Abstract
The prevalence of Salmonella from chicken and pig slaughterhouses in Henan, China and antimicrobial susceptibility of these isolates to antibiotics was determined. From 283 chicken samples and 240 pig samples collected, 128 and 70 Salmonella isolates were recovered with an isolation rate of 45.2 and 29.2% respectively. The predominant serovars in chicken samples were S. enterica serovar Enteritidis, S. enterica serovar Hadar and S. enterica serovar Indiana, while those in pig samples were S. enterica serovar Typhimurium, S. enterica serovar Derby and S. enterica serovar Enteritidis. Resistance to ciprofloxacin was 8.6 and 10.0% for isolates from chickens and pigs respectively, whereas resistance to cefotaxime was 5.5 and 8.6%, respectively. Multidrug resistance (resistance to three or more classes of antimicrobial agent) was markedly higher in pig isolates (57.1%) than in chicken isolates (39.8%). Of particular concern was the detection of ciprofloxacin and cefotaxime co-resistant S. enterica serovar Indiana isolates, which pose risk to public health. All 16 S. enterica serovar Indiana isolates detected were resistant to ciprofloxacin, among which 11 were co-resistant to cefotaxime. The S. enterica serovar Indiana isolates accumulated point mutations in quinolone resistance determination regions of gyrA (S83F/D87G or S83F/D87N) and parC (T57S/S80R). Two plasmid mediated quinolone resistant determinants were found with aac (6')-Ib-cr and oqxAB in 16 and 12 S. enterica serovar Indiana isolates respectively. Cefotaxime-resistance of S. enterica serovar Indiana was associated with the acquisition of a bla CTX-M-65 gene. The potential risk of ciprofloxacin and cefotaxime co-resistant S. enterica serovar Indiana infection is a significant concern due to limited alternative treatment options. Reduction of Salmonella in chicken and pig slaughterhouses, in particular, ciprofloxacin and cefotaxime co-resistant S. enterica serovar Indiana will be an important measure to reduce the public health burden of Salmonella infections.
Highlights
Foodborne salmonellosis is an important public health problem worldwide [1]
Prevalence and serotypes of Salmonella isolated from chicken and pig samples Out of the 283 chicken carcasses collected in Hebi (n = 141) and Zhoukou (n = 142), 128 Salmonella isolates were recovered with an isolation rate of 45.2%
We found 11 Salmonella isolates that were co-resistant to ciprofloxacin and cefotaxime and all of which were S. enterica serovar Indiana
Summary
Foodborne salmonellosis is an important public health problem worldwide [1]. There is an estimated 94 million annual cases of non-typhoidal Salmonella infections with 155,000 deaths and 85% of these cases are foodborne [2]. Salmonellosis is one of the main causes of morbidity in China, accounting for 75% (30 million cases) of the foodborne diseases [3]. Chickens and pigs are the main reservoirs of human foodborne nontyphoidal Salmonella infections. Fluoroquinolones and extended-spectrum cephalosporins are the most frequently used antimicrobial agents for treating invasive salmonellosis in humans, especially children and the elderly [1,5]. Recent studies have shown that food-producing animals and retail food products might be important reservoirs of fluoroquinolone and/or extended-spectrum cephalosporin-resistant Salmonella which have already been reported in many countries [5,9]. The ciprofloxacin and ceftriaxone co-resistant S. enterica serovar Indiana have been isolated from retail chickens in Beijing and sick animals (ducks and pigs) in Gangdong province, China [10,12]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
