Factors influencing the prevalence of trypanosomosis in Orma Boran (trypanotolerant) and Teso zebu (trypanosusceptible) cattle crosses in Teso District, western Kenya

摘要

Theobjectiveofthisstudywastodeterminefactorsassociatedwithoccurrenceoftrypanosomosisinthefirstgeneration(F1)crossbredsbetweentrypanotolerantOrmaBoranandtrypanosusceptibleTesozebucattleinatrypanosomosisendemicareainTesoDistrict,westernKenya.Theoffspringwerescreenedfortrypanosomosisandotherhaemoparasitesusingparasitologicalmethods.Packedcellvolume(PCV),bodyweightsandtsetsedensity(FTD)werealsodetermined.Factorsconsideredintheanalysisincludedsex,age,bodyweightandseasonoftheyear.Generalizedlinearmixedmodels(GLMM)wereusedformultivariableanalysistoaccountforclusteringofobservationsattheanimallevelandestimateoutcomevarianceparameters.nbsp;Theoveralltrypanosomosisprevalencewas2.3%(n=477)probablycorrespondingtolowFTDinthearea(1fly/trap/day).Theriskoftrypanosomosisinfectionwashigherindrythanwetseason(OR=5.4)andinolderthanyoungeroffspring(OR=1.1).Thevarianceparametersobtainedindicatedthatvariationoftrypanosomosisprevalencelayonlyattheanimallevel.IntercurrenthaemoparasitesdetectedincludedAnaplasmamarginale,TheileriaandBabesiaspecies.nbsp;Overall,theresultssuggestedthatwhenthetsetsedensityisverylow,controloftrypanosomosisintheOrma-TesozebuoffspringinwesternKenyarequiretargetingofindividualaffectedanimalsinthedryseasons.