派普斯通应对PRRS的方法
供应商突发事件应对方法
供应商突发事件应对方法
引言
供应商突发事件是指在供应链管理过程中，出现的不可预测的突发情况，可能对供应商的正常运营和交付能力造成影响。
为了保障供应链的稳定性和持续性，企业需要制定相应的应对方法，以应对不可抗力的挑战。
应对方法
以下是供应商突发事件应对的一些常用方法：
1. 风险评估：企业应与供应商建立有效的风险评估机制，定期评估供应商可能面临的突发事件风险，并制定相应的应对计划。
这有助于提前发现潜在风险，并采取相应的措施来降低风险。
2. 多元化供应商：企业应建立多元化的供应商网络，降低对单一供应商的依赖性。
当一个供应商遇到突发事件无法正常供货时，可以及时切换到其他供应商，以确保正常的生产和交货。
3. 紧急联系机制：企业应与供应商建立紧急联系机制，确保在突发事件发生时能够及时沟通和协调。
这可以帮助企业了解供应商的情况，共同制定应对措施，减少供应链的影响。
4. 库存管理：企业应根据供应商可能遇到的突发事件，合理规划和管理库存。
这包括及时调整库存水平、增加关键物资的备货量等措施，以应对供应中断带来的影响。
5. 合同条款：企业在与供应商签订合同时，应考虑包含合适的突发事件条款。
这些条款可以规定应对突发事件的责任和义务，包括如何进行赔偿、缩短交货期等规定，从而保护企业的利益。
结论
供应商突发事件应对方法是企业维护供应链稳定的重要措施。
通过经过风险评估、多元化供应商、建立紧急联系机制、合理库存管理以及合适的合同条款，企业可以在突发事件发生时迅速应对，降低对供应链的影响，确保正常的生产和交货。
危机管理的四个关键点
危机管理的四个关键点企业危机来自方方面面，产品质量、劳资纠纷、对手竞争、财务问题，甚至企业高层问题都有可能导致危机发生，从而影响企业正常的发展。
当危机蔓延开来，产品滞销、渠道受阻、投资者抛售股票、媒体负面新闻铺天盖地。
人人皆知，意味着企业必须去马上展开公关沟通，尽可能消除和承担由此带来的各种质疑和损失。
公关危机中，怎样有序地进行危机管理？危机管理过程中要注意哪些关键问题？笔者从企业公关危机的传播路径，即危机管理的4个节点和阶段（prevention/preparation/Response/Recovery简称“ppRR”），略作阐述，和大家共同切磋。
第一节点：危机预防（prevention）prevention is better than cure（预防胜于治疗）。
这是医生经常告诫病人的一句话，古人也有一句经典的话“防患于未然”，都是讲事先预防和警觉的道理。
对危机进行预防，可以有效防止危机的产生、从而阻止危机的蔓延，最终控制危机，化解危机。
对企业来说，危机预防首先应该是一种战略思想，缺乏危机感的企业只能苟且一时，当遭遇政策调控、市场变化、对手挑衅和媒体诋毁等众多挑战时，往往茫然失措，甚至一蹶不振、丢盔卸甲，那时叫天天不应，叫地地不灵。
危机意识的建立应该从上到下、贯穿到企业发展的每一个方面。
很多优秀的企业这方面具有预见性，如深圳华为公司，几年前其总裁就在书中表达了浓重的危机意识，“华为总会有冬天，在冬天没有来临前，我们要准备好棉衣”。
高层管理者作为企业的掌舵者，高屋建瓴，从战略层面看待企业的每一步发展，洞悉市场的千变万化，这是一个优秀的企业必须具备的素养。
波音是大家熟知的一个大公司，如何使波音全体员工树立危机感？他们的人力资源部在新员工进入公司的那一时刻，就开始对他们进行危机意识的培养了。
新员工到岗的第一天，不会叫他们马上开始工作，而是集中在会议室看录像。
当主持人走上讲台对新进员工表示祝贺后，接着就放一段视频，片子是模拟波音公司倒闭的场景，那天，天气灰暗，波音公司所有的员工和管理者走出工厂车间、办公室和实验室，垂头丧气，耷拉着脑袋，广播里传出“今天是波音公司的最后一天，波音公司倒闭了”的声音，当人群走出波音厂区大门，他们看到一块醒目的的大牌上写着一行字：“波音公司的最后一块厂房等待出售！”所有看到这个震惊消息的波音人唏嘘万分，无语凝噎。
创造性问题解决(CPS)模式
14.4 创造性问题解决（CPS）模式在众多的问题解决模式中，纽约州立大学水牛城分校创造力中心所发展的创造性问题解决模式（CPS），算是相当周延的。
创造性问题解决模式(Parnes,1967),除了以系统的方法来解决问题外,特别强调问题解决者在选择或执行方案之前,应尽可能想出各种多样的解决方法。
创造性问题解决模式盖分为六个步骤,分别是:发现事实、发现问题、发现构想、发现解决途径、寻求接受。
每个阶段又分为扩散性思考与聚敛性思考两阶段。
兹将创造性问题解决过程六个阶段简介如下:(一)发现困惑指困惑的发现在扩散阶段应该尽可能将过去的经验、角色,从目前的机会中放开出来;在聚敛阶段应该接受各种挑战,作有系统的努力,尽量反应出问题的情形。
(二)发现事实指事实发现在扩散阶段应该广泛搜集资料,由许多不同的消息及观点来审视问题的情境;在聚敛阶段应该将大部分重要资料做出定义及分析。
(三)发现问题指问题的发现在扩散阶段应该对主要问题及次要问题做出各种可能的陈述;在聚敛阶段应该将一个工作的问题陈述出来。
(四)产生想法指想法的产生在扩散阶段应该对问题的陈述发展出很多的可能选择;在聚敛阶段能选择较具有独创及实用的意见。
(五)寻求解决方法指解决方法的寻求在扩散阶段能列出可能的批判;在聚敛阶段能选择几个批判标准来加以评价,并且能让意见更好。
(六)寻求接受指接受的寻求在扩散阶段能考虑所有可能的帮助或支持,并且发展潜在的实行步骤;在聚敛阶段能面对部份证实的方案采取行动计划。
问题解决过程由于一般固有方式无法加以解决,必须产生新的反应,使问题解决过程圆满。
而创造性问题解决过程即是希望学习者在面对问题时,能跳脱问题的情境,从有别以往的知识、经验,作各种可能的反应,同时兼顾新奇性与实用性,以建立出具有创造性的问题解决方案出来。
不论信息再怎么发达,科技再怎么进步,问题解决终究需要人来加以主宰。
过去由于人力、物力、社会结构单纯,各种问题解决藉由一些既有经验、方法即可以加以解决。
蓝耳病阴性猪PRRSV攻毒试验结果及在血清驯化中的应用
72猪业科学 SWINE INDUSTRY SCIENCE 2016年33卷第10期对于猪蓝耳病(PRRS)的控制与净化，20多年来国内外有已经有多种方法和措施成功地应用于猪场，并取得一定的效果，但由于PRRSV 本身的特点，目前并没有一个普适的方法，各猪场只能根据自身特点，有选择性地采用适合本场的控制方法。
目前常见方法有采用空气过滤等生物安全措施保持猪场PRRS 阴性，疫苗免疫控制猪场PRRS 稳定或净化PRRS，也有常用血清驯化法控制与净化PRRS。
良圻原种猪场从2007年开始尝试血清驯化，2008年开始在后备猪采用血清驯化控制猪蓝耳病。
由于驯化用的PRRSV 不是固定不变的，有时会根据病毒测序结果，进行相应的更换。
为了解驯化用PRRSV 毒株的特点，特开展相应的试验：用不同剂量的猪蓝耳病毒对抗原抗体双阴性猪只（35日龄）进行攻毒，跟踪抗原及抗体消长情况，以便为后续的猪场PRRS 的血清驯化提供试验依据。
1 试验材料制备的PRRSV 阳性血清，2015年制备，公司内部保存；PRRS 抗原抗体双阴性猪，35日龄、来源良圻原种猪场PRRS 双阴性核心场；IEDXX PRRS 抗体检测试剂盒；ABI 7 500 FAST 荧光PCR仪，TAKARA PCR仪，Taqman 荧光定量PCR 成套试剂。
2 试验方法2.1 病毒稀释方法对病毒阳性血清用PBS 进行倍比稀释，使得每毫升血清稀释液所含原血清量为1 μL、0.2 μL、0.02 μL、0.002 μL、0.001 μL，经荧光定量PCR 分析，所含病毒拷贝数分别为20 000、4 000、400、40、20；每头猪只相应攻毒剂量为1 mL 血清稀释液。
2.2 攻毒方法每头猪只分别按相应量进行攻毒，如表1。
2.3 采血检测在攻毒后的第1、2、3、4、5、6、7、9、11、13、15、21天进行采血和检测。
3 试验结果3.1 攻毒前猪只PRRS 监测情况PRRS 双阴性猪只的检测情况如表2，说明试验动物是符合要求的。
PRRS
Porcine reproductive and respiratory syndrome virus as a vector:Immunogenicity of green fluorescent protein and porcine circovirus type 2capsid expressed from dedicated subgenomic RNAsYanlong Pei a ,Douglas C.Hodgins a ,Jiaqiang Wu a ,1,Siao-Kun W.Welch b ,Jay G.Calvert b ,Gang Li c ,Yijun Du d ,Cheng Song a ,d ,Dongwan Yoo d ,⁎aDepartment of Pathobiology,University of Guelph,Guelph,Ontario,Canada N1G 2W1bP fizer Animal Health,Kalamazoo,MI 49001,USA cInstitute of Animal Health and Husbandry,Chinese Academy of Agricultural Sciences,Beijing,China dDepartment of Pathobiology,University of Illinois at Urbana-Champaign,2001South Lincoln Ave,Urbana,IL 61802,USAa b s t r a c ta r t i c l e i n f o Article history:Received 31January 2009Returned to author for revision 3March 2009Accepted 31March 2009Available online 6May 2009Keywords:PRRSVReverse geneticsForeign gene expression vector Vaccine vector Nidovirus ArterivirusPorcine reproductive and respiratory syndrome virus (PRRSV)is the causative agent of PRRS,which is characterized by late-term abortions in sows and respiratory disease in young ing an infectious cDNA clone of North American PRRSV strain P129,the viral genome was engineered to transcribe an additional subgenomic RNA initiating between non-structural and structural genes.Two unique restriction sites and a copy of the transcription regulatory sequence for ORF6(TRS6)were inserted between ORFs 1b and 2a,yielding a general purpose expression vector.The enhanced green fluorescent protein (GFP)gene was cloned between the unique sites such that the inserted gene was transcribed from TRS2which was located upstream within ORF1b,while the copy of TRS6drives ORF2a/b transcription.Upon transfection of cells with this plasmid,PRRSV infection was initiated and progeny virus “P129-GFP ”was obtained.Cells infected with P129-GFP showed fluorescence and the inserted gene was phenotypically stable for at least 37serial in vitro passages.Subsequently,a capsid (C)protein gene was cloned from porcine circovirus type 2(PCV2)recovered from an outbreak of porcine multisystemic wasting syndrome (PMWS)and inserted into the PRRSV infectious clone vector,generating virus “P129-PCV ”.To determine the immunogenicity of the recombinant viruses,pigs were immunized intramuscularly with P129-WT (wild-type),P129-GFP,or P129-PCV2.By 5weeks post-infection,speci fic antibody responses to GFP and PCV2capsid were elicited.This is the first report of foreign gene expression using PRRSV from dedicated subgenomic RNAs and demonstrates the potential use of PRRSV as a vaccine vector for swine pathogens.©2009Elsevier Inc.All rights reserved.IntroductionPorcine reproductive and respiratory syndrome (PRRS)is an emerged and re-emerging disease in pigs.The disease was first recognized in Germany and the US almost simultaneously in the late 1980s and has since spread globally to most pork producing countries (Keffaber,1989;Ben field et al.,1992;Albina,1997).PRRS is characterized by abortions and mummi fied fetuses in sows,and respiratory distress with poor growth in young pigs.The disease is mild in gilts and boars,but the virus (PRRSV)persists in semen and thus can be transmitted widely by arti ficial insemination.Since its emergence,PRRS has become one of the most economically important diseases in the swine industry.Modi fied-live vaccines are available,but safety and limited ef ficacy areongoing concerns.No speci fic treatment is available for PRRS,and thus the economic losses are enormous.Numerous isolates of PRRSV representing many geographical regions have been sequenced,revea-ling the existence of two distinct genotypes of PRRSV:European (type I)and North American (type II).The two genotypes share overall sequence identity of 63%and differ antigenically as well as genetically (Nelson et al.,1993;Meng et al.,1995;Wootton et al.,2000).PRRS virus is an enveloped,single-stranded,positive-sense RNA virus belonging to the family Arteriviridae and along with the Coronaviridae family,forms the order Nidovirales .The PRRSV genome is approximately 15kb in size and includes the 5′cap structure and 3′polyadenylated tail (Sagripanti et al.,1986;Wootton et al.,2000).The genome consists of nine genes:open reading frames (ORFs)1a,1b,2a,2b,3,4,5,6,and 7.The 5′three-quarters of the genome consists of two slightly overlapping ORFs,1a and 1b,and they are translated directly from the genome-sense RNA.ORF1b is expressed as a fusion protein with ORF1a by a frame-shifting mechanism,and the ORF1a and ORFla/b proteins are auto-cleaved by viral proteases into at least 13cleavage products that are theVirology 389(2009)91–99⁎Corresponding author.E-mail address:dyoo@ (D.Yoo).1Current address:Shandong Key Laboratory of Animal Disease Control and Breeding,Shandong Academy of Agricultural Sciences,Jinan,Shandong,China.0042-6822/$–see front matter ©2009Elsevier Inc.All rights reserved.doi:10.1016/j.virol.2009.03.036Contents lists available at ScienceDirectVirologyj o u r n a l ho m e p a g e :w w w.e l s ev i e r.c o m /l o c a t e /y v i r onon-structural proteins Nsp1α,Nsp1β,and Nsp2through Nsp12.The Nsps are thought to be involved in genome replication and subgenome transcription(van Dinten et al.,1999;van Marle et al.,1999).The viral structural proteins are encoded by ORFs2a,2b,and3through7which are located downstream of ORFs1a and1b.These genes are expressed as a3′-coterminal nested set of subgenomic(sg)RNAs(de Vries et al., 1990).The5′untranslated leader sequences of the sgRNAs are derived from the5′end of the viral genome and fused to the body segments of the sgRNAs at conserved hexanucleotide motifs[5′UCAAC(U/C)3′] located immediate upstream of every transcription unit(de Vries et al., 1990;den Boon et al.,1996).The conserved hexanucleotide motif and poorly conservedflanking sequences form secondary structures in the sgRNAs that make up the transcriptional regulatory sequences(TRS)that are necessary for sgRNA formation(Pasternak et al.,2000).With the exception of sgRNA7,sgRNAs are structurally polycistronic but,with the exception of sgRNA2a/b,functionally monocistronic as only the5′most proximal gene of each sgRNA is translated.ORFs2a,2b,and3through7 code for GP2(glycoprotein2),E(envelope),GP3,GP4,GP5,M (membrane)and N(nucleocapsid)proteins,respectively,and they make up virion particles(Meulenberg et al.,1995).The recent development of infectious clones for PRRSV has allowed specific alterations of viral genomes and generation of mutant viruses(Yoo et al.,2004).However,manipulation of arterivirus genomes is complicated by the condensed organization of the viral genome.In the case of the European genotype of PRRSV,each gene overlaps slightly except for ORFs 1b and2a(Meulenberg et al.,1993),although the overlap of genes seems less important for virus replication and growth for equine arteritis virus (de Vries et al.,2000).For the North American genotype,structuralgenes Fig.1.Genomic organization of P129-WT,P129-GFP,and P129-PCV2.(A)Genomic organization and sequence of the region surrounding the ORF1b/ORF2junction of the unmodified “wild-type”P129strain of PRRSV(P129-WT).The boxed sequence indicates the core hexanucleotide of TRS2.Amino acids indicate translated sequences of polyprotein1a/b(ORF1b),the GP2protein(ORF2a),and the E protein(ORF2b).The initiation codons are indicated in bold,and the E protein sequence is italicized.Numbers in parenthesis indicate genomic sequence positions.Stars indicate translation stops.(B)P129-GFP.Unique AflII and Mlu I sites and a copy of TRS6were introduced into the non-coding region between ORF1b and ORF2a,creating expression vector pCMV-S-P129-1bMCS2.The GFP gene was amplified by PCR and inserted between the AflII and Mlu I restriction sites.(C)P129-PCV2.The PCV2 capsid gene was amplified by PCR and cloned between the AflII and Mlu I restriction sites.92Y.Pei et al./Virology389(2009)91–99also overlap with the exceptions of ORFs 1b and 2a,and ORFs 4and 5(Nelsen et al.,1999;den Boon et al.,1991;Snijder and Meulenberg,1998).Thus,the entire genome of the North American type PRRSV possesses only 4short non-coding regions:191nucleotides of 5′untranslated region (UTR),1nucleotide between ORF1b and ORF2a,10nucleotides between ORF4and ORF5,and 151nucleotides of 3′UTR upstream of the polyadenylation tail.The 5′and 3′UTRs contain genome replication and transcription signals,and therefore offer limited sites for gene insertion and manipulation.The presence of overlapping genes hampers mutational analysis of the N-and C-termini of the structural proteins and also makes it dif ficult to insert heterologous genes into the viral genome.In the present study,we used a genomic cDNA clone of PRRSV (Lee et al.,2005)to generate a vector for foreign gene expression from a dedicated subgenomic transcription unit inserted in the region between the structural and non-structural genes.The vector was used to express GFP in vitro and in vivo .The inserted gene was tolerated by the virus,stable for at least 37passages in cell culture,and induced antibodies to GFP in young pigs.Using this approach,we also generated a recombinant PRRSV expressing the capsid protein gene of porcine circovirus type 2(PCV2).PCV2is a small DNA virus in the Circoviridae family,with a genome ofonly 1.76kb.PCV2ORF1is essential for viral DNA replication (Mankertz et al.,1998;Fenaux et al.,2000),while ORF2encodes the capsid protein containing type-speci fic epitopes that are believed to be important for virus neutralization (Nawagitgul et al.,2000;Fenaux et al.,2004).Accumulating evidence suggests a major role for PCV2in postweaning multisystemic wasting syndrome (PMWS)and porcine dermatitis and nephropathy syndrome (PDNS)(Hasslung et al.,2005).These syndromes cause serious economic impacts in the swine industry today (Chae 2005).We showed the recombinant PRRSV P129-PCV2induced an anti-PCV2antibody response in immunized pigs in the presence of maternal antibodies to PCV2.Our vector construction may be applicable not only for PRRSV,but also for other members of the families Arteriviridae and Coronaviridae .ResultsDevelopment of PRRSV as an expression vector for GFPTo explore the possibility of developing PRRSV as a gene expression vector,the GFP gene was inserted between the stop codon ofORF1bFig.2.(A)Restriction patterns of P129-WT (lane 1),P129-GFP (lane 2),and P129-PCV2(lane 3)genomic clones generated by Sma I digestion.Fragments of 590bp,4736bp and 10,779bp are expected from all three clones.The fourth fragment varies in size depending on the gene inserted at the non-structural and structural gene junction.Relative to the P129-WT fragment (2787bp,lane 1),the GFP-containing fragment from P129-GFP is 766bp larger (3553bp,lane 2)and the PCV2capsid-containing fragment from P129-PCV2is 754bp larger (3541bp,lane 3).(B –E)Recovery of recombinant PRRSV foci from full-length genomic clones.(F)Integration of the GFP gene in P129-GFP viral genome.Genomic RNA was extracted from P129-GFP virus and digested with DNase I prior to reverse transcription.Without reverse transcription,no products were ampli fied from P129-GFP using ORF7-speci fic PCR primers P129-7F and P129-7R (lane 1)or primers P129-1bF and P129-2aR that span the insertion site (lane 2).With reverse transcription,primers P129-7F and P129-7R ampli fied the ORF 7fragment (534bp)from both P129-WT (lane 3)and P129-GFP (lane 4).Using P129-1bF and P129-2aR,a product of 766bp larger (lane 6)than the product from P129-WT (lane 5)was ampli fied from P129-GFP.(G)Integration of the PCV2C gene in PRRSV.Genomic RNA from P129-WT (lanes 9,10,12)and P129-PCV2(lanes 7,8,and 11)was ampli fied using primers P129-1bF and pared to P129-WT (lane 9)a product that is 754bp larger was ampli fied from P129-PCV2(lane 7).Using PCV2C gene speci fic primers PCV2-F and PCV2-R,the expected 497bp product was generated from P129-PCV2(lane 8)but not from P129-WT (lane 10).Using PRRSV ORF4-speci fic primers P129-4F and P129-4R,the expected 567bp product was ampli fied from both P129-PCV2and P129-WT (lanes 11and 12,respectively).93Y.Pei et al./Virology 389(2009)91–99and the start codon of ORF2a (Fig.1A).This non-coding region is extremely short,comprising only one adenosine nucleotide.The TRS associated with ORFs 2a and 2b (TRS2;TGAACC)is positioned 26nucleotides upstream from the start of ORF2a and is embedded in ORF1b.Upon insertion of GFP to the region,TRS2will drive transcription of the GFP gene instead of ORFs 2a and 2b.Thus,a synthetic TRS (TTAACC)with flanking sequences derived from TRS6was introduced 22nucleotides downstream of GFP and 17nucleotides upstream from the ORF2a start (Fig.1B).TRS6was chosen because RNA secondary structure suggested that it was shorter than other PRRSV TRS elements and because the distance between the copy of TRS6driving ORF2a/b and the authentic TRS6ensured that potential intramolecular homologous RNA recombination would result in a non-viable (ORF2-5deleted)virus.The PRRSV genomic clone containing GFP was designated P129-GFP,and the insertion was con firmed by restriction patterns (Fig.2A,lane 2)and sequencing.MARC-145cells were transfected with P129-GFP and the production of virus was monitored daily for development of cytopathic effect (CPE)(Figs.2B,C,D).CPE was observed 4days post-transfection and the development of CPE was one day slower than for P129-WT.After three consecutive passages,P129-GFP virus was re-examined for GFP sequence integration in the viral genome (Fig.2F).While ORF7ampli fication products were identical in size for P129-WT (lane 3)and P129-GFP (lane 4),1bF and 2aR primers produced a larger size product from P129-GFP (lane 6)than from P129-WT (lane 5).The larger product was the expected size for correct insertion of GFP gene intothe viral genome.Replication of P129-GFP was slightly slower than that of P129-WT at passages 1to 3.However,plaques were comparable in size and morphology for P129-WT and P129-GFP,and the titers at passage 3were 5×105plaque forming units (PFU)/ml and 1×105PFU/ml,respectively.Fluorescence was evident in P129-GFP-infected cells (Fig.3A),demonstrating the expression of GFP during infection.To examine the genetic stability of recombinant PRRSV,P129-GFP was passaged 37times in MARC-145cells and GFP expression was monitored by fluorescence microscopy.Individual plaques of 20formed by P129-GFP were randomly chosen and examined for fluorescence.The selected plaques were all positive for fluorescence (Table 1),and sequencing of the viral RNA con firmed stability of the insert (data not shown).This data showed the genetic stability of P129-GFP after serial passages in cell culture and the stable expression of GFP.It also demonstrates that the region between ORF1b and ORF2a is a suitable site for foreign gene insertion for PRRSV.This was the first demonstration of the use of a nidovirus as an expression vector wherein the foreign gene is inserted in the region between the non-structural and structural protein codingsequences.Fig.3.Expression of GFP or PCV2capsid protein by P129-GFP and P129-PCV2in MARC-145cells.(A)Live cells infected with P129-GFP passage 3;(B)live cells infected with P129-GFP passage 37;(C)uninfected cells;(D)P129-PCV2passage 3fixed and stained with PCV2-speci fic antibody conjugated with FITC at 48h post-infection;(E and F)P129-PCV2infected cells fixed and co-stained with PCV2-speci fic antibody conjugated with FITC (E)or GP4protein-speci fic monoclonal antibody 169(F).Table 1Stability of GFP expression in P129-GFP virus.Virus Titer (PFU/ml)GFP expressing plaques Passage 38.3×10e620positive/20plaques Passage 372.4×10e720positive/20plaques94Y.Pei et al./Virology 389(2009)91–99Construction of PRRSV expressing PCV2capsidPCV2is associated with porcine multisystemic wasting disease (PMWS,now termed PCVAD [PCV-associated disease])and porcine dermatitis and nephropathy syndrome (PDNS).PCV2is transmitted by the oro-nasal route and shed in the bronchial secretions and feces,thus the transmission route is similar to that of PRRSV.The capsid (C)protein is the major antigen able to elicit protective immunity against PCV2.Thus,using the PRRSV vector system described above,an additional recombinant PRRSV was constructed to carry the PCV2C gene.A 702bp C gene was cloned by PCR from a lung tissue positive for PCV2.Sequencing of the C gene showed 99–100%amino acid identity to published sequences available in the GenBank database.The P129-PCV2clone was constructed by inserting the C gene into PRRSV in the same way as the GFP gene insertion for P129-GFP (Fig.1C).The insertion of the C gene was con firmed by restriction digestion pattern (Fig.2A,lane 3)and sequencing.The P129-PCV2recombinant virus was recovered from MARC-145cells by transfection (Fig.2E),and the insertion of the C gene in the viral genome was con firmed by RT-PCR of the viral RNA (Fig.2G).The titer of passage 3virus was 2×105PFU/ml and the plaque morphology was indistinguishable from P129-WT.Infection of cells with P129-PCV2and staining with PCV2-speci fic antibody produced distinct fluorescence (Fig.3E),which shows the expression of the C protein by P129-PCV2.The capsid protein of PCV2is arginine-rich and normally shuttles into the nucleus during PCV2replication (Liu et al.,2001),and similarly,the PRRSV N has also been shown to localize in the nucleus and nucleolus (Lee et al.,2006;Pei et al.,2008).Thus,in cells infected with P129-PCV2,the synthesis of legitimate PCV2capsid should be evident by the translocation of capsid into the nucleus.Thus,the C protein expression by P129-PCV2was con firmed by co-staining of virus-infected cells with PRRSV N protein-speci fic antibody and PCV2-speci fic antiserum (Fig.4).While the PRRSV N protein was found in the both cytoplasm and the nucleolus as usual (panel A),the PCV2capsid protein was speci fically localized to the nucleus and nucleolus (panel C)in the same cell,clearly demonstrating the expression of PCV2capsid protein by the recombinant PRRSVP129-PCV2.Fig.4.Co-expression of the PRRSV N protein (green)and the PCV2capsid protein (red)during infection of P129-PCV2.MARC-145cells were infected with P129-PCV2and stained 24h post-infection with PRRSV N-speci fic MAb SDOW-17(A and B)or PCV2-speci fic pig serum (C and D).Arrows indicate the PRRSV N protein in the nucleolus (panel A)in addition to the cytoplasm and the PCV2capsid protein in the nucleus and nucleolus (panel C).Panel E shows the merge of A and C.Panel F shows the merge of B and D.Table 2PCR primers and their genomic Sequence (5′–3′)aGenomic position b PurposePCV2-F cacggatattgtagtcctggt 1093–1114PCV2PCR test PCV2-R ccgcaccttcggatatactgtc1565–1586PCV2PCR testPCV2-orf2F gatgcttaagatgacgtatccaaggtggcg 1715–1734PCV2ORF2ampli fication PCV2-orf2R gtacacgcgtcattaagggttaagtcccccc 1031–1050PCV2ORF2ampli ficationP129-F1F aacagaagagttgtcgggtccac11,699–11,721P12911,783–12,055,ampli fication P129-F1R gctttcacgcgtccccacttaagttcaattcaggcctaaagttggttca 12,031–12,055Introduction of A flII and Mlu IP129-F2F gcgacgcgt gttccgtggcaacccctttaaccagagtttcagcggaaga atgaaatggggtctatacaaagcctcttcgaca 12,056–12,089P12912,056–12,697,ampli fication and introduction of Mlu I and TRS6P129-F2R aacagaacggcacgatacaccacaaa 13,819–13,844P12912,056–12,679,ampli fication P129-7F tcatccgattgcggcaaatg 14,724–14,743P129ORF7ampli fication P129-7R agaatgccagcccatca 15,242–15,258P129ORF7ampli fication P129-4F gtttcacctagaatggctg 13,213–13,231ORF4ampli fication P129-4R ccccaacatacttgaacattc 13,750–13,770ORF4ampli ficationP129-1bF ggtgaggactgggaggattac 11,921–11,941ORF1b –ORF2a,region ampli fication P129-2aRcagtacgtagcattggaacc12,758–12,777ORF1b –ORF2a,region ampli ficationa Restriction sites are underlined.TRS6and surrounding sequences are indicated in bold.bGenomic positions for PCV2primers were based on GenBank accession AF027217.Genomic position for P129primers were based on GenBank accession AF494042.95Y.Pei et al./Virology 389(2009)91–99Infection of pigs and antibody responses to GFP and PCV2capsid protein To determine antibody responses to GFP and the PCV2capsid protein,pigs were immunized with the recombinant PRRS viruses.Fifteen PRRSV-free pigs at 4weeks of age were randomly allotted to 3groups of 5pigs each.Animals were immunized twice on days 0and 21by intramuscular injection of 5×105PFU per animal with either P129-WT,P129-GFP,or P129-PCV2.Following inoculation,the animalswere maintained for 5weeks for clinical observation and serum collection.Clinical signs of PRRS were minimal and comparable in all 3groups (data not shown).Mild clinical signs were not unexpected,since the infectious cDNA clone used in these studies was not attenuated.Tonsil samples were collected at necropsy on day 35and assessed by RT-PCR for the presence of PRRSV ORF7using primers P129-7F and P129-7R (Table 2)as well as the GFP and PCV2capsid inserts using primers P129-1bF and P129-2aR.All 15pigs were positive for ORF7,indicating infection and persistence of PRRSV in the tonsils.PCR products from the ORF1b/ORF2a junction were not detected in these tonsil samples,possibly due to the much lower molar ratio of ORF1b-containing RNA template relative to ORF7-containing RNA in infected cells.Alternatively,it is possible that the GFP and PCV2capsid genes might have been unstable in vivo and lost in the inoculated pigs over time.To examine antibody responses in these pigs,ELISAs were conducted for PRRSV,GFP,and PCV2C protein.All pigs produced good levels of antibodies to PRRSV (Fig.5A),and the antibody titers were comparable among groups.P129-GFP elicited speci fic antibodies to GFP,whereas pigs immunized with P129-PCV2or P129-WT were negative for GFP (Fig.5B).The GFP antibodies increased following first immunization,and the second immunization at day 21boosted the antibody response somewhat (Fig.5B).Similarly,antibodies for PCV2C protein were detected in pigs immunized with P129-PCV2(Fig.5C).In these pigs,however,PCV2antibodies were detected at day 0in all 3treatment groups and tended to wane over time.These antibodies likely represent maternal antibodies taken up in colostrum shortly after farrowing at the farm of origin and prior to experimental infection.However,an increase in anti-PCV2antibodies was observed at 28days in the P129-PCV2group only (Fig.5C)due to boosting effects from the second immunization at day 21.In contrast,anti-PCV2antibodies in the other two treatment groups waned gradually from day 0until at least until day 35.To further determine the speci fic antibody responses to GFP and the PCV2C protein,Western blots were conducted using sera from these pigs.Serum from the P129-GFP group was reactive with GFP (Fig.6A),consistent with the ELISA data (Fig.5B).Similarly,serum from the P129-PCV2group showed a strong reaction with C pro-tein (Fig.6B).Weaker reactions were observed using sera from the P129-WT and P129-GFP groups,consistent with the presence of maternalantibodies.Fig.5.ELISA showing induction of speci fic antibodies in sera from pigs inoculated with P129-GFP,P129-PCV2,or P129-WT viruses.(A)antibodies to PRRSV N protein;(B)antibodies to GFP;(C)antibodies to PCV2Cprotein.Fig. 6.Western blots showing induction of speci fic antibodies in sera from pigs inoculated with P129-GFP,P129-PCV2,or P129-WT at day 0or day 35post-inoculation.Blots contain GFP protein (A)or PCV2virions (B).Arrows indicate positions of GFP and PCV2capsid protein.C denotes positive control (anti-GFP monoclonal antibody).M indicates molecular weight markers.The virus used to infect pigs that contributed to the serum pools is indicated above each lane.96Y.Pei et al./Virology 389(2009)91–99DiscussionThe primary target cell of PRRSV is the alveolar macrophage,and pigs are the only animal species known to be susceptible to PRRSV infection.Therefore,development of PRRSV as a vaccine vector would be useful for the delivery of porcine pathogen genes to the respiratory tract of the pig.Arterivirus genomes are organized in a complex way. Most genes overlap one another in different reading frames,making it difficult to engineer the genome for foreign gene insertion.An early approach involved engineering the3′terminal region of the N gene (Groot Bramel-Verheije et al.,2000).Modification of the3′terminal sequence of N gene was possible and caused only minimal effects on virus replication and growth.However,no more than7amino acids were inserted.More recently,Nsp2,a large product of proteolytic cleavage of the ORF1a and ORF1a/b polyproteins,was found to be remarkably heterogeneous in sequence,with several hypervariable regions.Therefore,the GFP gene was inserted in-frame into or between the hypervariable regions to create nsp2-GFP fusion proteins (Fang et al.,2006;Kim et al.,2007).This approach was successful and allowed for the production of recombinant viruses.However,in all cases the inserted GFP gene was not phenotypically stable and lost greenfluorescence after several passages in cell culture(Fang et al., 2006;Kim et al.,2007;Han et al.,2007).In the present study,we inserted GFP and the PCV2capsid genes into the short region separating the non-structural protein genes from the structural protein genes.In contrast to the nsp2-GFP fusion proteins described above,we expressed GFP as a separate transcription unit resulting in an additional sgRNA.This approach has the advantage of eliminating the need to alter the coding sequence of a viral gene,and also minimizes effects on expression and post-translational modification of viral gene products.As a result,our recombinant virus was stable for at least37cell culture passages without loss of the gene or the greenfluorescent phenotype.PRRSV is known to induce immune suppressive effects in pigs (Charerntantanakul et al.,2006)and can persist up to6months in infected pigs(Wills et al.,1997).For these reasons,co-infection of PRRSV with other pathogen such as PCV2can result in much more severe clinical outcome than either agent alone(Harms et al.,2001; Kim et al.,2003).Therefore,a dual-purpose vaccine capable of protecting pigs against both PRRS and PCV2would be advantageous. Our study demonstrates the potential of PRRSV as a viral vaccine vector.Prior to the purchase of animals for infection studies using P129-PCV2,all pigs were screened for PCV2by PCR.PCR is the gold standard for detection of PCV2,whereas antibody screening is not routinely conducted in diagnostic laboratories due to cross-reactivity between PCV2and PCV1which is ubiquitous and widely distributed in thefield (Magar et al.,2000).Although all pigs entering the present study tested negative for the presence of PCV2by PCR,antibodies were detected in sera collected on day0.These antibodies were most likely of maternal origin,since they decreased in concentration over the duration of the experiment in pigs receiving P129-WT or P129-GFP. Serological studies show that maternal antibodies for PCV2decay during thefirst2months of life(Rodríguez et al.,2002;Larochelle et al.,2003).Western blots and ELISA gave comparable results in this regard.In the current study,antibodies to PCV2only increased after day21of the study and did so only in pigs receiving P129-PCV2, suggesting that the increases were most likely specific responses to P129-PCV2vaccination.At the termination of the study(day35post-infection),tonsil samples in all3groups were positive for the PRRSV N gene by RT-PCR.The presence of the inserted GFP and PCV2genes in these same samples could not be confirmed using primersflanking the region of the gene insertion.No products were amplified,even from pigs infected with the P129-WT virus.Failure to amplify the ORF1b/ORF2a junction is likely the result of template RNA concentra-tions below the level of detection of the PCR assay,and is consistent with the observation that the copy number of ORF1b(present only on genomic RNA)is much lower than the copy number of ORF7(present on all sgRNAs as well as genomic RNA).In conclusion,a PRRSV gene expression vector was generated, capable of expressing a foreign gene from an additional transcription unit located in the region between the non-structural and structural genes of the virus.The recombinant PRRSVs expressing the GFP or PCV2capsid genes were generated and shown to replicate well in cell culture.The addition of766nt(GFP)or754nt(PCV2capsid)of foreign genetic material,representing approximately5%of the PRRSV genome,was tolerated with no evidence of compensatory deletions or rearrangements elsewhere in the genome.Pigs inoculated with these recombinant PRRSVs produced foreign gene specific antibodies.Our study demonstrates the potential of PRRSV to function as a vector for development of multivalent vaccines against swine diseases.Materials and methodsCells and virusesMARC-145African green monkey kidney cells(Kim et al.,1993) were maintained as previously described(Lee et al.,2003).Dulac porcine kidney cells,kindly provided by L.Babiuk(Vaccine and Infectious Disease Organization,SK,Canada),were grown in Modified Eagle's Medium(MEM)supplemented with5%fetal bovine serum (FBS;Gibco BRL),penicillin(100U/ml),and streptomycin(50μg/ml). Cells were maintained at37°C with5%CO2.Stocks of recombinant viruses derived from infectious clones were prepared by passaging three times on MARC-145cells.Titers of PRRSV were determined by standard plaque assays on MARC-145cells using6-well plates(35mm diameter)in duplicate.Plaques were stained with0.01%neutral red. For isolation of PCV2,lung tissues were obtained from a PCR-positive pig(Ontario18099)submitted to Animal Health Laboratory of the University of Guelph(Guelph,ON,Canada).The tissues were homogenized in PBS and thefiltrate was used to infect Dulac cells. At3days post-infection,cells were stained using a porcine circovirus hyperimmune serum(VMRD,Pullman,WA,USA)to confirm infection. On day4post-infection,cells were harvested and freeze–thawed three times.Cell debris was removed by centrifugation at5000×g, and the supernatant was stored at−80°C until use.Construction of a PRRSV expression vector and recombinant PRRSVsFor construction of the PRRSV expression vector,the regions flanking the ORF1b/ORF2a junction were amplified by PCR using the shuttle plasmid p2-7D4(containing genomic positions11,504to 15,395)as template.Two DNA products corresponding to positions 11,783to12,055and12,056to12,697were amplified.The primer set P129F1-F(containing an Eco47III site)and P129F1-R(containing AflII and Mlu I sites)was used for the upstream product(Table2).The primers set P129F2-F(containing Mlu I site and TRS6)and P129F2-R (containing a Bsr GI site)was used to amplify the downstream product(Table2).The twoflanking products were digested with Eco 47III–Mlu I and Mlu I–Bsr GI,respectively,and included in a three-way ligation with Eco47III–Bsr GI-digested full-length genomic cDNA clone pCMV-S-P129(Lee et al.,2003).The resulting construct pCMV-S-P129-1bMCS2contained a complete PRRSV genome with unique AflII and Mlu I sites and a copy of TRS6inserted between ORF1b and ORF2a.Transfection of MARC-145cells with this construct produced viable virus that replicated normally(data not shown).For insertion of foreign genes,pCMV-S-P129-1bMCS2was digested with AflII–Mlu I and ligated to either the GFP gene or the PCV2capsid gene into which AflII and Mlu I sites were introduced during PCR (Fig.1).Recombinant genomic clones were screened by Sma I digestion(Fig.2),and selected clones were sequenced to confirm the presence of insertions.The PCV2capsid protein gene was cloned97Y.Pei et al./Virology389(2009)91–99。
猪繁殖与呼吸综合症病原学基本特征
猪繁殖与呼吸综合症病原学基本特征猪繁殖与呼吸综合症（PRRS）是一种由猪繁殖与呼吸综合症病毒（PRRSV）引起的疾病。
该病毒属于科学家们刚刚发现的一类RNA病毒，被归类为科学家们所称的“新型冠状病毒”。
PRRSV主要通过接触污染物和空气传播途径传播，目前在全球范围内已经广泛存在。
PRRSV的基本特征1. PRRSV是一种RNA病毒，其基因组长度约为15kb。
2. PRRSV属于冠状病毒科，是一种单股正链RNA 病毒。
3. PRRSV具有高度变异性和复杂性，导致了其在不同地区和时间内出现了多种亚型和亚亚型。
4. PRRSV可以感染成年和幼年的生长期内的所有类型的肉用品种的家养或野生的豚鼠。
5. PRRSV可以引起多种临床表现，包括呼吸道、消化道、泌尿生殖系统、神经系统等方面的问题，并可能导致高死亡率和产能下降。
6. PRRSV的传播途径主要包括直接接触、空气传播和污染物传播。
7. PRRSV的病毒感染后，会引起机体免疫系统的抑制和损伤，从而导致机体对其他病原体的感染易感性增加。
PRRSV的繁殖特征1. PRRSV繁殖主要发生在宿主细胞内，其复制过程涉及到多个细胞因子和信号通路。
2. PRRSV可以通过与宿主细胞表面上特定蛋白质的结合来进入宿主细胞内部，并通过与宿主细胞内部的一些蛋白质相互作用来完成其生命周期。
3. 在宿主细胞内，PRRSV可以利用宿主细胞合成机制来合成自己所需的RNA和蛋白质，并将其组装成新的病毒颗粒进行复制和扩散。
4. PRRSV在宿主细胞中复制过程中，会产生大量的代谢产物，并可能导致宿主细胞死亡或损伤，从而进一步加剧PRRSV对机体免疫系统的影响。
PRRSV的防控策略1. 加强生物安全管理，保持动物场的清洁卫生，减少病毒传播途径。
2. 采取有效的隔离和检测措施，对疑似病例进行及时诊断和处理。
3. 推广疫苗接种，提高动物的免疫力，减少PRRSV感染和传播。
4. 加强监测和预警工作，及时发现和控制PRRSV的传播。
如何应对通货膨胀投资策略的调整与规避风险
如何应对通货膨胀投资策略的调整与规避风险如何应对通货膨胀投资策略的调整与规避风险在现代经济中，通货膨胀被视为一种普遍的经济现象，其带来的影响对于个人和企业在投资决策方面是非常重要的。
由于通货膨胀会削弱货币的购买力，因此，投资者需要调整其投资策略以应对通货膨胀的影响，并采取一些风险规避措施。
本文将重点探讨如何有效应对通货膨胀的投资策略调整及规避风险的方法。
一、保持多元化投资组合在面对通货膨胀时，保持多元化的投资组合是一种有效的策略。
多元化投资将资金分配到不同的投资类别中，如股票、债券、房地产和商品等，从而分散投资风险。
当通货膨胀发生时，不同类别的投资会受到不同的影响。
例如，股票通常在通货膨胀期间表现良好，而债券可能会受到贬值的风险。
通过多元化投资组合，投资者可以从不同投资类别中获得收益，以应对通货膨胀的影响，减少投资风险。
二、选择抗通胀的投资品种在通货膨胀时期，一些特定的投资品种通常会显示出抗通胀的特性。
例如，库存股票和大宗商品等资产通常会在通货膨胀时期保持价值。
这是因为大宗商品的价格会随着通货膨胀而上涨，而库存股票通常会在经济增长时期表现良好。
因此，投资者可以选择具有抗通胀特性的投资品种，以对冲通货膨胀带来的风险。
三、关注固定收益类资产在通货膨胀时期，固定收益类资产可以帮助投资者保值增值。
由于固定收益类资产的收益率是由合同或协议所规定的，与通货膨胀无关，因此这些资产可以提供稳定的现金流。
在通货膨胀加剧时，利率通常会上升，这将提高固定收益类资产的收益率。
因此，投资者可以通过增加固定收益类资产的比例来调整其投资组合，以规避通货膨胀的风险。
四、关注通胀保值的投资工具在通货膨胀期间，一些特定的投资工具可以帮助投资者保值，并实现资金的增值。
例如，通货膨胀保值债券是一种专门针对通货膨胀而设计的债券，其本金和利息会根据通货膨胀情况进行调整，从而保持其购买力不受通胀侵蚀。
此外，通货膨胀联结债券和通货膨胀保值型基金也是一些可以用来规避通货膨胀风险的投资工具。
闫之春：PRRS净化中的关键点
生 产 的猪 场 当 中尤 其是 在 有 母猪 群 、保 育 群和 育 肥群 的
猪场 ，母 猪 群是 阳 性 的 ，生 出的 小 猪母 源 抗体 是 阴 性 ， 母 源 抗 体 能持 续 到 断奶 后２～３ Ｎ 。 保育 舍环 境 当 中含 有
大量 的 病毒 ，没 有母 源 抗 体保 护 的保 育 猪往 往 在 断奶后
今 日养 猪 业 ： 用部 分清 群技 术 来 清除Ｐ Ｒ Ｒ ｓ 时，
最应 该 注意哪 些 关键环 节？
闰之春 ：１ ）清 空保 育 阶段 的猪群 ，把易 感动物 全部
清 走 ２ ）按 照相 关标 准规 范 ，消灭 环境 中的病 原体 ：清
闰之春 新希 望六和首席科 学家 扫 猪 舍一 定 要 高标 准 严要 求 ，做好 有机 物 的 清 除和 猪舍
８ ． ２ ． ４ 水
如 果是 使用地表 水源 的场 ，一定 要净化 消毒 ，进 行监 控 ，防止疾 病的传播 。所 以最好 的是 场里有 自己的水井 。 ８ ． ２ ． ５其他 载 体
饲 料 车 的风 险 不 大 ，只 要司 机 不 进猪 场 就 可 以 了 ； 工具 只 要是 没 进 过 其他 猪 场就 行 ；其 他 的动 物如 蚊 蝇 、 老 鼠等 都 几 乎 不 会 传 播 Ｐ ＲＲＳ Ｖ；饲 料 传 播 的 风 险 也很
８． ２ ． ２ 拉猪 货 车 拉 猪货车是 生物安 全的噩 梦 ，光靠 冲洗 不能真正 的杀
灭 病毒 ，美 国的做法是 用火 焰或红外 线探 头等 烘烤车辆 。
８ ． ２ ． ３ 人 员
进出场 内的员工要换 衣服 （ 包括鞋 、帽、外套 ），
严 格洗 澡 ，每年 接 种 流感 疫苗 ；防范 无 关 人 员 ，对 于 访 精液与 后备 猪 客一 定 要有 隔离期 。
prp操作流程及注意事项
prp操作流程及注意事项英文回答：PRP (Problem Reporting Process) is a systematic procedure followed to report and resolve any issues or problems that occur during a project or task. It is important to have a well-defined PRP in place to ensure effective communication, timely resolution, and continuous improvement.The PRP typically involves the following steps:1. Identifying the problem: The first step is to identify and define the problem or issue. This can be done through thorough analysis, observation, or feedback from team members or stakeholders.For example, let's say I'm working on a software development project and I notice that there is a bug in the code that causes the application to crash unexpectedly. Iwould identify this as the problem.2. Documenting the problem: Once the problem is identified, it is important to document it in detail. This includes capturing relevant information such as the symptoms, impact, and any other relevant data.In our example, I would document the bug by noting down the steps to reproduce it, the error messages displayed, and any other relevant information.3. Reporting the problem: The next step is to report the problem to the appropriate person or team responsible for addressing it. This can be done through various means such as email, issue tracking systems, or in-person communication.In our example, I would report the bug to the development team by creating a ticket in the project management tool we use.4. Analyzing and prioritizing the problem: Once theproblem is reported, it needs to be analyzed andprioritized based on its severity and impact on the project. This helps in determining the urgency and resourcesrequired to resolve it.In our example, the development team would analyze the bug and prioritize it based on factors such as thefrequency of occurrence and the impact on the application's functionality.5. Resolving the problem: After the problem is analyzed and prioritized, the next step is to resolve it. This involves finding the root cause, implementing a solution, and verifying its effectiveness.In our example, the development team would debug the code, fix the bug, and test the application to ensure that the issue is resolved.6. Communicating the resolution: Once the problem is resolved, it is important to communicate the resolution to the relevant stakeholders. This helps in keeping everyoneinformed and ensures transparency.In our example, the development team would update the ticket with the details of the resolution and notify the stakeholders about the fix.7. Learning from the problem: The final step in the PRP is to learn from the problem and implement preventive measures to avoid similar issues in the future. This can involve process improvements, training, or other corrective actions.In our example, the development team would conduct a post-mortem analysis to identify the reasons behind the bug and implement measures to prevent similar bugs in the future.Overall, the PRP is a crucial process in any project or task as it helps in identifying and resolving problems effectively. It ensures that issues are addressed in a timely manner, leading to improved quality and customer satisfaction.中文回答：PRP（问题报告流程）是一种系统的流程，用于报告和解决项目或任务中出现的任何问题。
PRRSV
些细 胞 假 定 为 Ｐ Ａ Ｍ ｓ 。 计数 结 果 显 示 ，在 ４组 试 验 中 的
会有肺泡巨噬细胞 （ Ａ Ｍ）和 中性粒细胞 （ Ｐ ＭＮ ｓ ）等清
除。当Ａ Ｍ 不 能清 除进 入 内部 的细 菌 时 ，Ｐ ＭＮ就会 在肺 泡 内聚 集来执 行 清除 任务 。 单核 一巨噬细 胞 是很 多微 生物 的靶 细胞 ，它们 能够 在 其细 胞 内生存 和复 制。 目前 已知 ，Ｐ Ｒ Ｒ Ｓ Ｖ能够在 单 核 细 胞 和 巨噬 细胞 内复 制 ，并 引起 二者 在 Ａ Ｍ 中 的百 分 比 下降 ，但 Ａ Ｍ 的 总量 不会 降低 。现 在还 没 有关 于 Ｐ Ｒ Ｒ Ｓ Ｖ 感 染 对 巨噬细 胞 清 除其 他 细菌 性 病原 如 副猪 嗜 血杆 菌 影 响 的研究 报 告 ，也 还缺 少 成 功地 说 明病 毒感 染 能 够 降低
药物 和疫 苗后 没 有 明显 的猪 只 死亡 ，但 猪 只 感染 副 猪 嗜 血杆 菌 的 问题 迟 迟得 不 到有 效解 决 。 对此 问题 ，笔 者 在 临床 处 理 中 除 了针 对 副猪 嗜血 杆
菌 这一 显 性感 染 外 ，还 对 猪场 隐性 存在 的蓝 耳 病病 毒 感 染进 行 了控 制 ，通 过 综合 应 用 此两 种 病 的 防控 措施 。在 很 多猪 场 解决 了副 猪 嗜血 杆 菌 的感 染 问题 。不过 根 据 笔
Ｐ Ａ Ｍ ｓ的 杀菌 功 能将 明 显下 降 。
关键词 ：Ｐ Ｒ Ｒ Ｓ Ｖ感 染：猪肺泡 巨噬细胞 ；副猪 嗜血杆菌
中 图分 类 号 ：Ｓ ８ ５ ２． ４ 文 献 标 识 码 ：Ｂ 文章 编号 ：１ ６ ７ ３ — ４ ６ ４ ５ （ ２ ０ １ ５ ） ０ ７ － ０ ０ ７ ７ － ０ ３