Isolation and molecular characterization of Mannheimia haemolytica and Pasteurella multocida associated with pneumonia of goats in Chhattisgarh

Aim: The purpose of this study was to isolate and characterize the Mannheimia haemolytica and Pasteurella multocida from blood, nasal discharge, and lung tissue of pneumonic goats. Materials and Methods: A total of 14 goats were investigated for pneumonic pasteurellosis. Of 14 goats, nasal swabs and blood samples were collected from 10 clinically diseased animals. Moreover, lung tissue and heart blood samples were collected during necropsy of four goats died with pneumonia. All the samples were processed for the isolation of M. haemolytica and P. multocida in the laboratory. Bacterial isolates were identified by cultural and biochemical characters and 16S rRNA sequence analysis. All the isolates were subjected to susceptibility testing using commonly used antimicrobials. M. haemolytica isolates were characterized by PHSSA gene detection. P. multocida isolates were characterized by KMT1 gene detection and capsule typing. Results: On necropsy of dead goats, the pneumonia was characterized as acute fibrinous bronchopneumonia. Bacterial culture revealed the isolation of M. haemolytica (7) and P. multocida (5) of 10 clinical cases. Moreover, M. haemolytica and P. multocida were coisolated from two of the lung tissues. Furthermore, one of the other two lung tissues showed the isolation of M. haemolytica while the other showed recovery of P. multocida. Bacterial isolates were specifically identified by the 16S rRNA sequence analysis. The isolates showed reduced susceptibility to beta-lactams, aminoglycosides, and fluoroquinolones. Moreover, the PHSSA and KMT1 genes were specifically detected among M. haemolytica, and P. multocida isolates, respectively. All P. multocida isolates belonged to serogroup A. Conclusion: The present study reported an occurrence of pneumonic pasteurellosis caused by M. haemolytica and P. multocida in a goat flock.