The Occurrence of Antimicrobial-Resistant <i>Salmonella</i> <i>enterica</i> in Hatcheries and Dissemination in an Integrated Broiler Chicken Operation in Korea
Ke Shang,
Bai Wei,
Se-Yeoun Cha,
Jun-Feng Zhang,
Jong-Yeol Park,
Yea-Jin Lee,
Hyung-Kwan Jang,
Min Kang
Affiliations
Ke Shang
Department of Veterinary Infectious Diseases and Avian Diseases, College of Veterinary Medicine and Center for Poultry Diseases Control, Jeonbuk National University, Iksan 54596, Korea
Bai Wei
Department of Veterinary Infectious Diseases and Avian Diseases, College of Veterinary Medicine and Center for Poultry Diseases Control, Jeonbuk National University, Iksan 54596, Korea
Se-Yeoun Cha
Department of Veterinary Infectious Diseases and Avian Diseases, College of Veterinary Medicine and Center for Poultry Diseases Control, Jeonbuk National University, Iksan 54596, Korea
Jun-Feng Zhang
Department of Veterinary Infectious Diseases and Avian Diseases, College of Veterinary Medicine and Center for Poultry Diseases Control, Jeonbuk National University, Iksan 54596, Korea
Jong-Yeol Park
Department of Veterinary Infectious Diseases and Avian Diseases, College of Veterinary Medicine and Center for Poultry Diseases Control, Jeonbuk National University, Iksan 54596, Korea
Yea-Jin Lee
Department of Veterinary Infectious Diseases and Avian Diseases, College of Veterinary Medicine and Center for Poultry Diseases Control, Jeonbuk National University, Iksan 54596, Korea
Hyung-Kwan Jang
Department of Veterinary Infectious Diseases and Avian Diseases, College of Veterinary Medicine and Center for Poultry Diseases Control, Jeonbuk National University, Iksan 54596, Korea
Min Kang
Department of Veterinary Infectious Diseases and Avian Diseases, College of Veterinary Medicine and Center for Poultry Diseases Control, Jeonbuk National University, Iksan 54596, Korea
Positive identification rates of Salmonella enterica in hatcheries and upstream breeder farms were 16.4% (36/220) and 3.0% (6/200), respectively. Among the Salmonella serovars identified in the hatcheries, S. enterica ser. Albany (17/36, 47.2%) was the most prevalent, followed by the serovars S. enterica ser. Montevideo (11/36, 30.6%) and S. enterica ser. Senftenberg (5/36, 13.9%), which were also predominant. Thirty-six isolates showed resistance to at least one antimicrobial tested, of which 52.8% (n = 19) were multidrug resistant (MDR). Thirty-three isolates (enrofloxacin, MIC ≥ 0.25) showed point mutations in the gyrA and parC genes. One isolate, S. enterica ser. Virchow, carrying the blaCTX-M-15 gene from the breeder farm was ceftiofur resistant. Pulsed-field gel electrophoresis (PFGE) showed that 52.0% S. enterica ser. Montevideo and 29.6% S. enterica ser. Albany isolates sourced from the downstream of hatcheries along the broiler chicken supply chain carried the same PFGE types as those of the hatcheries. Thus, the hatcheries showed a high prevalence of Salmonella isolates with high antimicrobial resistance and no susceptible isolate. The AMR isolates from hatcheries originating from breeder farms could disseminate to the final retail market along the broiler chicken supply chain. The emergence of AMR Salmonella in hatcheries may be due to the horizontal spread of resistant isolates. Therefore, Salmonella control in hatcheries, particularly its horizontal transmission, is important.
