CryptosporidiumInfectioninDomesticGeese(Anseranserf.domestica)DetectedbyIn-situHybridizationS.Chvala,K.Fragner,R.Hackl*,M.Hess*andH.Weissenbo¨ckDepartmentofPathobiology,InstituteofPathologyandForensicVeterinaryMedicine,and*DepartmentforFarmAnimalsandHerdManagement,ClinicforAvian,ReptileandFishMedicine,UniversityofVeterinaryMedicine,Veterina¨rplatz1,A-1210Vienna,AustriaSummaryAnin-situhybridization(ISH)procedurewasdevelopedforthedetectionofCryptosporidiumsp.inparaffinwax-embeddedtissueswithadigoxigenin-labelledprobetargetingthe18SrRNA.Thistechniquewasusedinadditiontotraditionalmethods,suchashaematoxylinandeosinstaining,periodicacid-Schiffreaction,transmissionelectronmicroscopyandthepolymerasechainreaction,toexaminethebursaofFabricius(BF),conjunctivaandothertissuesfrom20domesticgeeseaged16–36daysforthepresenceofcryptosporidia.Positivesignalswerefoundtoamoderateormarkedextentinbothconjunctivalsamples(89%)andBFsamples(88%)butnotinothertissues.SequencingofthePCRamplificationproductrevealedidentitywithCryptosporidiumbaileyi.Theinfectedgeeseshowednoclinicalsignsandonlyscantyhistologicallesions.TheseresultsconfirmreportsshowingthatyoungwaterfowlareespeciallyvulnerabletocryptosporidiuminfectionandindicatethattheBFandconjunctivaarethepreferredsitesforthepresenceoftheprotozoon.ISHprovedagoodmethodfordetectingandidentifyingevensmallnumbersofcryptosporidiaintissuesections.q2005ElsevierLtd.Allrightsreserved.Keywords:Cryptosporidiumbaileyi;goose;parasiticinfectionIntroductionCryptosporidiaareprotozoanparasiteswithinthephylumApicomplexawhichdevelopinepithelialcells.Theyarepathogensofhumanbeings(Ungar,1990;Meadetal.,1999;Joachim,2004)andmanyothervertebratespecies(Jervisetal.,1966;Rehgetal.,1979;Tziporietal.,1981;Snodgrassetal.,1984;Bennetetal.,1985;Quilezetal.,1996;Fayeretal.,1997),andaretypicallyfoundinneonatalandyounganimals.Infectionmaybesymptomless,butcryptosporidiahavefrequentlybeenassociatedwithclinicalenteritis.Firstreportsofcryptosporidiainavianspeciesdatebackto1929(Ty...
