• Journal of Veterinary Clinics
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• v.32 no.2
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• pp.154-157
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• 2015

A major cause of diarrhea in a dog is an infection with bacteria which include Salmonella spp., Campylobacter (C.) spp., and Clostridium (Cl.) spp.. It is fastidious to identify these bacteria by the culture. The purpose of this experiment is to devise the method for detecting Cl. perfringens, C. jejuni, C. coli, and Salmonella spp. with rapid and high sensitivity. The fecal samples collected from 71 normal and 66 diarrheic dog feces were used to compare the prevalence of the enteric pathogens and to develop a multiplex real-time polymerase chain reaction (PCR) assay for clinical use. Detection of Cl. perfringens, C. coli, and C. jejuni in diarrhea feces was higher than normal feces. A developed multiplex real-time PCR is useful for determining the presence and quantity of pathogen-specific or other unique sequences with in a fecal sample.

• Food Science and Biotechnology
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• v.14 no.2
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• pp.216-222
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• 2005

This study was performed to determine the antibiotic susceptibility profiles of Salmonella spp., coliforms, Listeria monocytogenes, Staphylococcus aureus and Vibrio spp. isolated from broiler carcasses, aquacultured flounders, hamburgers, and lettuce, which are foods consumed in large quantities in Korea. Salmonella spp. and L. monocytogenes were isolated only from broiler carcasses and Salmonella spp. had a high multidrug resistance rate of 61.1%. Meanwhile, coliforms and S. aureus were isolated from all four foods tested in this experiment. The multidrug resistance rate of coliforms from broiler carcasses was 50%, and that of Vibrio spp. from flounders was 71.4%. The resistance to tetracycline, streptomycin, ampicillin or carbenicillin was common regardless of the kind of food or isolate.

• Journal of Food Hygiene and Safety
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• v.18 no.4
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• pp.224-228
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• 2003

Random amplified polymorphic DNA (RAPD) analysis is based on the amplification of random DNA segment using a single arbitratrary primer. For typing Salmonella spp., polymorphic DNA patterns identified by this method can be used. To select the primers for RAPD typing Salmonella spp., the performances of 20 primers were compared by analyzing 16 Salmonella spp. reference strains. Reproducible electrophoresis patterns were obtained. Among the 20 primers tested, 4 primers (A, OPG04, OPG10, OPL03) showed better differentiation than the others. At the time discrimination index, band clarity, band number and difficulty of band scoring were considered. These primers will be useful for typing Salmonella spp. in the future. Curretly, we are under investigation for the RAPD typing of contaminated Slmonella spp. for the risk analysis of pork processing plant using the primers.

• Food Science and Preservation
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• v.30 no.2
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• pp.262-271
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• 2023

The objective of this study is to compare and assess the effectiveness of real-time polymerase chain reaction (RT-PCR), loop-mediated isothermal amplification (LAMP), and the selective agar plate method for the detection of Salmonella spp. and Listeria monocytogenes in ready-to-eat (RTE) foods. In RTE foods, the detection performance of the three methods (RT-PCR [SureTect^TM kit and PowerChek^TM kit], LAMP [3M MDS], selective agar) were similar at 0-10, 10-50, 50-100, and 100- CFU/mL of Salmonella spp. and L. monocytogenes. We found that with RT-PCR, the Ct value of salad was significantly higher (p<0.05) than other RTE foods, indicating that fiber plays a critical role as an obstacle to the rapid detection of Salmonella spp. However, the Ct value displayed a mixed pattern according to the inoculation level of L. monocytogenes. The use of rapid detection kits and machines mostly depends on the user's choice, with accuracy, ease of use, and economy being the primary considerations. As an RT-PCR kit, SureTect^TM and PowerChek^TM showed high accuracy in detecting Salmonella spp. and L. monocytogenes in RTE foods, showing that they can replace the existing RT-PCR kits available. Additionally, LAMP also showed excellent detection performance, suggesting that it has the potential to be used as a food safety management tool.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1746-1750
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• 2004

The PBM ${BioSign}^{TM}$ Salmonella (PBMS) test kit based on an mmunochromatographic method was evaluated for the screening of Salmonella spp. in pure cultures, and 80, 15, and 10 artificially and naturally contaminated, and negative controlled food samples, respectively. The PBMS test involves presumptive qualitative procedures, detecting the presence of Salmonella spp. in foods within 26 h total testing period and allowing the user to release negative products 70 h earlier than the conventional methods. The PBMS test using Buffered Peptone Water and Rappaport-Vassiliadis broth was evaluated for 10 different food types for various Salmonella spp. It showed detection limits of 1 to 25 colony forming units (CFU)/25 g. No cross-reaction was observed, particularly to other gramnegative bacteria. These results indicate the PBMS test is a rapid and inexpensive procedure for the screening of Salmonella spp. present at low concentrations (1 to 25 CFU/25 g) in foods.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.50-54
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• 2011

This study's objective was to determine the prevalence of Salmonella spp. in pigs and their farm environments in Korea, and to investigate the relationship between the strains based on their phenotypic and genotypic characteristics. A total of 36 Salmonella spp. were isolated in this study: 18 isolates from 492 pigs (3.7%) and 18 isolates from 418 (4.3%) farmhouse environmental samples from 16 different pig farms. Of the Salmonella strains isolated from the numerous environmental samples, the highest prevalence was observed in slurry or manure, followed by partitions, farmer's hands, floors, water/nipples, ventilation sources, and feed, respectively. All the Salmonella isolates originating from different farms were genetically distinct. In three farms, however, identical phage types and pulse-field gel electrophoresis patterns were observed among Salmonella isolates from pig feces and environmental samples. This study suggests that environments contaminated with Salmonella could pose an infection risk to pigs on pig farms.

• Korean Journal of Veterinary Research
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• v.63 no.2
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• pp.16.1-16.6
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• 2023

Salmonella spp. are pathogens involved in most salmonellosis in rabbits. This study examined Salmonella disease in rabbits raised in Thua Thien Hue, Vietnam. Two hundred and 56 rectal swabs of rabbits were taken, and a carrier rate of 33.98% was found. In addition, all the isolated Salmonella spp. strains were 100% motile; positive for H₂S, catalase, Voges Proskauer, coagulase, citrate, maltose, and dextrose; and negative for indole, methyl red, urease, oxidase, sucrose, and lactose. The Kirby-Bauer method showed that these Salmonella strains were susceptible to doxycycline (93.2%), tetracycline (84.1%), and levofloxacin (65.9%). On the other hand, they were highly resistant to streptomycin (95.5%), ampicillin (93.2%), colistin (40.9%), and gentamicin (34.1%). Furthermore, polymerase chain reaction used to screen for virulence and specific genes of Salmonella strains showed that all Salmonella strains isolated carried InvA, fimA, and Stn.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.123-130
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• 2023

Salmonella spp. are prevalent foodborne pathogens that are infective at relatively low concentrations, thus posing a serious health threat, especially to young children and the elderly. In several countries, the management and regulation of Salmonella spp. in food, including seafood, adhere to a negative detection standard. The risk of infection is particularly high when seafood is consumed raw, which underscores the importance of timely detection of pathogenic microorganisms, such as Salmonella. Accordingly, this study aimed to develop a combined pre-treatment and detection method that includes pre-culture and DNA extraction in order to detect five species of Salmonella at concentrations below 10 CFU/mL in seafood. The effectiveness of the proposed method was assessed in terms of the composition of the enrichment (pre-culture) medium, minimum incubation time, and minimum cell concentration for pathogen detection. Furthermore, a practical DNA extraction method capable of effectively handling high salt conditions was tested and found to be successful. Through polymerase chain reaction, Salmonella spp. Were detected and positively identified in shellfish samples at cell concentrations below 10 CFU/g. Thus, the proposed method, combining sample pre-treatment and cell culture with DNA extraction, was shown to be an effective strategy for detecting low cellular concentrations of harmful bacteria. The proposed methodology is suitable as an economical and practical in situ pre-treatment for effective detection of Salmonella spp. in seafood.

• Korean Journal of Veterinary Research
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• v.56 no.2
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• pp.91-95
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• 2016

This study was conducted to investigate the prevalence and antimicrobial resistance of Salmonella spp. and Escherichia (E.) coli isolated from ducks in Korea. A total of 400 cecal content samples were collected from 40 duck farms in Korea. Isolated Salmonella spp. and E. coli strains were 83 and 364 of the 400 cecal samples, respectively. The most prevalent serotype among the 83 Salmonella isolates was Salmonella Typhimurium (51 isolates: 61.45%). Resistance to the tested antimicrobial agents by Salmonella isolates was low except for erythromycin, while the resistance of the E. coli isolates to the other tested antimicrobial agents was high and 90.9% (331/364) of E. coli isolates showed multi-antimicrobial resistance. Antimicrobial resistance in duck zoonotic pathogens should be of concern to the Korean duck industry, as these pathogens exhibit a high rate of antimicrobial resistance and pose a potential hazard to public health.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.10
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• pp.1522-1527
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• 2010

This study was conducted to find out the minimal time needed for detection of Salmonella spp. which exist at very low concentration in foods by using real-time PCR. The sal-F and sal-R sequences were used as primers and sal-P was used as a probe. The detection limit of Salmonella spp. was $3.77{\times}10^2\;cfu/mL$ in buffered peptone water (BPW). Microbial growth was monitored after artificially inoculated Salmonella spp. into BPW. The obtained growth curve was well fitted with the equation, y＝$0.0127x^2$+0.5927x-0.4317 ($R^2$=0.99), if assuming that 1 cell exists in 25 g sample (0.04 cfu/mL). The microbial concentration will be reduced to 10 fold by adding BPW during sample treatment, so actual initial concentration at the starting point of enrichment is 0.004 cfu/mL. At this condition, real-time PCR detection would be possible only when microbial concentration increase occurs to exceed the detection limit (377 cfu/mL). The time needed for microbial increase was calculated from the growth curve equation as 7 hours and 20 minutes. Therefore the total time required for detection was less than 10 hours including the PCR operating time.