Ovine Mannheimia haemolytica isolates from lungs with and without pneumonic lesions belong to similar genotypes
Artículo de investigación publicado en Veterinary Microbiology
1 de junio de 2018
This study investigated the genetic characteristics of 121 ovine Mannheimia haemolytica isolates from lungs with (n = 75) and without pneumonic lesions (n = 46) using multilocus sequence typing (MLST), virulence-associated gene typing and pulsed-field gel electrophoresis (PFGE). Twelve STs were identified with most isolates (81%) belonged to ST16, ST28 and ST8. Analysis of the M. haemolytica MLST Database indicate a wide distribution of these genotypes in small ruminants, never reported in bovine isolates. This could suggest the adaptation of certain genetic lineages of M. haemolytica to small ruminants. e-BURST analysis grouped most STs into three clonal complexes (CC2, CC8 and CC28), consistent with a clonal population structure of M. haemolytica. Virulence-associated gene typing identified five virulence profiles in 64% and 65.1% of the M. haemolytica isolates from lungs with and without pneumonic lesions, respectively. These data suggest that M. haemolytica isolates from the lungs with and without pneumonic lesions are genetically homogeneous. By PGFE analysis a high level of genetic diversity was observed not only within isolates from lungs without pneumonic lesions but also among isolates from pneumonic lesions (GD 0.69 and GD 0.66, respectively; P > 0.05). These results indicate that multiple strains of M. haemolytica may be associated with individual cases of pneumonia in sheep
Garcia-Alvarez A., Fernandez-Garayzabal JF., Chaves F., Pinto C. y Cid D.
Departamento de Sanidad Animal. Facultad de Veterinaria. Universidad Complutense (UCM). | |
Servicio de Identificación y Caracterización Microbiana (ICM). Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Universidad Complutense (UCM). | |
Departamento de Microbiología Clínica. Hospital Universitario 12 de Octubre. Salud Madrid. Comunidad de Madrid. | |
Universidad Nacional Mayor de San Marcos. | |