• Asian-Australasian Journal of Animal Sciences
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• 제30권11호
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• pp.1590-1597
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• 2017

Objective: This study aims to identify the relationship between odd- and branched-chain fatty acids (OBCFAs) and microbial nucleic acid bases in the rumen, and to establish a model to accurately predict microbial protein flow by using OBCFA. Methods: To develop the regression equations, data on the rumen contents of individual cows were obtained from 2 feeding experiments. In the first experiment, 3 rumen-fistulated dry dairy cows arranged in a $3{\times}3$ Latin square were fed diets of differing forage to concentration ratios (F:C). The second experiment consisted of 9 lactating Holstein dairy cows of similar body weights at the same stage of pregnancy. For each lactation stage, 3 cows with similar milk production were selected. The rumen contents were sampled at 4 time points of every two hours after morning feeding 6 h, and then to analyse the concentrations of OBCFA and microbial nucleic acid bases in the rumen samples. Results: The ruminal bacteria nucleic acid bases were significantly influenced by feeding diets of differing forge to concentration ratios and lactation stages of dairy cows (p<0.05). The concentrations of OBCFAs, especially odd-chain fatty acids and C15:0 isomers, strongly correlated with the microbial nucleic acid bases in the rumen (p<0.05). The equations of ruminal microbial nucleic acid bases established by ruminal OBCFAs contents showed a good predictive capacity, as indicated by reasonably low standard errors and high R-squared values. Conclusion: This finding suggests that the rumen OBCFA composition could be used as an internal marker of rumen microbial matter.

• 생명과학회지
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• 제10권1호
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• pp.22-36
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• 2000

The mammary gland contains a subpopulation of epithelial cells with large proliferative potentials which are the likely targets for carcinogens. These clonogenic cells can proliferate and differentiate into functional glandular structures. Multicellular secretory alveolar units (AU) develop from these clonogens in grafts of monodispersed rat mammary epithelial cells (RMEC) in gland-free mammary fat pads in intact recipient F344 rats co-grafted with mammotropic hormone-secreting pituitary tumors (MtT F4). Multicellular nonsecretory ductal units (DU) develop in grafts of monodispersed RMEC in gland-free fat pads in adrenalectomized recipient WF rats co-grafted with MtT W10. However, this effect were reversed by hydrocortisone replacement therapy. RMEC were isolated from appropriate donor rats as monodispersed mixed cells or, alternatively, RNA＋ cells were sorted by flow cytometry of mixed RMEC stained with FITC-RNA and PE-anti-Thy-1.1 monoclonal antibody. We grafted mixed or sorted PNA+ cells in gland-free mammary fat pads in recipient rats that were endocrinologically manipulated to induce AU or DU. Cells were also isolated from these AU or DU as mixed or sorted RNA＋ cells and sub-transplanted in recipient rats treated appropriately to induce AU or DU, respectively. Cells obtained from AU in grafts gave rise to clonal AU and from DU in grafts to DU on sub-transplantation in appropriate recipients. When adrenalectomized recipient WF rats co-grafted with MtT W10 received daily subcutaneous injections of hydrocortisone for periods of 21 days following the PHA＋ cell transplantation, AU, instead of DU, were developed. The histologies of these secondary AU and DU were not different from those of the primary AU and DU. Casein and laminin proteins were demonstrated by immunocytochemical staining of primary and secondary AU. Electron micrographs also demonstrated that AU were composed of secretory cells with milk protein in the cytoplasm. DU were composed of little or non-secretory ductal epithelial cells. These AU and DU also secreted large amounts of lipids. Clonogenic cells were more common in DU than in AU. Thus, AU and DU contain persistent subpopulations of clonogenic stem-like cells.

• 한국축산식품학회지
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• 제39권1호
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• pp.23-34
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• 2019

Fat reduction in the formulation of cheese emulsion causes problems in its flowability and functional characteristics during spray-dried cheese powder production. In order to eliminate these problems, the potential of using microparticulated whey protein (MWP) in cheese emulsions was examined in this study. Reduced-fat white-brined cheese emulsions (RF) with different dry-matters (DM) (15%, 20%, and 25% excluding emulsifying salt) were produced using various MWP concentrations (0%-20% based on cheese DM of emulsion). Their key characteristics were compared to full-fat cheese emulsion (FF). MWP addition had no influence on prevention of the phase separation observed in the instable group (RF 15). The most notable effect of using MWP was a reduction in apparent viscosity of RF which significantly increased by fat reduction. Moreover, increasing the amount of MWP led to a decrease in the values of consistency index and an increase in the values of flow behavior index. On the other hand, using high amounts of MWP made the emulsion more liquid-like compared to full-fat counterpart. MWP utilization also resulted in similar lightness and yellowness parameters in RF as their full-fat counterparts. MWP in RF increased glossiness and flowability scores, while decreased mouth coating scores in sensory analyses. Fat reduction caused a more compact network, while a porous structure similar to FF was observed with MWP addition to RF. In conclusion, MWP showed a good potential for formulation of reduced-fat cheese emulsions with rheological and sensorial characteristics suitable to be used as the feeding liquid in the spray drying process.

• 한국도시환경학회지
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• 제18권4호
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• pp.465-471
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• 2018

본 연구에서는 축산계 현장정밀조사를 통해 정부공식 자료로 사용되고 있는 전국오염원조사 결과의 정확성을 확인하고 이에 기초하여 합리적인 가축분뇨관리방안을 제시하였다. 양쪽의 조사결과는 가축사육시설수에서 17.7%, 젓소사육두수에서 39.6%, 돼지분뇨 처리방법에서 41.6%로 가장 큰 차이를 나타냈다. 가축분뇨처리에서 가장 문제가 되고 있는 돼지의 경우가 가장 큰 차이를 보이는 주요 이유는 농경지 단위면적당 퇴비 사용량에 대한 법적 기준이 없어 개별처리 대상 농경지(과수원 포함)의 상당수가 위탁처리비의 절감을 위해 가축분뇨 매립장의 역할을 하고 있기 때문인 것으로 추정할 수 있다. 한편 하천인근의 농경지에 야적되어 있는 방치축분의 67%가 비가림 시설이 없어 비가 올 경우에 방치축분 더미가 그대로 하천으로 흘러 들어갈 수 있었다.

• 한국식품과학회지
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• 제29권5호
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• pp.1052-1056
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• 1997

우유 casein단백질을 trypsin, alcalase, neutrase, protamax, S. aureus type V8 등의 단백질분해효소를 이용하여 가수분해시키고 생성된 peptide의 철분가용화능을 측정하였을 때, trypsin과 alcalase에 의해 생성된 peptide들이 pH 6의 조건에서 각각 6.42와 $2.37\;{\mu}g/mL$를 가용화시키는 능력을 보였으며 그외의 protease들은 $1\;{\mu}g/mL$내외의 철분가용화능을 보였다. Trypsin과 alcalase에 의해 생성된 peptide를 역상 column으로 10개의 분획으로 나누어서 각각의 분획의 pH6에서의 철분가용화능을 측정한 결과, trypsin의 경우 분획 5에서 가장 높은 철분가용화능$(2.33\;{\mu}g/mL)$이 발견되었으며 alcalase의 경우에는 분획 7이 가장 높은 철분가용화능$(1.56\;{\mu}g/mL)$을 보였다. 이들 철분과 결합력이 있는 peptide를 분리하기 위하여 IMAC의 방법을 이용하여 철분을 chelating sepharose fast flow column에 고정화 시키고 이들 철분에 흡착하는 peptide의 분리를 시도한 결과, trypsin이나 alcalase에 의해 생성된 peptide중 철분을 가용화시키는 능력이 높은 peptide들이 IMAC에 의해 효과적으로 분리되었다.

• 수산해양기술연구
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• 제27권4호
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• pp.278-285
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• 1991

현재 사용되고 있는 전개판의 성능을 보다 향상시키기 위한 방안으로 비행기의 익이론에 기초를 두고, 전개판의 경계층을 흡입하거나 제거하는 방법 중에서 역류역을 흡입하는 슬롯(slot)을 전개판에 적용하였다. 성능분석을 위해서 단순만곡형전개판에 슬롯이 없는 기준형과 슬롯의 위치에 따른 5종의 모형전개판에 대하여 성능실험과 가시화실험을 통하여 그 성능과 유체역학적 특성을 비교해 보았다. 실험결과를 요약하면 다음과 같다. \circled1 최대전개력계수는 0.6C, 0.4C, 기준형, 0.8C, 0.2C의 순으로, 슬롯의 위치 0.6C인 전개판이 영각 27$^{\circ}$에서 1.59로 가장 우수하였다. \circled2 항력계수는 슬롯의 위치가 후연으로 갈수록 감소하며, 슬롯을 준 경우가 기준형보다 작게 나타났다. \circled3 양항비는 0.6C, 0.4C, 0.8C, 0.2C, 기준형의 순으로 모두 기준형보다 높게 나타났다. \circled4 0.2C, 0.4C 및 0.6C의 전개판이 기준형과 0.8C의 전개판보다 박리가 후연에서 발생하였다. \circled5 전개판의 전.후면에서 유속차는 영각 15$^{\circ}$~25$^{\circ}$까지는 점차 증가하고, 30$^{\circ}$에서는 감소하는 것으로 나타났다. \circled6 박리역의 크기는 0.6C의 전개판에서 가장 적게 나타났다.

• 분석과학
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• 제23권3호
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• pp.240-246
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• 2010

Salicylaldoxime (SA)이 내포되어 있는 미세결정 p-dichlorobenzene 흡착제(p-dichlorobenzene-SA)를 이용하여 시료에 흔적량으로 들어있는 Cu(II)를 예비농축시킨 후 불꽃 원자흡수분광법으로 정량하는 방법을 개발하였다. 시료 용액의 pH, 킬레이트제 salicylaldoxime의 양, 흡착제 p-dichlorobenzene-SA의 양 그리고 시료 용액의 흐름속도 등 여러 실험조건을 최적화하였다. 여러 공존이온에 대한 방해효과를 조사한 결과, $CN^1$가 다른 이온들보다 비교적 심하게 방해하였다. $1\;{\mu}g\;mL^{-1}\;CN^-$에 의한 방해효과는 Ni(II)를$20\;{\mu}g\;mL^{-1}$ 되도록 조절한 결과, 완전히 제거할 수 있었다. 본 방법으로 얻은 직선 감응범위, 상관계수($R^2$) 및 검출한계는 각각 $3.0\sim100\;ng\;mL^{-1}$, 0.9901, 및 $3.1\;ng\;mL^{-1}$ 이었다. 본 방법을 실제 시료에 적용가능 여부를 확인하기 위해 수용액 시료(폐수, 저수지물 및 시냇물)와 식품시료(오렌지 쥬스, 생계란 및 탈지분유)에 응용하였다. 회수율은 93~104% 범위이었으며, ICP-MS를 이용하여 직접 측정한 값과 본 방법으로 측정한 값을 비교한 결과, 95% 신뢰수준에서 잘 일치하였다. 본 방법을 쌀가루 인증표준물질(certified reference material, CRM) 시료에 응용해 보았으며 좋은 결과를 얻었다. 실험 결과들로부터 본 방법은 여러 실제 시료에 들어있는 Cu(II)를 농축 및 정량하는데 응용할 수 있음을 확인하였다.

• 한국수정란이식학회지
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• 제30권2호
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• pp.73-82
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• 2015

This study was designed to evaluate the possibility of increase through dairy female offspring's ratio by transfer of pre-selected transferrable blastocyst that was produced by pre-selected X-bearing semen with OPU derived oocytes. Elite dairy female cow is demanded strongly compared with male, the so called, farmer wants to produce only an elite female dairy offspring as a candidate female dairy cow for producing milk. In our study, we selected 2 elite dairy bull semen from National Agricultural Cooperative Federation to pre-select X-bearing semen and 5 elite dairy female cows as donor for collecting of OPU derived oocytes. OPU derived embryo production system was carried out an aspiration of immature oocytes from 5 donor cows 2 times per week, total 200 times for 2 to 7 months by an ultrasonographic guided follicular aspiration system and then produced in vitro-produced blastocysts by in vitro maturation, fertilization and culture. Dairy donor semen selected H-319, 320 bull in National Agricultural Cooperative federation was sorted X-bearing semen by flow-cytometer and frozen for using IVF with OPU derived oocytes. Donor cows were selected 5 elite dairy cows from Gyeongju Dairy Cow Community and then disease tests such as 4 kinds of disease before selecting was checked. Oocyte proportion of grade 1 to 3 from total collected oocytes was significantly lower in donor A and B than those in donor C, D and E (82.16 and 70.03% vs. 90.0, 91.78 and 93.57%), respectively (p<0.05). However, number of oocytes per session in donor A, C and E was significantly higher than those in donor B and D ($7.77{\pm}3.26$, $5.85{\pm}2.10$ and $7.03{\pm}2.14$ vs. $4.68{\pm}2.61$ and $5.21{\pm}1.97$ oocytes), but donor A was significantly higher than donor C (p<0.05). Development to blastocyst in donor B, C and E was significantly higher than those in donor A and D (31.0, 25.0 and 25.0% vs. 14.3 and 4.5%), but donor A was not different in donor C and E (p<0.05). Nine out of 10 blastocysts (90.0%) derived from OPU blastocysts were confirmed male embryos that was induced with Y-bearing semen to confirm sex ratio only. Total 96 blastocysts derived from female bearing semen were transferred into synchronized recipients and then confirmed 42 recipients (43.8%) pregnancy rate, 36 offspring (37.5%) and 91.7% female sex ratio (33 female vs. 3 male offspring). Taken together all data, elite dairy female offspring could be produced effectively by in vitro production system between pre-selected x-bearing semen and OPU derived oocytes that would be influential breeder in the breeding of dairy farm to increase effectively elite dairy offspring ratio as well as net income in the dairy farmer.