Prevalence, Virulence Genes and Antimicrobial Resistance Profiles of Salmonella Serovars from Retail Beef in Selangor, Malaysia

Abstract

The aim of the present study was to investigate the prevalence of Salmonella spp., Salmonella Enteritidis and Salmonella Typhimurium in retail beef from different retail markets of Selangor area, as well as, to assess their pathogenic potential and antimicrobial resistance. A total of 240 retail beef meat samples (chuck = 60; rib = 60; round = 60; sirloin = 60) were randomly collected. The multiplex polymerase chain reaction (mPCR) in combination with the most probable number (MPN) method was employed to detect Salmonella spp., S. Enteritidis and S. Typhimurium in the meat samples. The prevalence of Salmonella spp., S. Enteritidis and S. Typhimurium in 240 beef meat samples were 7.50, 1.25, and 0.83%, respectively. The microbial loads of total Salmonella was found in the range of <3 to 15 MPN/g. Eight different serovars of Salmonella were identified among the 23 isolates, and S. Agona was the predominant serovar (26.09%). Interestingly, all the Salmonella isolates were resistant to penicillin, erythromycin and vancomycin, but the sensitivity was observed for tetracycline, gentamicin and amoxicillin/clavulanic acid. All 23 isolates were resistant to at least three antibiotics. Two S. Typhimurium isolates (8.70%) exhibited the highest multiple antibiotic resistance (MAR) index value of 0.56 which shown resistance to nine antibiotics. PCR analysis of virulence genes showed that all Salmonella isolates (100%) were positive for the invA gene. Meanwhile, pefA was only identified in S. Enteritidis and S. Typhimurium. The findings in this study indicate that retail beef products tested were widely contaminated with multi-drug resistant (MDR) Salmonella and various virulence genes are present among the isolated Salmonella serovars.

Confirmation of Antimicrobial Resistance by Using Resistance Genes of Isolated Salmonella spp. in Chicken Houses of North West, South Africa.

“…MDR Salmonella has been observed in other countries such as Malaysia (Thung et al, 2018). MDR Salmonella isolates are considered to be highly virulent than non-MDR (Thung et al, 2018) and this finding was a major concern in the current study.…”

“…This is worrying because some antibiotics are recommended drugs for the treatment of salmonellosis (Hirose et al, 2001). MDR Salmonella has been observed in other countries such as Malaysia (Thung et al, 2018). MDR Salmonella isolates are considered to be highly virulent than non-MDR (Thung et al, 2018) and this finding was a major concern in the current study.…”

“…Recent studies have demonstrated that Salmonella serotypes such as S. heidelberg, S. typhimurium, S. infantis, S. uganda, S. newport, S. typhi, S. paratyphi, S. agona and S. hadar exhibit antibiotic resistance (Mathole et al, 2017;Zhao et al, 2017;Odoch et al, 2018;Thung et al, 2018). Furthermore, the increasing frequency of resistance of Salmonella spp.…”

“…Furthermore, the increasing frequency of resistance of Salmonella spp. to antibiotics such as chloramphenicol, tetracycline, and ampicillin has been reported in many countries (Olobatoke and Mulugeta, 2015;Odoch et al, 2018;Thung et al, 2018). Antimicrobial resistance, especially in Salmonella serovars, has also been implicated to play a role in their virulence (Mathole et al, 2017).…”

Alternate antimicrobial resistance genes in multidrug resistant Salmonella spp. isolated from retail meats in Vietnam using RNA‐sequencing analysis

“…Along with issues concerning antibiotic resistance in clinical settings, there has been increased interest in antimicrobial resistance genes (ARGs) in food. ARGs have been detected in retail meat and seafood sources (Thung et al, 2017), foods other than meat (Maka, Mackiw, Sciezynska, & Popowska, 2015), as well as poultry and swine (Chuanchuen & Padungtod, 2009). This study indicated the diversity and abundance of ARGs in food sources.…”