• Korean Journal of Veterinary Research
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• v.50 no.1
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• pp.59-62
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• 2010

A 2-year-old lineolated parakeet (Bolborhynchus lineola) was presented with abdominal distention and respiratory distress for two months. The bird was poorly fleshed and the liver was enlarged on coelomic palpation. Plain and contrast radiographic examinations exhibited hepatomegaly and distended intestinal loop, which compromised the air sacs. Multifocal hyperechogenecity was observed in the liver on ultrasonography. Postmortem gross examination revealed hepatomegaly with numerous pinpoint tan foci in the hepatic parenchyma and distended small intestine filled with adult ascarids. Microscopically, granulomatous hepatitis and enteritis infected by intrahistiocytic acid-fast bacilli were evident. Polymerase chain reaction indicated that the acid-fast bacilli were Mycobacterium avium subsp. avium.

• Korean Journal of Veterinary Research
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• v.54 no.1
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• pp.55-57
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• 2014

Paratuberculosis caused by Mycobacterium avium subsp. paratuberculosis (MAP) has extended latent periods of infection. Due to this property, difficulties in the detection of fecal shedder have been raised. A newly designed method for DNA extraction from fecal specimens, mGITC/SC was evaluated in terms of diagnostic efficiency. The detection limit of IS900 real-time PCR was about 50 MAP (1.5 cfu) in 250 mg of feces (6 cfu per g). Also, this DNA extraction method was faster and cheaper than that using commercial kit or other methods. Consequently, the mGITC/SC is an economical DNA extraction method that could be a useful tool for detecting MAP from fecal specimens.

• Journal of Veterinary Clinics
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• v.32 no.3
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• pp.219-223
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• 2015

Mycobacterium avium subsp. paratuberculosis (MAP) causes paratuberculosis or Johne's disease, an intestinal granulomatous infection in domestic and wild animals. The study aimed to develop and evaluate a panel of multiplex quantitative real-time polymerase chain reaction (mqPCR) assay for simultaneous detection of three MAP-specific genes (IS900, F57 and ISMAP02 genes). The analytic sensitivity (i.e., limit of detection, expressed as cells per 1 ml) was 150 for IS900, 1500 for F57, and 50 for ISMAP02. The specificity of the method was determined by testing 152 bovine fecal samples. Based on the test, it showed that the assay simultaneously detected the target genes in short period of time and at lower cost compared to laboratory routine tests. The test agreement between the assay and routine test was 94%. The discrepancy in the results was due to samples that were tested positive by the panel but negative by the routine tests, suggesting that the assay has higher sensitivity than the routine tests. In conclusion, the mqPCR assay could be a rapid and accurate testing tool for investigating paratuberculosis or Johne's disease cases in domestic and wild animals.

• Food Science of Animal Resources
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• v.31 no.2
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• pp.147-157
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• 2011

Mycobacterium avium paratuberculosis (MAP), the cause of Johne's disease in animals, may be a causative agent of Crohn's disease (CD) in humans, but the evidence supporting this claim is controversial. Milk, meat, and water could be potential sources of MAP transmission to humans. Thus, if the link between MAP and Crohn's disease is substantiated, the fact that MAP has been detected in retail foods could be a public health concern. The purpose of the present study was to review the link between MAP and CD, the prevalence of MAP in foods, heat inactivation, control of MAP during food processing, and detection methods for MAP. Although MAP positive rates in retail milk in nine countries ranged from 0 to 2.9% by the culture method and from 4.5 to 15.5% by PCR, high temperature short time pasteurization can effectively control MAP. The effectiveness of pasteurization to inactivate MAP depends on the initial concentration of the MAP in raw milk. Development of highly sensitive and specific rapid detection methods for MAP may enhance investigation into the relationship between MAP and CD, the prevention of the spread of MAP, and problem-solving related to food safety. Collaboration and efforts by government agencies, the dairy industry, farmers, veterinarians, and scientists will be required to reduce and prevent MAP in food.

• Journal of Microbiology and Biotechnology
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• v.25 no.2
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• pp.255-267
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• 2015

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne's disease, a chronic debilitating disease affecting ruminants worldwide. In the present study, we aimed to determine the major gene networks and pathways underlying the immune response to MAP infection using whole-blood cells, as well as provide the potential transcriptional markers for identifying the status of MAP infection. We analyzed the transcriptional profiles of whole-blood cells of cattle identified and grouped according to the presence of MAP-specific antibodies and the MAP shed by them. The grouping was based on the results obtained by ELISA and PCR analyses as follows: i) Test1 group: MAP-negative results obtained by ELISA and positive results obtained by PCR; ii) Test2 group: MAP-positive results obtained by ELISA and negative results obtained by PCR; iii) Test3 group: MAP-positive results obtained by ELISA and positive results obtained by PCR; iv) uninfected control: MAP-negative results obtained both by ELISA and PCR analysis. The results showed down-regulated production and metabolism of reactive oxygen species in the Test1 group, activation of pathways related to the host-defense response against MAP (LXR/RXR activation and complement system) in the Test2 and Test3 groups, and anti-inflammatory response (activation of IL-10 signaling pathway) only in the Test3 group. Our data indicate a balanced response that serves the immune-limiting mechanism while the host-defense responses are progressing.

• Korean Journal of Veterinary Research
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• v.55 no.2
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• pp.89-95
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• 2015

Johne's disease, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is one of the most widespread and economically important diseases in cattle. Current diagnostic methods are based on the detection of anti-MAP antibodies in serum or isolation of the causative agent. However, these techniques are often not applicable for cases of subclinical infection due to relatively low sensitivity. Therefore, finding new antigen candidates that strongly react with the host immune system had been attempted. To effectively detect infection during the subclinical stage, several antigen candidates were selected based on previous researches. Characteristics of the selected antigen candidates were analyzed using bioinformatics-based prediction tools. A total of nine antigens were selected (MAP0862, MAP3817c, MAP2077c, MAP0860c, MAP3954, MAP3155c, MAP1204, MAP1087, and MAP2963c) that have MAP-specific and/or high immune responses to infected animals. Using a transmembrane prediction tool, five of the nine antigen candidates were predicted to be membrane protein (MAP3817c, MAP3954, MAP3155c, MAP1087, and MAP1204). Some of the predicted protein structures identified using the I-TASSER server shared similarities with known proteins found in the Protein Data Bank database (MAP0862, MAP1204, and MAP2077c). In future studies, the characteristics and diagnostic efficiency of the selected antigen candidates will be evaluated.

• BMB Reports
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• v.47 no.2
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• pp.115-120
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• 2014

In this study, we show that Mycobacterium avium subsp. paratuberculosis MAP1305 induces the maturation of bone marrow-derived dendritic cells (BMDCs), a representative antigen presenting cell (APC). MAP1305 protein induces DC maturation and the production of pro-inflammatory cytokines (Interleukin (IL)-6), tumor necrosis factor (TNF)-${\alpha}$, and IL-$1{\beta}$) through Toll like receptor-4 (TLR-4) signaling by directly binding with TLR4. MAP1305 activates the phosphorylation of MAPKs, such as ERK, p38MAPK, and JNK, which is essential for DC maturation. Furthermore, MAP1305-treated DCs transform naive T cells to polarized $CD4^+$ and $CD8^+$ T cells, thus indicating a key role for this protein in the Th1 polarization of the resulting immune response. Taken together, M. avium subsp. paratuberculosis MAP1305 is important for the regulation of innate immune response through DC-mediated proliferation of $CD4^+$ and $CD8^+$ T cells.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.535-542
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• 2001

A multiplex PCR technique was developed for detecting specifically each Mycobacterium bovis, M. tuberculosis, M. avium and M. avium subsp, paratuberculosis, respectively, using clinical samples of field cattle. To apply this novel technique to clinical specimens, blood sample was obtained from live cows comprising 11 intradermal tuberculin test (ITT)-positive and 17 ITT-negative and tested by multiplex PCR. Positive results were obtained from 15 cows by the multiplex PCR, showing that 4 (23.5%) of the 17 ITT-negative cows were multiplex PCR positive. The multiplex PCR results also showed that among the 15 positive cows, 7 (46.7%) were infected with M. bovis, 1 (6.7%) with M. tuberculosis and 7 (46.7%) with M. avium. The sensitivity and specificity of multiplex PCR in comparison with those of ITT were 100% and 76.5%. The correlation between the multiplex PCR and ITT assays with blood samples was considered excellent, 85.7% agreement and ${\kappa}=0.72$. The results obtained, using reference mycobacterial strains and typed clinical samples, show that the multiplex PCR method may be a rapid, sensitive, and specific tool for the differential identification of various mycobacterial strains in a single-step assay. Therefore, multiplex PCR assay is a useful tool for early diagnosis of tuberculosis in live cattle and to identify the species or complex of mycobacterium from clinical samples.

• Journal of Veterinary Clinics
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• v.35 no.1
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• pp.7-9
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• 2018

Mycobacterium avium subspecies paratuberculosis (MAP) causes a significant economic burden in the animal production industry. The purpose of this study was to investigate the prevalence of MAP in the feces of wild duck populations residing along a riverside close to farms in the center of Korea. From wild Spot-billed (Anas poecilorhyncha) and Mallard (Anas platyrhynchos) ducks, 128 fecal samples were collected and analyzed using multiplex real-time PCR, sequencing, and nested PCR to confirm the presence of the organism. The molecular analyses showed that 44 samples (34.4%) were positive for MAP, suggesting a high prevalence of MAP in the wild duck population. Considering the nature and habitat of wild ducks, this result suggests that the organism was introduced from contaminated water from waste of nearby farms, and that the wild ducks may act as a transmitter of the organism to other wild birds or livestock.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1167-1175
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• 2013

Paratuberculosis (PTB) or Johne's disease is one of the most serious chronic debilitating diseases of ruminants worldwide that is caused by Mycobacterium avium subsp. paratuberculosis (MAP). MAP is a slow-growing bacterium that has very long latent periods, resulting in difficulties in diagnosing and controlling the disease, especially regarding the diagnosis of fecal shedders of MAP without any clinical signs. Based on this situation, attempts were made to identify biomarkers that show early responses to MAP infection in a macrophage cell line, RAW 264.7. In response to the infection with the bacterium, a lot of genes were turned on and/or off in the cells. Of the altered genes, three different categories were identified based on the time-dependent gene expression patterns. Those genes were considered as possible candidates for biomarkers of MAP infection after confirmation by quantitative RT-PCR analysis. To the best of our knowledge, this is the first attempt at discovering the host transcriptomic biomarkers of PTB, although further investigation will be required to determine whether these biomarker candidates are associated within the natural host.