Ehrlichia chaffeensisEhrlichiaEhrlichia canisEhrlichiosisEhrlichia ruminantiumRickettsiaceaeRickettsiaceae InfectionsAnaplasmaDog DiseasesTicksAnaplasmataceaeIxodesTick-Borne DiseasesHeartwater DiseaseDogsHorse DiseasesTick InfestationsAnaplasmosisAntibodies, BacterialRNA, Ribosomal, 16SPolymerase Chain ReactionDNA, BacterialArachnid Vectors