資源描述：
《冠狀病毒Coronavirusl論文-1990 Excretion and persistence of bovine coronavirus in neonatal calves.pdf》由會(huì)員上傳分享，免費(fèi)在線閱讀，更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫。
1、ArchVirol(1990)115:127-132VirrologyArchives@bySpringer-Verlag1990ExcretionandpersistenceofbovinecoronavirusinneonatalcalvesBriefReportSanjayKapilt,AvaM.Trent2,andSagarM.Goyal1Departmentsof1VeterinaryDiagnosticInvestigationandof2LargeAnimalClinicalSciences,Collegeo
2、fVeterinaryMedicine,UniversityofMinnesota,St.Paul,Minnesota,U.S.A.AcceptedJuly9,t990Summary.Followingoralinoculation,theexcretionofavirulentoranatten-uatedstrainofbovinecoronavirusincalffecesandtheirpersistenceinspiralcolon,ileum,andjejunumwerestudiedusinghemagglu
3、tinationanddirectfluorescentantibodytests,respectively.Theviruswasexcretedinfecesforonly3daysathightitersandthenintermittentlyatlowtiters.However,viralantigenwasdetectedincryptorPeyer'spatchesforatleast3weeksafterinfectionin1of3calvesgivenvirulentvirusand1of2calve
4、sgivenattenuatedvirus.Bovinecoronavirus(BCV)isanimportantcauseofdiarrheaincalvesof3-21daysofage[8].Thisvirusisknowntocauseamoreseverediseaseandhighermortalitiesthanthosecausedbythebovinerotavirusbecauseitmultipliesinboththesmallintestineandthelargeintestinewhereas
5、therotavirusinfectsonlythesmallintestine[12].Themainrouteofinfectionisthefecal-oralandthepregnantcowsarebelievedtobeimportantsourcesofvirusfornewborncalves.CowshavebeenreportedtobechronicexcretorsofBCV;thesheddingbeingexacerbatedinlatestagesofgestation,probablybec
6、auseofhormonalchangesandtheireffectsontheimmunesystem[1,2].AnattenuatedvirusvaccineisavailabletocontrolBCVdiarrhea,buthasnotbeenfoundtobeefficaciousinprotectingfrominfectionunderexperimentalconditions[3]orinthefieldincolostrum-fedcalves[11].Todeterminethereasonsfo
7、rvaccinefailure,informationisneededonthereplicationsites,titers,andpersistenceofBCVfollowinginfection.InformationisalsoneededonthemodeofpresentationoftheantigentotheimmunesytemaswellastheextentofmucosalimmuneresponsesengenderedbyBCV.128SanjayKapiletal.Saifetal.[9]
8、studiedthereplicationsitesofapneumoentericstrain(strainDB2)ofBCVincalvesof3-50daysofageandfoundthatthevirusmultipliedinthegutandtheupperrespiratorytract
