• Journal of Animal Science and Technology
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• v.56 no.2
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• pp.5.1-5.5
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• 2014

The objectives of this study were thus to identify most significant factors that determine milk component yield (MCY) using a meta-analysis and, if possible, to develop equations to predict MCY using variables that can be easily measured in the field. A literature database was constructed based on the research articles published in the Journal of Dairy Science from Oct., 2007 till May, 2010. The database consisted of a total of 442 observed means for MCY from 118 studies. The candidate factors that determine MCY were those which can be routinely measured in the field (e.g. DMI, BW, dietary forage content, chemical composition of diets). Using a simple linear regression, the best equations for predicting milk fat yield(MFY) and milk protein yield (MPY) were $MFY=0.351({\pm}0.068)+0.038({\pm}0.003)$ DMI ($R^2=0.27$), and $MPY=0.552({\pm}0.071)+0.031({\pm}0.002)DMI-0.004({\pm}0.001)$ FpDM (%, forage as a percentage of dietary DM) ($R^2=0.38$), respectively. The best equation for predicting milk fat content (%) explained only 12% of variations in milk fat content, and none of a single variable can explain more than 5% of variations in milk protein content. We concluded that among the tested variables, DMI was the only significant factor that affects MFY and both DMI and FpDM significantly affect MPY. However, predictability of linear equations was relatively low. Further studies are needed to identify other variables that can predict milk component yield more accurately.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.8
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• pp.1073-1082
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• 2012

We first sought to clarify the effects of discounted rate, survival rate, and lactation persistency as a component trait of the selection index on net merit, defined as the first five lactation milks and herd life (HL) weighted by 1 and 0.389 (currently used in Japan), respectively, in units of genetic standard deviation. Survival rate increased the relative economic importance of later lactation traits and the first five lactation milk yields during the first 120 months from the start of the breeding scheme. In contrast, reliabilities of the estimated breeding value (EBV) in later lactation traits are lower than those of earlier lactation traits. We then sought to clarify the effects of applying single nucleotide polymorphism (SNP) on net merit to improve the reliability of EBV of later lactation traits to maximize their increased economic importance due to increase in survival rate. Net merit, selection accuracy, and HL increased by adding lactation persistency to the selection index whose component traits were only milk yields. Lactation persistency of the second and (especially) third parities contributed to increasing HL while maintaining the first five lactation milk yields compared with the selection index whose only component traits were milk yields. A selection index comprising the first three lactation milk yields and persistency accounted for 99.4% of net merit derived from a selection index whose components were identical to those for net merit. We consider that the selection index comprising the first three lactation milk yields and persistency is a practical method for increasing lifetime milk yield in the absence of data regarding HL. Applying SNP to the second- and third-lactation traits and HL increased net merit and HL by maximizing the increased economic importance of later lactation traits, reducing the effect of first-lactation milk yield on HL (genetic correlation ($r_G$) = -0.006), and by augmenting the effects of the second- and third-lactation milk yields on HL ($r_G$ = 0.118 and 0.257, respectively).

• Journal of Nutrition and Health
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• v.37 no.9
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• pp.809-816
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• 2004

The purpose of this study was to evaluate the effect of maternal nutritional status and health behaviors on the concentrations of minerals (Zn, Fe, Ca) and the immunological substances (lactoferrin, sIgA, Iysozyme) in breast milk. Breast milk was collected from 193 healthy Korean women from obstetric clinics and postpartum care centers in Seoul. : 99 colostrum (1 - 5 days postpartum), 33 transitional milk (6 - 10 days postpartum), 61 mature milk (11 - 50 days postpartum). The concentrations of minerals and immunological substance were highest in colostrum and decreased with lactational period. Concentrations of Zn and Fe reduced significantly from colostrum to mature milk, however, Ca concentration stayed constant throughout the lactational period. Contents of lactoferrin, sIgA, and lysozyme were significantly lower in mature milk than in colostrum. Mother's nutritional status, assessed by prepregnancy BMI, had an effect only on colostrum, but not on transition and mature milk. Fe concentration of colostrum was significantly lower in underweight (prepregnancy BMI < 18.5) than in overweight mothers (prepregnancy BMI $\geq$ 23.0). Also lower tendency was observed for sIgA and lysozyme contents, even though the difference was not statistically significant. Pregnancy weight gain had no effect on the breast milk component. Since nutritional factors had some effect on colostrum, the health behaviors of mothers providing colostrum were assessed. The mother's behavior of smoking, drinking, morning sickness, parity, disease, nutrient supplement use had no significant effect on the breast milk component, however, Zn, sIgA, and lysozyme were the somewhat affected components by maternal health behavior.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.93-93
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• 2003

모유의 뮤신 복합체는 rotavirus에 특이적으로 결합하여 항 바이러스활동을 보여주는 것으로 나타났다. 자연 상태에서의 뮤신은 몇몇 작은 분자들과 복합적으로 연합되어 있는데 70kda의 glycoprotein, butyrophilin, 그리고 glycosylated component, lactadherin을 포함하고 있다. 그중 rotavirus에 가장 높은 결합력과 항바이러스 활동을 나타내는 Lactadherin은 모유의 유단백질의 하나인 뮤신과 결합되어 분비되는 당단백질의 하나로 분자량이 46kda이고, 지방구막 속에 연합되어있다. 이러한 배경에서 본 연구에서는 한국 여성의 breast tissue로부터 lactadherin 유전자의 cloning 및 in vitro에서의 발현을 유도하여 lactadherin band만을 purify하였고 여기서 얻은 lactadherin을 항체 생산을 위한 항원으로 사용하여 anti-lactadherin antibody를 확보하였다. 이 항체는 human milk에서의 lactadherin을 동정하는데 사용하였는데 western blot결과 lactadherin을 포함하여 몇 몇 단백질들이 확인되었다. Human milk내 mucin은 몇몇 작은 분자들과 복합체를 형성하는 것으로 확인되어졌는데 70kda의 glycoprotein, butyrophilin 그리고 46kda의 glyxosylated component, lactadherin을 포함하고 있는 milk mucin은 associated molecular임을 확인할 수 있었다.

• Journal of Nutrition and Health
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• v.29 no.9
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• pp.1042-1048
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• 1996

In order to investigate heating rate of commercial milk products in korean market, lactulose content and availability of calcium and ascorbic acid were measured. The pH range for raw and commercial milk was 6.5-6.75, and protein content was 2.5-3.13%. The acid degree value (。SH)showed between 5.3 and 7.1. There were no differences in pH, protein and acid degree among 3 types of milk. The portion ionic Ca content in UHT-milk(32.4%) and pasteurized milk (27%) increased significantly in comparison with raw milk (4.6%). Pasteurization led to loss of 20% ascorbic acid, and losses of UHT-treatment are approximately twice as high. Significant differences of lactulose content between UHT milk and pasteurized milk were observed. Some of UHT milk products showed very high value of lactulose content like sterilized milk. It is well known that the stress caused by indirect UHT treatment is slightly higher compared with the direct process. The results in this experiment suggested that most of UHT milk in korean market may be treated by indirect UHT method. In oder to keep the adventages of milk component, the heating methods of milk have to be reconsidered.

• Journal of Sensor Science and Technology
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• v.23 no.5
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• pp.320-325
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• 2014

Volatile flavor compounds from milk were analyzed and identified by using the analysis methods of headspace solid phase microextraction gas chromatography/mass spectrometry (HSPME-GC/MS) and electronic nose (E-Nose) system. About 30 volatile compounds were identified by HSPME-GC/MS for the fresh and off-flavor milk samples. Also, the correlation between rancidity and ageing days of milk was obtained by the aid of principal component analysis algorithm. It shows that the E-Nose system can identify the various types of milk flavor. These results imply that the analysis method based on the E-nose system can apply to the quality control of milk flavor and the rancidity.

• Journal of Veterinary Clinics
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• v.21 no.4
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• pp.355-362
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• 2004

The purpose of this study was to herd management and control of dairy cows by milk components analysis in Gyeongsangnamdo. Milk components analysis were carried out milk yield (MY), milk fat (MF), milk protein (MP), milk urea nitrogen (MUN) and somatic cell count (SCC) but, milk solid (MS), day of non-pregnant condition (DNPC), and days of primipara (DPRI) involved in report. Dairy farms were divided high group, middle group, low group according to the standard records for milk components. Examination records were divided by farm, parity, year, season and month, the number of samples were 28,957. Feeding management practice and the prediction for the risk possibility of productive disease such as reproductive and metabolic disorders by evaluating fat, protein, solids. Determination of MY, MF, MP, MS were Milkoscan 4,000~5,000 Serier (FOSS Electric Co., Copenhagen, Denmark). Correlation coefficient of milk protein (MP) and milk solid (MS) was ascertain r=0.759. SCC was ascertain 372.8$\pm$11.34 (thousand unit) and DNPC was ascertain 155.3$\pm$5.15 (days) in seven parity.

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.91-97
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• 1974

This paper was developed for production of the humanized milk, comprising similarly to the composition and characteristic of human milk. Humanized milk of superior quality can be made directly from the fresh raw milk mixed vegetable oil, corn syrup, whey powder, ${\beta}-lactose$, sugar, vitamin, ${\beta}-carotene$ and minerals showing formulation of the humanized milk at table 2. The improving effects of adding vegetable oil and corn syrup are both more reformed the chemical and physical properties of humanized milk. The former enhanced the essential fatty acid and energy source in this product, the latter has the most solving function in water and induced amount of emulsion and stabilizer. The products contain about 13% protein, 23% fat, 58.3% carbohydrate, 2% ash and ensue reasonably balance of essential amino acid, poly-unsaturated fatty acid for the requirement of infants and controlled component of the humanized milk such as human milk.

• Journal of Dairy Science and Biotechnology
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• v.28 no.1
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• pp.9-16
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• 2010

Adolescents grow rapidly and have lots of schoolwork for entrance examination, so good nutrition is very important to them. However, adolescents tend to have a poor dietary behavior including frequent consumption of empty calorie foods and skipping breakfast. In particular, frequency of drinking milk has been low among Korean adolescents, thus their dietary calcium intakes has been low. Undesirable dietary behavior of adolescents is a risk factor for poor nutrition, obesity and chronic disease of them. Milk is a good source for calcium, high quality of protein, vitamin and bioactive compounds including anti-obesity component, thus it has been reported that milk helps improvement of dietary nutrient adequacy and physical growth, increment of bone mineral density, and prevention of obesity and chronic diseases. Therefore, milk consumption of adolescents should be encouraged in order to help their nutritional status, physical growth and health.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.1
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• pp.21-25
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• 1990

Fructo-oligosaccharides are found in many plants, such as onion, burdock and wheat. They are not well hydrolyzed by digestive enzymes in animals, but are peculiarly assimilated by Bifidobacterium and some useful bacteria. In our previous experiment (Kobayashi et al., 1987) it was suggested that they were effective in decreasing energy loss in the metabolism of dairy calves. In the present study, the effects of fructo-oligosaccharides on body weight, milk-yield and milk-components (fat, protein and solids-not-fat) were investigated in dairy cows. Lactating cows were fed a standard diet containing fructoligo saccharides at 18.70g, 9.35g and 0.0g (control) per 100kg body weight, day for three weeks. Neither treatments significantly affected any of the parameters examined. The fructo-oligosaccharides were assumed to be hydrolyzed by rumen microorganisms and hardly to affect the bacterium florae in the intestines of the lactating cows.