV的PCR和RT-PCR方法,并对2003年9月至2005年5月采自189个可疑发病猪场的389份病料进行了PCV2和PRRSV的检测。结果显示,来自33个猪场的35份样品为PCV2阳性,猪场PCV2阳性率为17.1%;PCV2与PRRSV混合感染率为5.1%,PCV2阳性猪场中PRRSV感染率为57.6%。流行病学统计结果表明,安徽省猪场PCV2阳性率最高;安徽省和广西省猪场PCV2和PRRSV的混合感染最严重;春夏季节PCV2阳性率明显高于秋冬;消瘦、被毛粗乱是PCV2感染的主要特征;淋巴结水肿或出血,肾脏肿大、出血或呈灰白色以及脾脏病变是PCV2感染的主要病理变化;仔猪7～8周龄发病率最高。 相似文献
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根据GenBark中登录的猪圆环病毒2型基因序列,应用PrimerPremier5.0设计筛选一对扩增ORF2基因引物,建立从猪病料中直接检测PCV2感染的PCR方法。扩增PCV2阳性样品出现一条447bp的特异性DNA条带,扩增产物测序结果证实为PCV2ORF2基因序列。应用本方法扩增猪瘟病毒(HCV)、猪繁殖与障碍综合征病毒(PRRSV)、猪伪狂犬病毒(PRV)、猪细小病毒(PPV)等常见猪病原均未出现特异性条带,表明方法特异;敏感性试验结果表明,样品DNA模板检测浓度可达到9.8×10-4ng/μL;重复性和稳定性试验结果表明,用本试验建立的PCR方法进行PCV2检测,结果稳定可靠。经病猪临床检测应用,在66份病猪样本中,PCV2感染阳性率为27.27%,且多与PRRSV、PRV、HCV、PPV等一种或多种病毒混合感染,混合感染比例达72.22%。 相似文献
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Ⅱ型PCV和PRRSV单独与共同感染未吃初乳猪病例人工复制 总被引：2，自引：0，他引：2
3周龄剖腹产不吃初乳(CD／CD)猪分别感染Ⅱ型猪圆环病毒(PCV—2)，猪繁殖—呼吸综合征病毒(PRRSV)，PCV—2和PRRSV共同感染，比较这些病毒的单独或联合作用。并于接种后不同日龄及猪濒死时剖检。接种后第10天(10DPI)，PCV—2和PRRSV共同感染猪出现严重的呼吸困难、昏迷，偶尔出现黄疽，10DPI后，91％死亡，20DPI时，全部死亡。PCV—2单独感染猪出现昏迷，散发性黄疽，42％出现渗出性皮炎，死亡率26％。PRRSV感染猪出现呼吸困难和昏迷，至28DPI时恢复。PCV—2感染猪和PCV—2／PRRSV共同感染猪皆出现与断奶后仔猪多系统衰竭综合征(PMWS)相同的组织病变。PCV—2／PRRSV共同感染猪亦出现严重的增生性间质肺炎和更相似的肝病变，出现极大量的含有PCV—2抗原的细胞。PRRSV感染猪出现中等程度的增生性间质肺炎，但未出现支气管或肝病变以及淋巴组织萎缩。研究结果表明：①PCV—2共感染能加重PRRSV对CD／CD猪引起的间质性肺炎的严重程度；②是PCV—2而不是PRRSV引起PMWS的淋巴组织萎缩，肉芽肿性炎症，坏死性肝炎等特征病变。 相似文献
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为查明某猪场病猪的死亡原因，对该场的典型病死猪进行病理剖检，无菌采集肺脏、肾脏、脾脏和淋巴结病料，提取核酸，进行荧光定量PCR检测和高通量测序，最后确诊该猪场的发病原因为PRRSV和PCV2的混合感染。对PRRSV和PCV2全基因组进行遗传进化分析，发现检测到的PRRSV属于VR2332-like亚群，与国内外26株参考毒株的核苷酸同源性为61.7%～99.8%;PCV2属于PCV2d基因型，与国内外31株参考毒株的同源性为54.7%～99.7%。 相似文献
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建立一种二重荧光LAMP的检测猪繁殖与呼吸综合征病毒(PRRSV)和猪圆环病毒(PCV)的快速诊断技术。根据已发表的PRRSV NSP2基因和PCV2 ORF2基因序列保守区域,分别设计并合成了两组针对PRRSV和PCV2序列的特异性引物和两条探针,两条探针分别标记不同的荧光基团,PRRSV-Probe 5’端标记FAM荧光基团,3’端标记BHQ1淬灭基团,PCV-Probe 5’端标记CY5.5荧光基团,3’端标记BHQ2淬灭基团。对组成反应体系中的引物、探针以及反应试剂进行优化,建立了二重荧光LAMP检测PRRSV和PCV2方法。对建立的方法进行特异性和敏感性测试,并用模拟混合样品和临床样品进行检测验证。结果显示,本研究建立的方法可以鉴别区分PRRSV和PCV2,特异性试验表明该方法只检测出PRRSV或PCV2,且与参试的对照病毒无交叉反应,特异性好。敏感性测试表明该方法最低检测PRRSV或PCV为100拷贝,敏感性好。对临床样品的检测,结果与荧光定量PCR方法检测结果一致。本研究建立的PRRSV和PCV2二重荧光LAMP检测方法,具有良好的特异性和敏感性,可用于临床样品中检测PRRSV和PCV2。 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