title: Identification, molecular characterization, and occurrence of two bovine hemoplasma species in Swiss cattle and development of real-time TaqMan quantitative PCR assays for diagnosis of bovine hemoplasma infections.
abstract: Concomitantly with an outbreak of fatal anaplasmosis in a cattle herd in Switzerland in 2002, we detected two bovine hemoplasma species in diseased animals: Mycoplasma wenyonii (formerly Eperythrozoon wenyonii) and a second, novel bovine hemoplasma species later designated "Candidatus Mycoplasma haemobos" (synonym, "Candidatus Mycoplasma haemobovis"). The second species was characterized by a shorter 16S rRNA gene. The aims of the present study were to provide a detailed molecular characterization of this species, to develop specific quantitative real-time PCR assays for the two bovine hemoplasma species, and to apply these assays in order to evaluate the prevalence and clinical significance of the hemoplasmas. Sequencing of the near-complete 16S rRNA gene of the second hemoplasma revealed that it was 94% identical to that of Mycoplasma haemofelis, an anemia-inducing feline hemoplasma species, but less than 85% identical to that of the bovine hemoplasma M. wenyonii. Using the newly developed assays, a total of 159 animals from the anaplasmosis outbreak were reexamined. In addition, we tested 57 clinically ill and 61 healthy Swiss cattle, as well as 47 calves. Both hemoplasmas were highly prevalent in adult cattle but occurred rarely in calves. Animals from the herd with the fatal anemia outbreak were more frequently infected with M. wenyonii and exhibited higher M. wenyonii blood loads than animals with unrelated diseases and healthy animals. Coinfections may increase the pathogenicity and clinical significance of bovine hemoplasmosis.
authors.affiliation: Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. mmeli@vetclinics.uzh.ch
authors.forename: Marina L
authors.initials: ML
authors.lastname: Meli
authors.forename: Barbara
authors.initials: B
authors.lastname: Willi
authors.forename: Ute M
authors.initials: UM
authors.lastname: Dreher
authors.forename: Valentino
authors.initials: V
authors.lastname: Cattori
authors.forename: Gabriela
authors.initials: G
authors.lastname: Knubben-Schweizer
authors.forename: Karl
authors.initials: K
authors.lastname: Nuss
authors.forename: Ueli
authors.initials: U
authors.lastname: Braun
authors.forename: Hans
authors.initials: H
authors.lastname: Lutz
authors.forename: Regina
authors.initials: R
authors.lastname: Hofmann-Lehmann
mesh_terms: D000818:Animals; D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D001431:Bacteriological Techniques / Q000379:methods*; D001769:Blood / Q000382:microbiology; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology*; D016000:Cluster Analysis; D015897:Comorbidity; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D008969:Molecular Sequence Data; D009174:Mycoplasma / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D009175:Mycoplasma Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013557:Switzerland
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S