Characterization of <i>Salmonella enterica</i> Isolates from Diseased Poultry in Northern China between 2014 and 2018

oleh: Jun Wang, Jinxin Li, Fengli Liu, Yongyou Cheng, Jingliang Su

Format: Article
Diterbitkan: MDPI AG 2020-02-01

Deskripsi

<i>Salmonella</i> infection not only causes acute and chronic diseases in poultry flocks, but the infected poultry are among the most important reservoirs for a variety of <i>Salmonella</i> serovars frequently transmitted to humans. This study aimed to investigate the occurrence of <i>Salmonella</i> spp. in local poultry farms in China. Samples (n = 4255), including dead-in-shell embryos, culled day-old-hatchings and 1- to 4-week-old diseased birds, were collected for <i>Salmonella</i> culture from broiler chicken, meat-type duck and pigeon farms in northern China between 2014 and 2018. A total of 103 <i>Salmonella</i> were isolated. <i>S.</i> <i>enterica</i> serovar Enteritidis and <i>S.</i> Typhimurium were the most prevalent serovars, representing 53.4% and 34.9% of the isolates, respectively. Serovar diversity was the highest in ducks, with the <i>S.</i> Apeyeme being isolated for the first time from duck tissues. All isolates were characterized by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). MLST showed that all <i>S.</i> Enteritidis isolates shared the same sequence type (ST11), and Typhimurium showed several rare STs in addition to ST19. In comparison, PFGE showed better discrimination for <i>S.</i> Enteritidis and <i>S.</i> Typhimurium isolates, with nine distinct pulsotypes being observed. The isolates exhibited varying degrees of resistance to 15 tested antimicrobials and identified <i>S.</i> Enteritidis isolates (98.18%) with multiple antimicrobial resistance were a cause for concern. Our data on invasive <i>Salmonella</i> infection in meat-type poultry in local farms can be used to identify sources and factors associated with <i>Salmonella</i> spread in poultry and the associated food chain.