Cryptosporidiosis: characterization of the infection in calves of dairy herds

摘要

Thecryptosporidiosisisacosmopolitanparasiticzoonosis.InArgentinatherewerestudiesin1989thatdescribedCryptosporidiumspp.likethecausalagentofneonataldiarrhoeafor69.7%ofthemilkroundups(Bellinzonietal1990).Thiscoccidiocolonizestheintestinalmicrovellosidadesthatisassociatedwithsignsofdiarrhoea,dehydrationandcólicos.Theaimsofthisworkaretocharacterizetheevolutionofthecryptosporidiosisfromthebirthto37-day-oldcalves;todescribetheagreementbetweennbsp;thepresenceofooquistesandthecharacteristicsofthefaecalmatterand,toconsiderthecowlikecontagionsource.Anexperimentwith15ArgentineHolandocalveswascarriedout,calveswererearedunderstandartfieldproductionconditions.Theyreceivedmilkysubstitute,commercialconcentrate,wateradlibitumandfreshforage.Dailythefaeceswereobservedclassifyingthemaccordingtotheirconsistency.nbsp;Faecalmattersamplesfromcalvesand13cows(motherofthecalves)between12and24hourspostcalvingwerecollecteddirectlyfromtherectum.ThesesampleswereusedtoobtainsmearswhereKinyouncolorationwasapplied.Asemi-quantitativeanalysisin25fieldsof40Xwasdone.nbsp;ThepositiveresultstoCryptosporidiumwereby77%ofthemothersand93.4%ofthecalves.Concerningthecalves,thehighestbothpercentageofpositiveandcountswereobservedinthesecondweekoflifeassociatedtosignsofdiarrhoea,nbsp;presenceofmucusandblood.Protozoariosatthefirstdayoflifeweredetected.Therefore,nbsp;attheperinatalmomentthemothersshowtheirconditionofcarriersandsourceofinfectionforthenewborncalffromthefirstdayoflife.And,thehighestincidenceofCryptosporidiumspp.associatedwiththediarrhealepisodeswasatthesecondweekoflife