• Korean Journal of Veterinary Service
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• v.32 no.2
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• pp.139-146
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• 2009

Bovine brucellosis is a zoonosis, long incubation period and chronic infectious disease, usually caused by Brucella abortus. This study was carried out to investigate the biotyping and biochemical characterization of B. abortus isolated from 208 farm 871 korean cattle and holstein diagnosed brucellosis by serological positive in Gyeongbuk province during the period from 2002 to 2006. B. abortus was isolated from 124 (14.2%) of 871 cattle, and isolated 110 (13.4%) of 820 Korean cattle and 14 (27.5%) of 51 holstein in breed. The uterus of korean cattle was isolated in 8 (17.8%) of 45 cattle and supramammary lymph none of holstein was isolated 11 (68.8%) of 16 cattle. 101 (12.5%) of 810 serological positive blood samples were isolated B. abortus. The isolation rate of B. abortus was correlated with antibody titers. The biochemical characterization of isolates was non-hemolytic, production of H$_2$S, oxidase-positive, catalase-positive, hydrolyzation of urea and growth of basic fuchsin dye medium. As a result, all of isolates was identified B. abortus bv 1. 124 isolates were susceptible to ampicillin, lincospectin, amikacin, gentamicin, kanamycin, neomycin, streptomycin, tetracycline, ciprofloxacin, norfloxacin and enrofloxacin.

• Korean Journal of Veterinary Service
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• v.30 no.2
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• pp.251-258
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• 2007

Bovine brucellosis has occurred for years in Gyeonggi province under the national test and slaughter scheme. The serum agglutination test (SAT) is a diagnostic tool to confirm the disease despite the argument on its specificity. We selected 8 farms where only one or two individuals were diagnosed as brucellosis through SAT at the primary regular herd check and isolated the causative organism and characterized the species by species-specific PCR. The pathogen isolation was successful in 6 farms out of 8 farms by microbiological culture, showing the successful rate of 75%. The isolation rate of the causative organism represents 70% from supra-mammary lymph node and 60% from uterine tissues. They were characterized as Brucella abortus biovar 1 after biotyping by PCR, showing the fragment of 498 bp. Five of 8 farms were diagnosed as brucellosis two to four times more over the intervals of two or three months. Here in this study we briefly showed the correlation of the sporadic outbreak of brucellosis tested by SAT and the isolation of the causative organism. Moreover one or two reactors against brucellosis among considerable size of herd may indicate that SAT failed to detect potentially infected individuals in the incubation stage or chronic phase of the disease.

• Korean Journal of Veterinary Research
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• v.39 no.6
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• pp.1106-1111
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• 1999

In a kenel of 62 dogs, 33 were diagnosed as infected dogs Brucella canis by serological test and blood cultures in a large kennel in Chonnam area. Twenty eight of 33 dogs were treated with combined antibiotics therapy consisting of tetracycline and dihydrostregtomycin. After the first treatment, all dogs became abacteremic and serologic titers declined. Abortion due to B canis infection could be prevented by antibiotic therapy during pregnancy. However, sequential antibiotics therapy for 4 weeks did not eradicate B canis from affected bitch. According to results of serological and blood culture tests, effect of antibiotics treatment respectively revealed that 17 of the originally infected dogs were cure with second therapy schedule at 2 months and 27 of that with 6 months after second therapy.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.190-196
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• 2016

In this study, the Brucella abortus ohr gene coding for an organic hydroperoxide resistance protein (Ohr) was cloned into a maltose fusion protein expression system (pMAL), inserted into Escherichia coli, and purified, and its immunogenicity was evaluated by western blot analysis using Brucella-positive mouse sera. The purified recombinant Ohr (rOhr) was treated with adjuvant and injected intraperitoneally into BALB/c mice. A protective immune response analysis revealed that rOhr induced a significant increase in both the IgG1 and IgG2a titers, and IgG2a reached a higher level than IgG1 after the second and third immunizations. Additionally, immunization with rOhr induced high production of IFN-γ as well as proinflammatory cytokines such as TNF, MCP-1, IL-12p70, and IL-6, but a lesser amount of IL-10, suggesting that rOhr predominantly elicited a cell-mediated immune response. In addition, immunization with rOhr caused a significantly higher degree of protection against a virulent B. abortus infection compared with a positive control group consisting of mice immunized with maltose-binding protein. These findings showed that B. abortus rOhr was able to induce both humoral and cell-mediated immunity in mice, which suggested that this recombinant protein could be a potential vaccine candidate for animal brucellosis.

• Journal of Environmental Health Sciences
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• v.37 no.6
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• pp.482-487
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• 2011

Salmonellosis and brucellosis have caused a considerable danger of farmed animals and economic loss in animal farming industry. In this study, the disinfection efficacy of Citra-Kill$^{(R)}$, a commercial disinfectant, composed to quaternary ammonium chloride and citric acid was evaluated against S. typhimurium and Brucella ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at $4^{\circ}C$. Citra-Kill$^{(R)}$ and test bacteria were diluted with distilled water (DW), hard water (HW) or organic matter suspension (OM) according to treatment condition. On OM condition, the bactericidal activity of Citra-Kill$^{(R)}$ against S. typhimurium and Brucella ovis was lowered compared to that on HW condition. As Citra-Kill$^{(R)}$ possesses bactericidal efficacy against animal pathogenic bacteria such as S. typhimurium and Brucella ovis, this disinfectant solution can be used to control the spread of animal bacterial diseases.

• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.328-335
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• 1998

Outer membrane proteins(OMPs) of Brucella abortus 1119-3 strain were extracted by Triton X-100 treatment, and fractionated by DEAE-cellulose column chromatography and Sephacryl S-300 column chromatography. The antigenic proteins in these fractions were identified by Western blot analysis. In Western blot analysis, a single band(38kDa) was observed in the DEAE fractions from 36th fraction to 38th fraction against sera of cattle infected with B abortus. And other fractions have several bands. However, the Sephacryl S-300 fractions exhibited a total of 3 peaks of proteins with a broad range from about 30 to 116kDa. In order to characterize further, the extracted OMPs and the DEAE fractions were analyzed by two dimensional polyacrylamide gel electrophoresis(2-DE) and Western blot using serum from naturally infected cattle with Brucella spp. The 2-DE immunoblots of DEAE fraction showed immunoreactive spots more than twenty two. The major protein spots have ranging from about 32 to 47kDa. The pI values of the spots were detected from pH 4.7 to 5.4. Among the major protein spots, the 38kDa protein which is a specific antigen, located at the point of approximately a pI 4.8.

• Parasites, Hosts and Diseases
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• v.36 no.4
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• pp.281-284
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• 1998

Humoral immune response of young chicks to Brucella abortus strain 1119-3 inoculation was monitored to verify the degree of immunosuppression caused by infection with Cryptosporidium baileyi. Young chicks (2-day-old) were orally inoculated each with $2{\times}10^6$ oocysts of C. baileyi, and then injected intramuscularly with 0.3 $m\ell$ B. abortus strain 1119-3 containing $1{\times}10^9$ living organisms on day 14 postinoculation (PI). Serum samples were tested by plate agglutination test on day 17 PI onwards at an interval of 3-6 days over a period of 36 days. Infected chicks with the coccidium showed significantly lower antibody titers than those of uninfected controls (P<0.05). These findings document that C. baileyi infection in early life stage may predispose chicks easily to other potential poultry diseases.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1723-1729
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• 2018

The aim of this work is to investigate the protective efficacy of emodin, an active, naturally-occurring anthraquinone derivative of several traditional Chinese herbs, against Brucella abortus infection in macrophages. Brucella were incubated with different concentrations of emodin and showed that bacterial survival rates were markedly reduced in a dose-dependent manner at increasing incubation time points. Through bacterial infection assay, the highest non-cytotoxic concentration of emodin demonstrated attenuated invasion of Brucella into macrophages, however it did not inhibit the growth of these pathogens within the host cells. On the other hand, emodin effectively decreased the number of bacteria that adhered to host cells, which indicated its potential as an anti-adhesin agent. Furthermore, using immunoblotting and FACS assay for detecting MAPK signaling proteins and F-actin polymerization, respectively, the results showed that the emodin-incubated cells displayed modest reduction in the phosphorylation levels of ERK1/2 and inhibition of F-actin polymerization as compared to control cells. These findings indicate the potential use of emodin as a naturally-occurring alternative method for the prevention of animal brucellosis although this requires confirmation of safe clinical doses.

• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.642-648
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• 2020

In this study, we investigated the effects of linoleic acid (LA) treatment on Brucella abortus infection in professional phagocyte RAW264.7 cells, particularly during the pathogen's invasion and intracellular growth in these cells, as well as in murine model BALB/c mice focusing on bacterial splenic proliferation and immunoregulatory activities. LA inhibited the growth of Brucella in a dose- and time-dependent manner. The ability of the pathogen to enter the phagocytes was inhibited as was its survival within these cells. This was accompanied by increased nitrite accumulation in these cells at 24 h post-infection. The concentration of LA used in the present study did not affect the total body weight or liver function of the mice. During Brucella infection, the total splenic weight of these animals was not changed; rather, resistance to bacterial proliferation was enhanced in the spleen. Furthermore, mice treated with LA displayed elevated levels of IL-12 and IFN-γ but reduced levels of IL-10 during infection. The findings in this study showed the regulatory role of LA against B. abortus infection suggesting its potential use in designing intervention strategy for brucellosis.

• Korean Journal of Veterinary Service
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• v.21 no.4
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• pp.451-465
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• 1998

The present study was carried out to investigate the prevalence of brucellosis in Kyungbuk area for the 3 years from 1966 to 1998. Collective milk samples were routinely screened to detect positive farms by using the milk ring test(MRT), and serum agglutination test was performed to detect sero-positive individuals in the MRT positive farms. Attempt were made to isolate the causative organismas from slaughtered sero-positive reactors and some biochemical and polymerase chain reation characters of the isolates were also made to identify the organisms. Seroprevalence to brucellosis in peoples who are close contact with infected dairy herds was also investigated. Brucellosis of dairy cattle was rare before 1997, but has been broken more frequently since early 1998. By the MRT for dairy herds, positive rate was gradually increased every year : 0.6% in 1996, 1.5% in 1997, 3.9% in 1998. Among 262 MRT-positive herds, only 21 herds(8.0%) showed positive brucellosis in serological test. The isolation rates of Brucella sp from tested materials were 51.2% in supramammary glands, 39.5% in milks, and 50.0% in pulmonary Iymphnode, respectively. Isolated strain and biotype were Brucella(B) arbortus biotype 1 in 26 heads, and were B suis biotype 1 in 2 heads. Isolated strain and vaccine strain were very similar in their colony morphology and staining. In drug susceptibility, isolated stains(B abortus) and vaccine strain(B abortus RB-51) were sensitive to ampicillin, gentamycin, kanamycin, neomycin, penicillin, streptomycin, and to tetracycline, but resistant to erythromycin. In the PCR, field strains reacted to BA and IS711 primers, and vaccine strain reacted to BA, IS711, and RB5l primers. In the plate agglutination test of 96 sera of human contacted with animals, serum antibody titer detected 1 : 100 in one person, 1 : 200 in one, and below 1 : 25 in the others.