Investigating Mycoplasma wenyonii and Candidatus Mycoplasma haematobovis coinfection patterns and risk factors in cattle from southwestern France reveals strain-specific traits
Abstract
Hemotropic mycoplasmas (hemoplasmas) infecting cattle were first detected in France in 2019 during a clinical outbreak, but their prevalence both at the species and strain levels remains unknown. This study therefore aimed to determine the prevalence of hemoplasmas and their coinfections, and to identify associated risk factors using a fixed-effect logistic regression model. Detection was performed using 16S rRNA qPCR, as well as three strain-specific
rnpB
qPCR assays targeting
Candidatus
Mycoplasma haematobovis (CMh, formerly
Ca
. M. haemobos),
Mycoplasma wenyonii
strain Mexico (Mex), and
Mycoplasma wenyonii
strain Massachusetts (Mass). A total of 1011 cattle were sampled, of which 88.7% (897/1011) tested positive by 16S rRNA qPCR. Prevalence rates for CMh, Mex, and Mass were 67.7% (684/1011), 65.9% (666/1011), and 19.8% (200/1011), respectively. Concordance between 16S rRNA qPCR and strain-specific
rnpB
qPCR was 92% (931/1011). Coinfections were detected in 67.8% (565/833) of infected animals, with the CMh + Mex combination being the most frequent. The Mass strain was predominantly found in triple infections. Risk factors for infection included coinfections, age (except for Mass), and climatic conditions for CMh and Mass. Further studies are needed to elucidate transmission routes and pathogenicity mechanisms of hemoplasmas.