Occurrence of hemotrophic mycoplasmas in horses with correlation to hematological findings.

Hemotrophic mycoplasmas (HM) are small, cell wall-less bacteria and infections are known for a wide range of animals. One possible indication of equine HM infection was given in 1978, when a 'haemobartonellosis' outbreak was diagnosed in Nigerian horses by microscopy. However the first molecular proof of HM in horses was not reported until 2010, when a fragment of about 900 bp of the 16S rRNA of the equine HM was obtained. This sequence was used for the development of a SYBR green I real-time PCR assay specific for equine HM. The lower detection limit of the PCR was ten 16S rDNA copy numbers per ml of blood. The newly designed assay was successfully applied for the detection and quantification of HM in horses in Germany. A high sample prevalence of 26.5% (95% CI: 18.8-35.5%) was found (31 out of 117 horses). The mean bacterial load was 1.10×10(6) 16S rDNA copy number/ml blood (range: minimum 1.05×10(3), maximum 1.27×10(7)). Equine HM were also detected by microscopy (Giemsa and acridine orange stained blood smears), but results do not correlate very well with PCR results, as microscopy proved rather unspecific and not sensitive. In horses younger than one year, a significant correlation between PCR positive status and anemia was found. No correlation was found in PCR-positive animals older than one year. Therefore we assume that HM infection has a higher clinical relevance in young animals.

Detection of Candidatus Mycoplasma haemobos in cattle with anaemia.

Haemotrophic mycoplasmas are unculturable eperythrocytic pathogens that are found in a wide range of domestic and wild animals. In this study an outbreak of haemotrophic mycoplasmosis in cattle herds in Northern Germany is reported. Affected animals exhibited anaemia and depression and infection was confirmed following microscopic examination of blood smears and on PCR. Sequence analysis indicated that in addition to infection with Mycoplasma wenyonii, animals were infected with a novel bovine haemotrophic mycoplasma Candidatus Mycoplasma haemobos.

Haemotrophic Mycoplasma infection in horses.

Haemotrophic mycoplasmas (HM) are parasites on the surface of red blood cells and known to infect a wide range of animals. However, there are no previous evidences of HM infections in horses. In this study HM were detected for the first time in the blood of two horses suffering from poor performance, apathy, weight loss, and anaemia. Using a HM specific PCR assay and subsequent sequencing the infective agents isolated from the blood of said horses were confirmed as closely related to the HM species Mycoplasma haemofelis and 'Candidatus Mycoplasma haemobos'.

Occurrence of Mycoplasma suis in wild boars (Sus scrofa L.).

Porcine infectious anemia is a well-known disease that occurs worldwide and is caused by the uncultivable hemotrophic bacterium Mycoplasma suis. In this study the occurrence of M. suis in wild boars was investigated by employing a quantitative real-time LightCycler PCR. M. suis infections were detected in 36 out of 359 wild boars (10.03%). Sequencing of the 16S rRNA gene and subsequent phylogenetic analysis revealed the existence of two genetically distinct M. suis subtypes in the wild boar population: one subtype was >99.0% identical to known American and European M. suis isolates, and the second subtype showed the highest homology to known Chinese isolates. In summary, this is the first detection of M. suis in wild boars. The role of M. suis as pathogen in wild boars has yet to be established, but the present findings revealed a possible wildlife reservoir for these bacteria.