资源描述：
《冠状病毒Coronavirusl论文-1997 Infectious Bovine Rhinotracheitis, Parainfluenza-3, and Respiratory Coronavirus.pdf》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、BOVINERESPIRATORYDISEASEUPDATE0749-0720/97$0.00+.20INFECTIOUSBOVINERHINOTRACHEITIS,PARAINFLUENZA-3,ANDRESPIRATORYCORONAVIRUSSanjayKapil,DVM,PhD,andRandallJ.Basaraba,DVM,PhDBovinerespiratorydisease(BRD)complexiscausedbyavarietyofviral,bacterial,andfungalpathogens.EconomiclossesfromBRDintheUnitedSta
2、teshavebeenestimatedtobe$640millionannually,and46thisisamoreseriousdiseaseinstockerandweanedcattlethaninyearlingcattle.VirusescommonlyinvolvedinBRDareinfectiousbovinerhinotracheitisvirus(IBRV),bovineviraldiarrheavirus(BVDV),bovinerespiratorysyncytialvirus(BRSV),andparainfluenza-3(PI-3)virus.Bovine
3、respiratorycoronavirus(BRCV)isanemergingpathogencausingupperandlowerrespiratorytractdiseaseinfeedlotcattle,andclinicaldiseaseoccurswhentheanimalsarestressed,suchasduringshipment.48INFECTIOUSBOVINERHINOTRACHEITISRoleofIBRinBRDAsaresultofIBRVinfection,necrosisoftheepitheliumoftherespiratorytractcomp
4、romisesciliaryclearanceofbacteriaoftheupperThisworkwassupportedinpartbygrantstoSKandRJBfromtheKansasAgricul•turalExperimentStation.Thisispublicationnumber97-268-BfromtheKansasAgriculturalExperimentStation.FromtheDepartmentofDiagnosticMedicineandPathobiology,CollegeofVeterinaryMedicine,KansasStateU
5、niversity,Manhattan,KansasVETERINARYCLINICSOFNORTHAMERICA:FOODANIMALPRACTICEVOLUME13•NUMBER3•NOVEMBER1997455456KAPlL&BASARABArespiratorytract.Thisleadstoincreasedcolonizationandbacterialgrowthintherespiratorytractprecedingbacterialbronchopneumonia.Thevirusinfectionalsoleadstoinductionofavarietyofc
6、ytokines,someofwhichhaveantiviralactivity,suchasinterferons.Othercytokinesmaybebeneficialordetrimentaltofurthercolonizationoftherespiratorytractwithbacteria.Divalentcations,suchaszincandiron,areincreasedfollowingrespiratorytractinfectionwithviruses,andthesechangesinfluenceadherenceofthebacteria,pr
7、oductionofadhesins,andtheimmuneresponses,andfavorcolonizationofthelungsbybacteriaandsubsequentdevelopmentofpneumonia.Viralinfluencescanaltersurfactantandfibronectinproduction,andthusaffectbacterialcoloniza•tion.T
