Molecular detection of Mycoplasma ovipneumoniae in ovine pneumonia and it’s role as a promoter of Mannheimia haemolytica co-infection

Abstract

Mycoplasma ovipneumonia is primarily a respiratory pathogen in sheep. It causes atypical pneumonia and predisposes animals to more severe secondary bacterial infections. This study investigated the presence of M. ovipneumonia in sheep showing respiratory affections using Polymerase Chain Reaction (PCR). Also, an association with Mannheimia haemolytica is assessed, as a co-infection. DNA extraction from 164 lung tissue samples of pneumonia affected sheep was done and screened by PCR with M. ovipneumonia specific primers. Nine samples were detected with M. ovipneumonia of which five of the samples were also positive to M. haemolytica. When the PCR data is compared with the post mortem findings, it is interesting to note that, co-infected cases showed more extensive lung damage with pulmonary consolidation and fibrinous pleuritic compared to those infected with M. ovipneumonia alone, demonstrating a synergistic effect. These findings suggest that M. ovipneumonia acts as a promoter pathogen which enables colonization and pathogenesis of secondary bacteria that lead to severe form of pneumonia. This study suggests that an early molecular detection of M. ovipneumonia might play a crucial role in timely prevention and treatment of respiratory disease outbreak in sheep flocks there by preventing economic losses to the sheep farmers.