Multi-Drug Resistant Pasteurella multocida and Mannheimia haemolytica Strains Isolated from Different Hosts Affected by Pneumonic Pasteurellosis in Egypt

Pasteurella multocida (P. multocida) and Mannheimia haemolytica (M. haemolytica) are widespread pathogens, resulting in economically significant animal diseases. This study aimed to investigate some of the epidemiological aspects of P. multocida and M. haemolytica infections in Egypt, proper diagnosis of P. multocida and M. haemolytica infections, describe the distribution of capsular types of P. multocida isolates and measure the prevalence of multi-drug resistance in bacterial isolates recovered from cattle, buffaloes, sheep, and goats (ruminants) suffering from respiratory manifestations. A total of 155 deep nasal swabs were collected from 20 cattle, 37 buffaloes, 80 sheep, and 18 goats. Detection of 24 P. multocida and 12 M. haemolytica isolates from tested samples was carried out by bacteriological isolation, then identified by biochemical tests, and confirmed by polymerase chain reaction (PCR). The highest rate of infection with P. multocida and M. haemolytica has been found in young males (0-6 months age group). P. multocida capsular group A was found in the majority of the P. multocida strains (87.5%), while group D bacteria were identified in only three samples. Capsular groups B, E, and F have not been detected. The antimicrobial susceptibility pattern of P. multocida and M. haemolytica isolates indicated a high prevalence of multi-resistance to the majority of antimicrobials used as high resistance was detected against ampicillin, amoxicillin, penicillin-G, tetracycline, streptomycin, cefotaxime and chloramphenicol, however, 100% sensitivity was demonstrated by M. haemolytica isolates to gentamicin. Therefore, continuous monitoring of antimicrobial resistance is important to prevent the dissemination of resistant bacteria..