1.Serogroups and antibiogram of Salmonella isolates from dairy cattle in Nkonkobe District, South Africa
Benson Chuck Iweriebor ; Olivia Sochi Egbule ; Aboi Igwaran ; Larry Chikwulu Obi
Malaysian Journal of Microbiology 2021;17(4):452-458
Aims:
The use of antimicrobial agent for treatment or growth promotion has added burden to treat infection diseases
caused by pathogenic bacteria as they can acquire resistance. Salmonella is one of the major zoonotic bacterial
pathogens that acts as a potential reservoir of antimicrobial resistance elements. In this study, the presence of
Salmonella serotypes and the antibiogram patterns of the isolates from fecal samples of healthy cows in some selected
localities in Eastern Cape, South Africa were studied.
Methodology and results:
Two hundred fecal samples were collected from healthy adult cows, of which 180
presumptive Salmonella isolates were recovered by conventional method. The isolates were identified using specific
primer sets that are capable of detecting Salmonella spp. as well as delineating them into serogroups A, B, C1, C2, and
D. Thereafter, antimicrobial susceptibility patterns of the identified isolates were determined by disk diffusion method
against a panel of 12 antibiotics. From the molecular analysis of the isolates, 108 isolates were identified as Salmonella
spp. and the confirmed isolates were further delineated into serogroup and the prevalence of the serogroups detected
were 20%, 18%, 2%, 20% and 40% for serogroup A, B, C1, C2 and D respectively. Extremely high levels of antibiotic
resistances were observed among the study isolates, while serogroup D was the most prevalent serogroup among the
study isolates.
Conclusion, significance and impact of study
In conclusion, dairy cows could be considered as major reservoirs of
antibiotic resistant Salmonella spp. that could be transmitted to humans via the food chain. This poses a significant
public health risk especially to people living around the farms as well as those who consume poorly cooked meat and
those who deal on raw cow meat.
Salmonella Infections, Animal
2.An Epidemic Survey for Salmonellosis Occurred on a Baby's First Birthday Banquet in Jeju Island.
Sang Yeop SHIN ; Jung Yun HONG ; Jong Myon BAE
Korean Journal of Epidemiology 2004;26(1):27-38
OBJECTIVES: A field investigation was done to identify the level of epidemic and to evaluate the infection route of Salmonellosis occurred in a baby's first birthday banquet in Jeju Island. METHODS: Among participants in the banquet given on a baby's first birthday, persons showing gastrointestinal symptoms were conducted by the structured questionnaire and stool culture. The symptomless persons were also surveyed by self-responded structured questionnaire. The causal relationship between food items and gastrointestinal symptoms was proved by odds ratio and Wilcoxon rank-sum test. RESULTS: Salmonella london was identified in the stools of 12 subjects among 20 participants showing gastrointestinal symptoms, as well as in the boiled pork hock. CONCLUSIONS: This outbreak event is thought to happen after participants took the boiled pork hock that contaminated with S almonella london during the storage process.
Humans
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Odds Ratio
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Salmonella
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Salmonella Food Poisoning
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Salmonella Infections*
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Tarsus, Animal
;
Surveys and Questionnaires
3.A modified gentamicin protection assay for detecting invasive phenotype of Salmonella enterica serovar Enteritidis.
Ying WANG ; Wei ZHANG ; Yixuan LI ; Fang JIANG ; Tingting HUANG ; Xin YU ; Hongwei ZHU ; Xingxiao ZHANG
Chinese Journal of Biotechnology 2020;36(11):2459-2466
Salmonella enterica serovar Enteritidis (SE) is one of the most important zoonotic pathogens that cause enteritis and systemic infection in animals and human. Understanding invasive capacities of SE isolates is of vital importance to elucidate pathogenesis of Salmonella infection. To improve the throughput capacity and repeatability of classical gentamicin protection assay (GPA), a modified PGA was developed by taking high-throughput advantage of 96-well cell plates and multichannel pipettes. In addition, drop plate technique rather than spread plate method was applied in the modified GPA protocol for bacterial enumeration. The modified GPA protocol was evaluated by phenotyping intracellular replication of a high virulent and a low virulent SE isolates, JL228 and LN248, in a phagocytic cell line RAW264.7. The protocol was then applied in invasive phenotype determination of 16 SE strains to non-phagocytes (HT-29) and the intracellular replication of 43 SE strains to phagocytes (RAW264.7). Significant lower intra-group and inter-group coefficient of variations of the modified GPA was observed, implying good repeatability and reproducibility over traditional protocol. Further, replication phenotypes were also correlated with those from direct observation by confocal microscopy. Collectively, the improved GPA protocol had advantages of high throughput capacity, good repeatability and reliability, it was also noticed that the protocol also represented a fast and labor-saving alternative scheme for the invasive phenotype determination of Salmonella Enteritidis, and providing reliable phenotype profiles for Salmonella-host interplay interpretation.
Animals
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Gentamicins/pharmacology*
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Humans
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Phenotype
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Reproducibility of Results
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Salmonella Infections, Animal
;
Salmonella enteritidis
4.Competitive exclusion against Salmonella gallinarum of Salmonella enteritidis infected chickens.
Young Ju LEE ; Min Su KANG ; Yong Ku WOO ; In Pil MO ; Ryun Bin TAK
Journal of Veterinary Science 2001;2(1):33-36
To evaluate the degree of competitive exclusion against Salmonella gallinarum(S. gallinarum) of Salmonella enteritidis(S. enteritidis) infected chickens, fifty-six, 4-week old Hyline layer suspected of S. enteritidis infection were challenged with S. gallinarum. All chickens were tested for S. enteritidis isolation using cloacal swabs and serum plate agglutination test using S. enteritidis Ag. before challenge and classified into four groups(SE isolated, SE nonisolated, SE seropositive and SE seronegative). None of the SE isolated and the SE seropositive groups died after challenge and the average weight gains were 245.5g and 254.6g, respectively. But in the SE nonisolated and the SE seronegative groups, mortality was 18.2% and 20.6% and the average weight gains were 150.1g and 111.2g. The incidence of reisolation of S. gallinarum of the SE isolated and the SE seropositive groups were 41.7% and 47.6% from liver, 33.3% and 47.6% from spleen and 8.3% and 14.3% from cecum, respectively, and the SE nonisolated and the SE seronegative group were 63.6% and 64.7% from liver, 84.1% and 88.2% from spleen and 47.7% and 52.9% from cecum. The serological response of the SE isolated and the SE seropositive groups hardly changed from 75.0 and 81.8% before challenge to 75.0 and 85.7% after. But, the other two groups were found to be significantly higher after challenge and increased from 0 and 18.2% to 100%. Consequently, S. enteritidis preinfected chickens were found to be significant different in terms of mortality, weight gain, reisolation of S. gallinarum and serological response compared to noninfected chickens. Moreover, our study shows that S. enteritidis infected chickens appear strong competitive exclusion against the colonization of S. gallinarum.
Animals
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Chickens
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Disease Outbreaks/veterinary
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Korea/epidemiology
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Oviposition
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Poultry Diseases/*microbiology
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Salmonella/*classification/*isolation & purification
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Salmonella Infections, Animal/*microbiology
;
Salmonella enteritidis/*classification/*isolation & purification
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Serotyping
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Weight Gain
5.Characteristics of Non-typhoidal Salmonella Isolates from Human and Broiler-chickens in Southwestern Seoul, Korea.
Hee Jin CHEONG ; Yeon Joo LEE ; In Sook HWANG ; Sae Yoon KEE ; Hye Won CHEONG ; Joon Young SONG ; Jun Man KIM ; Yong Ho PARK ; Ji Hun JUNG ; Woo Joo KIM
Journal of Korean Medical Science 2007;22(5):773-778
Non-typhoidal Salmonella (NTS) is an important commensal microorganism. The purpose of this study was to determine the epidemiological relation between NTS isolates from livestock and NTS isolates from human by analyzing antimicrobial susceptibilities and performing molecular typing. We determined the serotypes of 36 human clinical isolates and 64 livestock isolates, performed antimicrobial susceptibility testing against 8 antibiotics, and determined the molecular types of isolated NTS spp. by pulsed field gel electrophoresis (PFGE). In human isolates, S. enteritidis was the most common serotype (17 isolates; 47.2%) and S. typhimurium the second most (8 isolates; 22.2%). In livestock isolates, S. typhimurium was the most common serotype (15 isolates; 23.44%), and S. enteritidis was the second most (14 isolates; 21.88%). Ampicillin and tetracycline resistance were 50% (32/64 isolates) each among broiler-chicken NTS isolates. No human or livestock NTS isolates showed resistance to ciprofloxacin, TMP-SMX, or ceftriaxone. However, 19.4% (7/36) and 46.8% (30/64) of the human and livestock NTS isolates were resistant to nalidixic acid (MIC > or =16 mg/mL), respectively. The presence of the three identical PFGE molecular types from human and broiler-chicken NTS isolates suggests the possibility of transmission from livestock to humans.
Adult
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Animals
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Chickens
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Cluster Analysis
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Drug Resistance, Bacterial
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Female
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Humans
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Korea
;
Male
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Nalidixic Acid/pharmacology
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Salmonella Infections/epidemiology/metabolism/*microbiology
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Salmonella Infections, Animal/epidemiology/metabolism/*microbiology
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Salmonella enteritidis/metabolism
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Salmonella typhimurium/*metabolism
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Serotyping
6.Biochemical Characteristics and Antimicrobials Susceptibility of Salmonella gallinarum Isolated in Korea.
Young Ju LEE ; Ki Seuk KIM ; Yong Kuk KWON ; Ryun Bin TAK
Journal of Veterinary Science 2003;4(2):161-166
Fowl typhoid (FT) reported since 1992 in Korea is a septicemic disease of domestic birds caused by Salmonella gallinarum (S. gallinarum). The purpose of this study was to investigate the biochemical characteristics and antimicrobials susceptibility of field isolates of S. gallinarum isolated by year in Korea. A total of 258 isolates of S. gallinarum from 1995 to 2001 showed the same pattern in the majority of biochemical test such as IMViC (indole, methyl red, Voges-Proskauer and citrate utilization), carbohydrate fermentation and amino acid decarboxylation, and these results were almost in accordance with the traditional biochemical characteristics of S. gallinarum strain. When the antimicrobial susceptibility test against 258 isolates of S. gallinarum was performed by the disk diffusion method using 12 antimicrobial agents, all isolates from 1995 appeared to be susceptible to all of the antimicrobial agents tested except for tetracycline and oxytetracycline, whereas the vast majority of isolates from 2001 showed the reduced susceptibility to ampicillin (13.0%), gentamicin (43.4%), kanamycin (69.6%), enrofloxacin (6.5%), ciprofloxacin (10.9%), norfloxacin (52.5%) and ofloxacin (82. 6%). The prevalence of the prevalence of completely resisyany isolates resistant isolates to one or more drugs rapidly increased from 0% in 1995 to 93.5% in 2001. The minimal concentrations range of the majority of antimicrobial agents to inhibit 50% (MIC50s) against S. gallinarum isolates increased from 0.06 -- 8 microgram/ml in 1997 to 2 -- 256 microgram/ml in 2001. Especially, MIC50s for gentamicin and fluoroquinolones of isolates from 2001 increased over 10-fold than those of isolates from 1997. Therefore, our results indicate that sorbitol fermentation and arginine decarboxylation showed the diversity by isolates and the vast majority of isolates from 2001 showed the reduced susceptibility to antimicrobials tested.
Animals
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Anti-Bacterial Agents/*pharmacology
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Chickens
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Korea
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*Microbial Sensitivity Tests
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Poultry Diseases/microbiology
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Salmonella/*drug effects/isolation & purification
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Salmonella Infections, Animal/microbiology
7.Simultaneous detection of Lawsonia intracellularis, Brachyspira hyodysenteriae and Salmonella spp. in swine intestinal specimens by multiplex polymerase chain reaction.
Journal of Veterinary Science 2005;6(3):231-237
A multiplex PCR assay was developed for the simultaneous detection of the etiologic agents associated with porcine proliferative enteropathies (PPE), swine dysentery (SD)and porcine salmonellosis (PS)in a single reaction using DNA from swine intestinal samples. Single and multiplex PCR amplification of DNA from Lawsonia intracellularis, Salmonella typhimurium and Brachyspira hyodysenteriae with each primer set produced fragments of the predicted size without any nonspecific amplification, 210-bp, 298-bp and 403-bp bands, respectively. The single PCR assay could detect as little as 100 pg of purified DNA of S. typhimurium and L. intracellularis, and 50 pg of B.hyodysenteriae, respectively. However, multiplex PCR turned out to be 10 times lower sensitivity with S. typhimurium compared with single PCR. With 23 swine intestinal specimens suspected of having PPE, SD and/or PS, the multiplex PCR assay showed identical results with conventional methods except one. In conclusion, this multiplex PCR is a feasible alternative to standard diagnostic methods for detection of L. intracellularis, B. hyodysenteriae and Salmonella spp. from swine intestinal specimens.
Animals
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Desulfovibrionaceae Infections/microbiology/veterinary
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Intestines/microbiology
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Lawsonia Bacteria/*isolation&purification
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Polymerase Chain Reaction/*methods/veterinary
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Salmonella/*isolation&purification
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Salmonella Infections, Animal/diagnosis
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Sensitivity and Specificity
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Spirochaetales/*isolation&purification
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Spirochaetales Infections/microbiology/veterinary
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Swine
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Swine Diseases/*diagnosis/*microbiology
8.The role of rpoS, hmp, and ssrAB in Salmonella enterica Gallinarum and evaluation of a triple-deletion mutant as a live vaccine candidate in Lohmann layer chickens.
Youngjae CHO ; Yoon Mee PARK ; Abhijit Kashinath BARATE ; So Yeon PARK ; Hee Jeong PARK ; Mi Rae LEE ; Quang Lam TRUONG ; Jang Won YOON ; Iel Soo BANG ; Tae Wook HAHN
Journal of Veterinary Science 2015;16(2):187-194
Salmonella enterica Gallinarum (SG) causes fowl typhoid (FT), a septicemic disease in avian species. We constructed deletion mutants lacking the stress sigma factor RpoS, the nitric oxide (NO)-detoxifying flavohemoglobin Hmp, and the SsrA/SsrB regulator to confirm the functions of these factors in SG. All gene products were fully functional in wild-type (WT) SG whereas mutants harboring single mutations or a combination of rpoS, hmp, and ssrAB mutations showed hypersusceptibility to H2O2, loss of NO metabolism, and absence of Salmonella pathogenicity island (SPI)-2 expression, respectively. A triple-deletion mutant, SGDelta3 (SGDeltarpoSDeltahmpDeltassrAB), was evaluated for attenuated virulence and protection efficacy in two-week-old Lohmann layer chickens. The SGDelta3 mutant did not cause any mortality after inoculation with either 1 x 10(6) or 1 x 10(8) colony-forming units (CFUs) of bacteria. Significantly lower numbers of salmonellae were recovered from the liver and spleen of chickens inoculated with the SGDelta3 mutant compared to chickens inoculated with WT SG. Vaccination with the SGDelta3 mutant conferred complete protection against challenge with virulent SG on the chickens comparable to the group vaccinated with a conventional vaccine strain, SG9R. Overall, these results indicate that SGDelta3 could be a promising candidate for a live Salmonella vaccine against FT.
Administration, Oral
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Animals
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Bacterial Proteins/*genetics/immunology
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*Chickens
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Female
;
Poultry Diseases/*immunology/microbiology
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Salmonella Infections, Animal/*immunology/microbiology
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Salmonella Vaccines/administration & dosage/genetics/*immunology
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Salmonella enterica/immunology/*physiology
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Vaccines, Attenuated/administration & dosage/genetics/immunology
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Virulence
9.Dissemination and tracking of Salmonella spp. in integrated broiler operation.
Aeran KIM ; Young Ju LEE ; Min Su KANG ; Sang Ick KWAG ; Jae Keun CHO
Journal of Veterinary Science 2007;8(2):155-161
Controlling Salmonella in integrated broiler operation is complicated because there are numerous potential sources of Salmonella contamination, including chicks, feed, rodents, wild poultry operations, and the processing plant. The objective of this study was to investigate the distribution of Salmonella through all phases of two integrated broiler operations and to determine the key areas related to the control of all known sources of infection. Two different Salmonella serotypes were observed at integrated broiler chicken company A. S. enteritidis, the predominant company A isolate, was consistently found in the breeder farm, hatcheries, broiler farms, and chicken slaughterhouse. At company B, a total of six different serotypes, S. heidelberg, S. senftenberg, S. enteritidis, S. blockley, S. gallinarum, and S. virchow, were detected. Although S. heidelberg was not found in the broiler farms, it was consistently found in the breeder farm, hatcheries, and chicken slaughterhouse. In addition, S. enteritidis was found in the hatcheries, broiler farm, and chicken slaughterhouse. In order to obtain the genetic clonality, 22 S. enteritidis isolates were digested with XbaI and analyzed by pulsed-field gel electrohporesis (PFGE). A difference in the PFGE pattern was found to be related to the origin of the integrated broiler operation. These data support the critical need to control Salmonella in breeder farms and hatcheries, and demonstrate important points related to the control of infection in large-scale poultry operations of Korea.
Animal Husbandry
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Animals
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*Chickens
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DNA, Bacterial/chemistry/genetics
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Electrophoresis, Gel, Pulsed-Field/veterinary
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Female
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Food Microbiology
;
Korea/epidemiology
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Poultry Diseases/epidemiology/*microbiology/transmission
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Salmonella/classification/genetics/*isolation & purification
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Salmonella Infections, Animal/epidemiology/*microbiology/transmission
10.Prevalence of Lawsonia intracellularis, Brachyspira hyodysenteriae and Salmonella in swine herds.
Journal of Veterinary Science 2005;6(4):289-293
The prevalence of Lawsonia intracellularis, Brachyspira hyodysenteriae and Salmonella spp. were investigated by multiplex PCR using fecal samples of pigs with diarrhea or a history of diarrhea. The overall herd prevalence of L. intracellularis, B. hyodysenteriae and Salmonella spp. were 46.5%, 37.2% and 51.1%, respectively. Also, the prevalence of L. intracellularis, B. hyodysenteriae and Salmonella spp. among all sampled pigs were 19.9%, 10.8% and 17.7%, respectively. Seventeen of 43 herds were positive with 2 enteric organisms, and 2 herds were positive with L. intracellularis, B. hyodysenteriae and Salmonella spp. simultaneously. It was notable that 11 of 12 herds with more than 2, 000 pigs were affected with Salmonella spp., and that only 2 of 12 the herds were affected with B. hyodysenteriae. This study suggested that herds positive for L. intracellularis, B. hyodysenteriae and Salmonella spp. were distributed throughout Korea, although the relationship among other pathogens such as viral or parasitic ones and/or with metabolic disorders was not determined.
Animals
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DNA, Bacterial/isolation&purification
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Desulfovibrionaceae Infections/epidemiology/microbiology/*veterinary
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Diarrhea/microbiology/veterinary
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Korea/epidemiology
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*Lawsonia Bacteria/isolation&purification
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Polymerase Chain Reaction/veterinary
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Prevalence
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*Salmonella/isolation&purification
;
Salmonella Infections, Animal/*epidemiology/microbiology
;
*Serpulina hyodysenteriae/isolation&purification
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Spirochaetales Infections/epidemiology/microbiology/*veterinary
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Swine
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Swine Diseases/*epidemiology/microbiology