First detection of Mycoplasma wenyonii in France: Identification, evaluation of the clinical impact and development of a new specific detection assay.

•Mycoplasma wenyonii (Mw) has been identified in French cattle.•Milk drop, anemia, and edema of the lower limbs were noticed in sick cattle.•Prevalence of Mw bacteremia is about 5% in healthy cattle vs 25% in sick cattle.•A new PCR assay targeting polC is more specific than 16 s RNA amplification.•A new PCR assay targeting polC allows a one-step diagnosis without sequencing.