• 한국동물위생학회지
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• 제25권3호
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• pp.275-283
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• 2002

Forty strains of Staphylococcus aureus were isolated from mastitic milk. As a result of antimicrobial susceptibility test, the strains of S aureus revealed 47.5% were resistant to ampicillin and penicillin, and 7.5% to gentamicin. But 45% of isolates were sensitive to antimicrobial agents tested. In case of enterotoxin production, 56.3% of 16 strains produced enterotoxin D. Two strain of enterotoxin D producers produced both enterotoxin B and D. According to isolation date, 15 representative strains were selected. As a results of pulsed field gel eletrophoresis analysis of the 15 representative strains, 14 strains were identical. Therefore we consider the identical strains of S aureus have caused continuously bovine mastitis in this dairy farm. If autogenous vaccine can be made by the strains, it will work well for the prevention of bovine mastitis caused by S aureus.

• Journal of Microbiology and Biotechnology
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• 제27권10호
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• pp.1827-1836
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• 2017

The world dairy industry has long been challenged by bovine mastitis, an inflammatory disease, which causes economic loss due to decreased milk production and quality. Attempts have been made to prevent or treat this disease with multiple approaches, primarily through increased abuse of antibiotics, but effective natural solutions remain elusive. Bee venom (BV) contains a variety of peptides (e.g., melittin) and shows multiple bioactivities, including prevention of inflammation. Thus, in the current study, it was hypothesized that BV can reduce inflammation in bovine mammary epithelial cells (MAC-T). To examine the hypothesis, cells were treated with LPS ($1{\mu}g/ml$) to induce an inflammatory response and the anti-inflammatory effects of BV (2.5 and $5{\mu}g/ml$) were investigated. The cellular mechanisms of BV against LPS-induced inflammation were also investigated. Results showed that BV can attenuate expression of an inflammatory protein, COX2, and pro-inflammatory cytokines such as IL-6 and TNF-${\alpha}$. Activation of NF-${\kappa}B$, an inflammatory transcription factor, was significantly downregulated by BV in cells treated with LPS, through dephosphorylation of ERK1/2. Moreover, pretreatment of cells with BV attenuated LPS-induced production of intracellular reactive oxygen species (e.g., superoxide anion). These results support our hypothesis that BV can decrease LPS-induced inflammatory responses in bovine mammary epithelial cells through inhibition of oxidative stress, NF-${\kappa}B$, ERK1/2, and COX-2 signaling.

• 한국식품위생안전성학회지
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• 제23권3호
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• pp.271-275
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• 2008

콜린은 정상적인 세포벽의 기능, 아세틸콜린의 합성, 지질의 운송, 그리고 매칠기의 공급원으로서 중요한 유기화합물이다. 생물학적인 조직과 식품들 중에 있는 콜린의 분석을 위해 많은 기기분석법들 사용되고 있다. 그러나 이러한 기기분석법들은 고가의 장비를 필요로 하며, 조작이 어렵고, 많은 시간을 필요로 한다. 본 연구에서는 우유 중의 콜린함량을 분석하는데 사용되는 효소측정법을 응용하여 신속하게 소의 혈액과 근육내에 함유된 콜린을 측정할 수 있는 적용기법을 확립하였다. 소의 혈청과 근육에 콜린 표준용액을 spike하여 얻은 표준곡선들은 직선성을 나타내었으며, 0.994 이상의 상관계수를 보였다. 소의 혈청과 근육에서의 회수율은 70.6-85.2%를 보였다. 본 연구를 통하여 확립된 콜린분석법은 생체시료와 식품에 함유된 콜린 함량분석에 용이하게 적용할 수 있을 것으로 기대된다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권12호
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• pp.1830-1836
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• 2003

Studies using natural resistance-associated macrophage protein (NRAMP) identification indicated that cattle could be selected for immunity. Several studies performed on intracellular organisms such as Mycobacterium, Salmonella, Brucella and Leishmania in human and mouse revealed that resistance against these bacteria was dependent on high activity of NRAMP1 in macrophages. However, hardly any researches have been done on Staphylococcus aureus in bovine mastitis, which is an intracellular organism and the main cause of bovine mastitis. The objectives of this study were to establish reverse transcriptase polymerase chain reaction (RT-PCR) methods, through which NRAMP1 mRNA expression could be compared and analyzed between mastitis-resistant and -susceptible cows. NRAMP1 gene and its expression were investigated using 20 cows (Holstein Friesian) in Korea. Cows were evenly split into two groups, with and without histories of clinical mastitis. Equivalent numbers of cows were randomly selected from each group. Monocytes were isolated from the bovine peripheral blood of each selected cows and activated with lipopolysaccharide (LPS). mRNA was separated from the monocytes and cDNA of NRAMP1 was synthesized and amplified using RT-PCR with amplification of $\beta$-actin as a control. The difference in NRAMP1 expressions of mastitis-resistant (n=10) and -susceptible (n=10) Holstein cows was analyzed. Results demonstrate that resistant cows produced more NRAMP1 mRNA than the susceptible ones, and ratios of NRAMP1:$\beta$-actin expression were higher in resistant cows with or without LPS activation. Therefore, this study could be applied to select bovine mastitis resistant cows before infection based on the expression of NRAMP1.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2002년도 국제심포지엄
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• pp.75-75
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• 2002

The present study was conducted for the production of transgenic cloned cows by somatic cell nuclear transfer (SCNT) that secrete human prourokinase into milk. To establish an efficient production system for bovine transgenic SCNT embryos, the offset was examined of various conditions of donor cells including cell type, size, and passage number on the developmental competence of transgenic SCNT embryos. An expression plasmid far human prourokinase (pbeta-ProU) was constructed by inserting a bovine beta-casein promoter, a green fluorescent protein (GFP) marker gene, and a human prourokinase target gene into a pcDNA3 plasmid. Three types of bovine somatic cells including two adult cells (cumulus cells and ear fibroblasts) and fetal fibroblasts were prepared and transfected using a lipid-meidated method. In Experiment 1, developmental competence and rates of GFP expression in bovine transgenic SCNT embryos reconstructed with cumulus cells were significantly higher than those from fetal and ear fibroblasts. In Experiment 2, the effect of cellular senescence in early (2 to 4) and late (8 to 12) passages was investigated. No significant differences in the development of transgenic SCNT embryos were observed. In Experient 3, different sizes of GFP-expressing transfected cumulus cells [large (>30 ${\mu}{\textrm}{m}$) or small cell (<30 ${\mu}{\textrm}{m}$)] were used for SCNT. A significant improvement in embryo development and GFP expression was observed when small cumulus cells were used for SCNT. Taken together, these results demonstrate that (1) adult somatic cells could serve as donor cells in transgenic SCNT embryo production and cumulus cells with small size at early passage were the optimal cell type, and (2) transgenic SCNT embryos derived from adult somatic cells have embryonic development potential.

• 한국동물위생학회지
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• 제30권1호
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• pp.115-123
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• 2007

The therapeutic effect of honeybee venom collected using be venom collector on bovine mastitis was investigated. Mastitic cows from four farms were selected in the Yang-pyeong areas. Chronic mastitic cows were injected with the various concentrations of honey-bee venom per day. There was a significant difference in the reduction rates of somatic cell counts (SCC) according to treatment concentration and method of bee venom. The milk SCC were significantly decreased in all concentrations of bee venom 3 days after treatment. The reduction rates of SCC in treatment of 3, 6, 12 and 24mg honeybee venom were 20, 43, 63.3 and 65.8% respectively. Honeybee venom treatment consisted of two methods, a syringeful and a Bovivet Spenstift. The treatment with Bovivet Spenstift was more effective in the reduction rates of SCC compared with the syringeful. Thirty two out of 53 quarters were cured by Bovivet Spenstift with 12mg bee venom per day for 14 days. The venom cure rates of bovine mastitis by Escherichia coli, Stapylococcus aureus, Gram positive bacteria and Gram negative bacteria were 33.3, 75, 75 and 43.8% respectively. These results suggested that bee venom treatment (by Bovivet Spenstift with 12mg) might be effective for treatment of bovine mastitis.

• 미생물학회지
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• 제49권2호
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• pp.126-130
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• 2013

원유시료에서 분리한 장알균속 세균 245균주의 항생제 내성에 관여하는 다중약물 유출 펌프 유전자 분포도와 항생제 내성 패턴을 연구하였다. 그 결과 245 장알균속 균주의 ampicillin에 대한 내성률은 44.1%, erythromycin에 대한 내성률은 79.2%, tetracycline에 대한 내성률은 76.3%, chloramphenicol에 대한 내성률은 36.3%였으며 vancomycin과 ciprofloxacin에 대해서는 모두 감수성임을 알 수 있었다. 내성 관련 유전자 중 MFS타입의 eme(A)는 82.1%의 장알균에 분포하였으며, ABC 타입의 유전자인 efr(A)는 72.7%, efr(B)는 77.1%, lsa는 71.8%의 장알균에 분포하였다. 특히 이러한 유전자의 기원 세균인 Enterococcus faecalis의 경우 eme(A)는 92.5%, efr(A)는 87.4%, efr(B)는 88.4%, lsa는 88.4%의 분포도를 나타내었다. 한편 동일한 장알균속이지만 종이 다른 장알균에서 eme(A)는 E. faecium 4균주, E. avium 7균주, E. durans 4균주 및 E. raffinosus 2균주에 분포하고 있었다. efr(A)는 E. faecium 2균주와 E. durans 2균주에 분포하였으며, efr(B)는 E. faecium 4균주, E. avium 5균주 및 E. durans 4균주에 분포하였다. 본 연구는 우리나라 원유시료에서 분리한 장알균속의 여러 종의 세균에서 동일한 다중약물 유출 펌프(multidrug efflux pump)의 분포에 대한 첫 번째 보고라 사료되며 E. faecalis 이외의 장알균속에서 이러한 유전자의 분포는 서로 다른 종간의 유전자의 수평적인 이동의 가능성을 시사한다.

• 대한수의학회지
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• 제57권2호
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• pp.117-126
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• 2017

Bovine mastitis is an important microbial disease in the dairy industry. We investigated the frequencies of bacterial pathogens in 62 farms and pathogen antibiotic resistance from mastitis samples (n = 748). We tested the antimicrobial activity of chicken and duck egg white and lysozyme purified from chicken egg white. Moreover, we compared the microbiomes of normal and mastitic raw milk obtained by 16S rRNA gene pyrosequencing and culture methods. The results showed that the frequencies of Gram-positive pathogens (Enterococcus faecalis 37% and Staphylococcus aureus 36%) were higher than that of a Gram-negative pathogen (Escherichia coli 15%). Resistance frequencies to ampicillin and norfloxacin were lowest in Staphylococcus aureus (21%), Enterococcus faecalis (23%), and Escherichia coli (33%), and the antimicrobial activity of chicken egg white was higher than those of lysozyme and duck egg white. Pyrosequencing results revealed clear differences between the microbiomes of mastitic and normal raw milk samples and revealed a slightly similar, but clearly different, composition of pathogens compared to that from the culture method. Thus, pyrosequencing may be useful for elucidating changes in microbiomes during mastitis progression and treatment. A chicken egg white and antibiotic combination may help with mastitis treatment; however, further studies are needed.

• Journal of Dairy Science and Biotechnology
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• 제21권2호
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• pp.97-104
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• 2003

본 연구에서는 우유 앨러지의 원인물질중의 하나인 casein단백질을 생체가 알르겐 물질로 인식할 수 없는 수준의 분자로까지 분해하여 항원성을 저감시키고 또한 풍미가 좋은casein분해물을 제조하기 위하여 분해특성이 다른 효소를 사용하여 만들어진 분해물의 특성과 항원성을 조사하였다. 박테리아 효소인 Neutrase, Alcalase, Protamex, Pescalase을 처리한 casein가수분해물의 평균분자량은 1,100~2,300 dalton이었고 곰팡이 효소인 MP, Flavourzyme, LP, Promod경우에는 거의 770 ~ 1,140 dalton범위였다. 항원성 저감정도를 측정하기 위하여 토끼항casein항혈청을 이용하여 ELISA억제시험을 실시한 결과 항체결합을 50%저해하는 미분해casein단백질의 농도는 $10^{3.6}$ng/ml였다. 박테리아 효소인 Neutrase, Alcalase, Protamex, Pescalase에 의한 Casein가수분해물의 값은 각각 $10^{4.8},\;10^{5.5},\;10^{5.9},\;10^{6.1}\;ng/ml$이었고, 곰팡이 효소인 MP, Flavourzyme, LP, Promod경우에는 각각 $10^{6.3},\;10^{6.3},\;10^{6.5},\;10^{6.8}\;ng/ml$로 나타났다. 박테리아와 곰팡이효소의 조합인 Fla+prota, Pro+prota처리구에서는 $10^{7.4},\;10^{7.3}ng/ml$로 나타났다. 따라서 미분해 casein의 항원성을 1로 하면, casein분해물의 항원성은 최고 1/8,000 이하로 저하되었다. 수신피부아나피랙시스반응(PCA)을 이용한 항원성시험에서 casein으로 피하 감작할 경우 푸른색 반점이 나타났으나 효소처리구에서는 이러한 반점이 나타나지 않아 충분히 항원성이 저감화 되었음을 확인하였다.

• 한국축산식품학회지
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• 제35권1호
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• pp.1-9
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• 2015

In recent years, the knowledge about bifidobacteria has considerably evolved thanks to recent progress in molecular biology. The analysis of the whole genome sequences of 48 taxa of bifidobacteria offers new perspectives for their classification, especially to set up limit between two species. Indeed, several species are presenting a high homology and should be reclassified. On the other hand, some subspecies are presenting a low homology and should therefore be reclassified into different species. In addition, a better knowledge of the genome of bifidobacteria allows a better understanding of the mechanisms involved in complex carbohydrate metabolism. The genome of some species of bifidobacteria from human but also from animal origin demonstrates high presence in genes involved in the metabolism of complex oligosaccharides. Those species should be further tested to confirm their potential to metabolize complex oligosaccharides in vitro and in vivo.