Seasonal Newcastle disease antibody titer dynamics in village chickens of Mbeere District, Eastern Province, Kenya

摘要

ThisstudywasconductedinMbeeredistrict,EasternProvinceKenya,toestablishNewcastle(ND)antibodytitrelevelsinhealthy,non-vaccinatedvillagechickenchicks,growersandadults,inwetanddryseasons.Inwetseason,allages,manybirdshadhighertitersincomparisontothedryseason.Therewas,thus,astatisticallysignificantdifference(p=0.05)betweenthetwoseasonswithadecreaseonthenumberofbirdswithprotectivetiterfrom100%(wetseason)to83%(dryseason).Theseresultsshowcontinuedendemicityofthediseaseinthearea.ReasonfornotbeingabletoisolatethevirusfromswabsandtissuesofthebirdsmaybepresenceofthehighNDantibodytiters;reducingtheviraltiterstolevelsnoteasilydetectablebytheserologicaltestused.(Meaningthatamoresensitivetestwasneededfordetection).Fromtheserologicalresults,therefore,itisadvisabletotargetvaccinationatthebeginningofthedryseason,soastoboostimmunityinthesebirds.