The poultry roundworm Ascaridia galli has reappeared in hens kept for egg production in Sweden after having been almost absent a decade ...SkiptomaincontentAdvertisementSearchallBMCarticlesSearchDownloadPDFResearchOpenAccessPublished:20May2012PopulationgeneticstructureofAscaridiagallire-emerginginnon-cagedlayinghensJohanHöglund1,DavidAMorrison1,AnnieEngström1,PeterNejsum2&DésiréeSJansson3 Parasites&Vectorsvolume 5,Article number: 97(2012)Citethisarticle8781Accesses10Citations1AltmetricMetricsdetailsAbstractBackgroundThepoultryroundwormAscaridiagallihasreappearedinhenskeptforeggproductioninSwedenafterhavingbeenalmostabsentadecadeago.Todaythisisafrequentintestinalnematodeparasiteinnon-cagedlayinghens.Theaimofthisstudywastoinvestigatethegeneticdiversity(Fst)inA.gallicollectedfromdifferentpoultryproductionsitesinsouthernSweden,toidentifypossiblecommonroutesofcolonization.MethodsAdultparasites(n = 153)from10farms,includingbothbroilerbreederparentsandlayinghens,wereinvestigatedbyamplifiedrestrictionfragmentlengthpolymorphismanalysis(AFLP).WormsfromaDanishlayinghenfarmwerealsoincludedforcomparison.Mostofthefarmswererepresentedbywormsfromasinglehost,butontwofarmsmultiplesamplesfromdifferenthostswereassessedinordertostudyflockvariation.ResultsAtotalof97fragments(loci)wereamplifiedamongwhich81%werevariablealleles.Theaveragegeneticdiversitywas0.13(range = 0.09-0.38),whichiscomparabletootherAFLPstudiesonnematodesofhumanandveterinaryimportance.Within-farmvariationshowedthatwormsharbouredbyasingleheninaflockcoveredmostoftheA.galligeneticvariationwithinthesameflock(Fst = 0.01and0.03fortwofarms).Between-farmanalysisshowedamoderatepopulationgeneticstructure(Fst = 0.13),alongwithalowmutationalratebuthighgeneflowbetweendifferentfarms,andabsenceofstronggeneticselection.Networkanalysisshowedrepeatedgeneticpatternsamongthefarms,withmostwormsoneachfarmclusteringtogetherassupportedbyhighre-allocationrates.ConclusionsTheinvestigatedA.gallipopulationswerenotstronglydifferentiated,indicatingt