Hemotrophic mycoplasma in Simmental cattle in Bavaria: prevalence, blood parameters, and transplacental transmission of ‘Candidatus Mycoplasma haemobos’ and Mycoplasma wenyonii

Abstract

BackgroundThe significance of hemotrophic mycoplasma in cattle remains unclear. Especially in Europe, their epidemiological parameters as well as pathophysiological influence on cows are lacking. The objectives of this study were: (1) to describe the prevalence of ‘Candidatus Mycoplasma haemobos’ (‘C. M. haemobos’) and Mycoplasma wenyonii (M. wenyonii) in Bavaria, Germany; (2) to evaluate their association with several blood parameters; (3) to explore the potential of vertical transmission in Simmental cattle; and (4) to evaluate the accuracy of acridine-orange-stained blood smears compared to real-time polymerase chain reaction (PCR) results to detect hemotrophic mycoplasma. A total of 410 ethylenediaminetetraacetic acid-blood samples from cows from 41 herds were evaluated by hematology, acridine-orange-stained blood smears, and real-time PCR. Additionally, blood samples were taken from dry cows of six dairy farms with positive test results for hemotrophic mycoplasma to investigate vertical transmission of infection.ResultsThe period prevalence of both species was 60.24% (247/410), C. M. haemobos 56.59% (232/410), M. wenyonii 8.54% (35/410) and for coinfection 4.88% (20/410). Of the relevant blood parameters, only mean cell volume (MCV), mean cell hemoglobin (MCH), and white blood cell count (WBC) showed differences between the groups of infected and non-infected individuals. There were lower values of MCV (P < 0.01) and MCH (P < 0.01) and higher values of WBC (P < 0.05) in ‘C. M. haemobos’-infected cows. In contrast, co-infected individuals had only higher WBC (P < 0.05). In M. wenyonii-positive blood samples, MCH was significantly lower (P < 0.05). Vertical transmission of ‘C. M. haemobos’ was confirmed in two calves. The acridine-orange-method had a low sensitivity (37.39%), specificity (65.97%), positive predictive value (63.70%) and negative predictive value (39.75%) compared to PCR.Conclusions‘Candidatus Mycoplasma haemobos’ was more prevalent than M. wenyonii in Bavarian Simmental cattle, but infection had little impact on evaluated blood parameters. Vertical transmission of the infection was rare. Real-time PCR is the preferred diagnostic method compared to the acridine-orange-method.

Detection of <i>Mycoplasma wenyonii</i> and “<i>Candidatus</i> Mycoplasma haemobos” from Japanese Black breeding cows in Kyushu and Okinawa region, southern part of Japan

“…In contrast, Niethammer et al . [ 15 ] found that 56.59% of Simmental cows were positive for CMh, while 8.54% and 4.88% were positive for Mw or mixed infections, respectively. The difference in the prevalence of the single species may be due to the difference in climate, which could favor vector-borne transmission, breed susceptibility, housing system (barn vs. pasture), or the age of animals [ 15 ].…”

“…Higher WBC levels in Mw-infected cattle than in CMh-infected and hemoplasma-negative cattle have been reported [ 26 ]. Additionally, higher WBC values have been found in CMh-infected and dual infected Simmental cattle [ 15 ]. The increased WBC levels observed in our study may be due to a consequence of a presumably strong stimulation of immunity by coinfection and consequently higher numbers of leukocytes [ 15 ].…”

“…Additionally, higher WBC values have been found in CMh-infected and dual infected Simmental cattle [ 15 ]. The increased WBC levels observed in our study may be due to a consequence of a presumably strong stimulation of immunity by coinfection and consequently higher numbers of leukocytes [ 15 ]. Furthermore, although the blood samples were collected from cattle without apparent clinical signs, lower RBC, HGB, and PCV levels and higher MCV levels than those in hemoplasma-negative cattle were found in CMh- [ 26 ], Mw-, CMh-, and co-infected cattle [ 29 ].…”

“…Furthermore, although the blood samples were collected from cattle without apparent clinical signs, lower RBC, HGB, and PCV levels and higher MCV levels than those in hemoplasma-negative cattle were found in CMh- [ 26 ], Mw-, CMh-, and co-infected cattle [ 29 ]. Lower MCV and MCH values and lower MCH values were observed in CMh- and Mw-infected cattle, respectively [ 15 ]. In this study, a hematologic difference was not found besides WBC values.…”

A comparative genomics and immunoinformatics approach to identify epitope-based peptide vaccine candidates against bovine hemoplasmosis

“…To date, M. wenyonii and Ca. M. haemobos have been described as major hemoplasmas that infect cattle worldwide [8][9][10]. In cattle, acute hemoplasma infections are rare but are characterized by anemia, fever, depression and diarrhea [11,12].…”