Molecular Detection and Antibiogram Profiling of Pasteurella multocida Isolated From Breeder Chickens Suspected of Fowl Cholera in Gondar City, Ethiopia.

Fowl cholera is a highly infectious bacterial disease in poultry production. It is caused by Pasteurella multocida (P. multocida) and leads to significant health risks and financial losses. Therefore, this study is aimed at isolating, molecularly detecting, and analyzing the antibiogram of P. multocida from breeder chickens in Gondar City. A cross-sectional study design with purposive sampling was employed to collect a total of 130 tracheal swab samples from breeder chickens showing clinical signs of fowl cholera between January 2023 and December 2023, based on case availability. Bacterial isolation was performed using bacteriological and biochemical tests. The isolated P. multocida was confirmed through conventional polymerase chain reaction (PCR) using a capsular serotype-specific primer (capA). The antibiogram assessment of P. multocida against 10 antimicrobial agents was conducted using the Kirby-Bauer disk diffusion method. Descriptive statistics were used to analyze the isolation rate of the bacterium. Of the 130 sampled swabs, 10 (7.69%) tested positive for P. multocida in the phenotypic assay, and 3 (30%) of those isolates were positive for the hyaD/hyaC virulence gene. The study found that all three isolates were 100% sensitive to penicillin, ampicillin, norfloxacin, and florfenicol, while showing 100% intermediate sensitivity to streptomycin and 66.7% intermediate sensitivity to gentamycin, amoxicillin, tetracycline, trimethoprim/sulphamethoxazole, and kanamycin. The study confirms that P. multocida, the causative agent of fowl cholera in breeder chickens, is circulating in the area and exhibits varying antimicrobial sensitivity profiles.