Caractérisation des souches de Mannheimia haemolytica circulant en France : lien avec les tableaux cliniques (respiratoire, septicémie ou pasteurellose aiguë chez les vaches laitières)

Résumé

107 strains of Mannheimia haemolytica isolated from cattle at LABOCEA Fougères were characterized : genotyping, serotyping, detection of LTx-encoding gene and antimicrobial susceptibility testing. Strains were mainly genotypes 2, serotypes A1 or A6, LTx-positive, reflecting their respiratory pathogenicity. Strains isolated from specific presentations as sepsis among calves and acute mannheimiosis from adult dairy cows seemed to present specific particularities : genotype 1/serotype A2 and genotype 2/serotype A6 respectively. Further investigations are needed to better understand if such bacteriological characteristics could explain such atypical clinical presentations. Antimicrobial susceptibilities were generally high, excepting for tetracyclin and streptomycin.