• Korean Chemical Engineering Research
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• 제60권3호
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• pp.392-397
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• 2022

Methane is one of the major greenhouse gases, recently, the biotechnological conversion from methane to high-value added chemicals have emerged as an effort to reduce methane gas emission. In this study, we optimized ectoine bio-milking conditions in which cells were repeatedly used to improve intracellular and extracellular ectoine yield from methane by using Methylomicrobium alcaliphilum 20ZDP2. First, the cultivation and intracellular ectoine accumulation conditions were optimized with respect to the growth phase and medium salinity to achieve the highest yield of synthesis. Second, ectoine excretion was optimized by determining the ectoine secretion time (15 min) in appropriate medium salinity under hypoosmotic conditions (1% NaCl). Finally, bio-milking of ectoine was successfully repeated more than 10 times using M. alcaliphilum 20ZDP2, and the ectoine yield was improved up to 129.29 mg/ DCW g.

• 한국축산시설환경학회지
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• 제14권3호
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• pp.149-158
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• 2008

본 시험은 젖소농가에서 보유하고 있는 여러가지 형태의 착유시스템에 대하여 계절별 세척수의 발생량과 이화학적 특성을 알아보고자 바켓식, 파이프라인식, 텐덤식, 헤링본식 등 착유시스템 유형별로 각각 3농가를 선정하여 계절별로 조사를 실시하였으며, 그 결과는 다음과 같다. 1. 착유시스템 유형별 세척수 발생량은 텐덤식과 헤링본식에서 많았으며 바켓식이 적었다 (P<0.05). 2. 착유작업별 세척수 발생량은 착유기 세척에 가장 많은 량의 세척수를 사용하였으며 여름철의 경우 텐덤식 $398.8{\ell}$, 헤링본식 $407.7{\ell}$가 다른 착유시스템보다 많은 세척수를 사용하였다 (p<0.05). 3. 착유과정에서 발생하는 세척수 발생량을 조사한 결과, 평균 $15.4{\ell}$/두였으며, 계절별로는 여름이 $16.4{\ell}$로 가장 많은 세척수가 발생되었다. 4. 착유과정에서 발생하는 세척수의 $BOD_5$는 착유실 세척시 발생하는 세척수가 $906.4mg/\ell$로 가장 높았으며, 유두 세척시 가장 낮은 $212.4mg/\ell$로 나타났다. COD, SS 등도 착유실 바닥세척시 가장 높은 경향을 보였다. 5. 세척수의 이화학적 특성은 pH는 $7.3{\sim}8.2$의 범위로 착유작업 단계에 따라 차이를 나타내었으며, 착유작업 후 착유실 외부로 흘러나오는 배출수의 $BOD_5$, COD, SS, T-N, T-P는 각각 731.2, 479.0, 751.6, 79.1, $14.7mg/\ell$였다. 이상의 시험결과를 종합해 보면 착유시스템 유형별 세척수 발생량은 바켓식, 파이프 라인식, 텐덤식 및 헤링본식이 각각 143.9, 487.9, 914.0, $856.7{\ell}$로 조사되었으며, 착유과정에서 발생하는 세척수량은 착유우 두당 $15.4{\ell}$로 착유시스템 유형 및 착유우 사육두수에 따라 낙농가도 농가실정에 맞는 세척수 처리시설 및 용량을 확보해야 할 것으로 판단된다.

• Journal of Animal Science and Technology
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• 제65권1호
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• pp.244-257
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• 2023

The study aimed to investigate the effect of low-frequency oscillations on the cow udder, milk parameters, and animal welfare during the automated milking process. The study's objective was to investigate the impact of low-frequency oscillations on the udder and teats' blood circulation by creating a mathematical model of mammary glands, using milkers and vibrators to analyze the theoretical dynamics of oscillations. The mechanical vibration device developed and tested in the study was mounted on a DeLaval automatic milking machine, which excited the udder with low-frequency oscillations, allowing the analysis of input parameters (temperature, oscillation amplitude) and using feedback data, changing the device parameters such as vibration frequency and duration. The experimental study was performed using an artificial cow's udder model with and without milk and a DeLaval milking machine, exciting the model with low-frequency harmonic oscillations (frequency range 15-60 Hz, vibration amplitude 2-5 mm). The investigation in vitro applying low-frequency of the vibration system's first-order frequencies in lateral (X) direction showed the low-frequency values of 23.5-26.5 Hz (effective frequency of the simulation analysis was 25.0 Hz). The tested values of the first-order frequency of the vibration system in the vertical (Y) direction were 37.5-41.5 Hz (effective frequency of the simulation analysis was 41.0 Hz), with higher amplitude and lower vibration damping. During in vivo experiments, while milking, the vibrator was inducing mechanical milking-similar vibrations in the udder. The vibrations were spreading to the entire udder and caused physiotherapeutic effects such as activated physiological processes and increased udder base temperature by 0.57℃ (p < 0.001), thus increasing blood flow in the udder. Used low-frequency vibrations did not significantly affect milk yield, milk composition, milk quality indicators, and animal welfare. The investigation results showed that applying low-frequency vibration on a cow udder during automatic milking is a non-invasive, efficient method to stimulate blood circulation in the udder and improve teat and udder health without changing milk quality and production. Further studies will be carried out in the following research phase on clinical and subclinical mastitis cows.

• Journal of Animal Science and Technology
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• 제56권4호
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• pp.13.1-13.5
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• 2014

The production performance of multiparous lactating Sahiwal cows (n = 24) was evaluated according to both milking frequency and method. Selected animals were randomly divided into four groups containing six animals each under a completely randomized design. Cows in groups A & B were milked by the hand milking method three times per day, respectively. Similarly, cows in groups C & D were milked by the machine milking method two and three times per day, respectively. All animals were maintained under uniform feeding and management conditions. Dry matter intake was high in animal groups milked three times per day, and it remained unchanged between the hand and machine milking methods. Milk yield was higher (P < 0.05) in cows milked three times compared to those milked twice per day, and it did not differ between hand and machine milking methods. Milk fat percentage was higher (P < 0.05) in cows milked twice per day compared to those milked three times using both machine and hand milking methods. The percentage of total solids showed a similar pattern as the fat percentage. However, percentages of protein, lactose, and non-fat solids in milk were not significantly different (P > 0.05) among the treatment groups. Collectively, the results show that milking three times per day instead of twice at 8-hour intervals can enhance milk yield in Sahiwal cows using both hand and machine milking methods.

• Journal of Animal Science and Technology
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• 제55권6호
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• pp.489-500
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• 2013

Daily milk yields on test days were estimated using morning or afternoon partial milk yields collected by official agencies and the accuracy of the estimates was determined. Test-day data for milk yields consisted of 3,156,734 records of AM/PM partial milking measurements of 255,437 milking Holstein cows from 3,708 farms collected from December 2008 to April 2013. A linear regression model (LRM) was applied to estimate daily milk yields using alternate AM/PM milk yield records within lactation stages, milking intervals, and parities on every daily milk yield. The alternate statistical approach was a non-linear hierarchical model (NHM) in which Brody's growth function was implemented by reflecting an animal's physiological milk production cycle. When compared with LRM, daily milk yields predicted by the NHM were assumed to be functionally related to day in milk (or lactation) stage, milking intervals, and partial milk yields. Since the results were in terms of accuracies based on comparisons of different statistical models, accuracies of estimates of daily milk yields by NHM were close to those determined by the LRM. The average of these accuracies was 0.94 for AM partial milk yields and 0.93 for PM partial milk yields for first calving cows. However, the accuracies of AM/PM milk yield estimations from cows under a calving stage higher than the first parity were 0.96 and 0.95, respectively. Correlations between the estimated daily milk yields and the actual daily milk yields ranged from 0.96~0.98. These accuracies were lower for unbalanced AM/PM milking intervals and the first calving cows. Overall, prediction of daily milk yields by NHM would be more appropriate than by LRM due to its flexibility under different milk yield-related circumstances, which provides an idea of the functional relationship between milking intervals and days in milk with daily milk yields from statistical viewpoints.

• Journal of the Korean Data and Information Science Society
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• 제24권3호
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• pp.487-493
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• 2013

본 연구의 목적은 비유속도형질들에 대한 유전모수를 추정함으로서 개량형질로서의 가능성을 분석하여 젖소개량목표 설정 시 기초자료를 제공하는데 있다. 착유개시 3분 이내 평균 착유량 (3MG)은 8.97kg으로 총 착유량의 57%가 3분 이내에 비유되는 것으로 나타났으나 권장수치 70%에 비하여 낮게 나타났으며, 순간최고유속 (HMF), 주착유시평균유속 (DMHG)의 평균치는 각각 3.66kg/min와 2.43kg/min으로 각각의 권장수치 4.0~5.0kg/min과 3.0~4.0kg/min보다 낮게 나타남으로서 국내 젖소의 비유속도는 외국에 비해 느린 것으로 나타났다. 순간최고유속(HMF), 분당 최고유속 (HMG)과 주착유시간 분당평균유속 (DMHG)의 유전력은 각각 0.35, 0.31과 0.29로서 중도의 유전력을 지닌 개량에 적합한 형질로 판단되었다. 그리고 총착유량 (MGG)과 주착유시간 분당 평균유속 (DMHG)의 유전상관은 0.591이었으며, 비유속도 관련형질 (HMF, HMG, DMHG)간의 유전상관은 0.889 0.997의 범위를 나타내었다.

• 한국축산시설환경학회지
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• 제8권3호
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• pp.165-170
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• 2002

This study was carried out to measure the 3D-distance of a cow model teat for an application possibility on Robotic Milking System(RMS). A teat recognition algorithm was made to find 3D-distance of the model by using Gonzalrez's theory. Some of the results are as follows. 1 . In the distance measurement experiment on the test board, as the measured length, and the length between the center of image surface and the measured image point became longer, their error values increased. 2. The model teat was installed and measured the error value at the random position. The error value of X and Y coordinates was less than 5㎜, and that of Z coordinates was less than 20㎜. The error value increased as the distance of camera's increased. 3. The equation for distance information acquirement was satisfied with obtaining accurate distance that was necessary for a milking robot to trace teats, A teat recognition algorithm was recognized well four model cow teats. It's processing time was about 1 second. It appeared that a teat recognition algorithm could be used to determine the 3D-distance of the cow teat to develop a RMS.

• Journal of Animal Science and Technology
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• 제51권4호
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• pp.265-272
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• 2009

본 연구는 임실군 관내 16농가를 선정하여 총 486두에 대한 비유기록을 수집하였으며, 얻어진 결과는 다음과 같다. 평균 비유개시 3분이내 유량(3MG)은 7.44 kg으로 총 유량의 55%가 3분이내에 비유되는 것으로 나타났고 평균 우유속 거품함량(SPL)은 33.93%였으며, 평균 후착유 유량은(MNG)은 0.14 kg으로 총 유량의 1%에 불과하였다. 순간최고유속(HMF), 분당최고유속(HMG)과 주착유시평균유속(DMHG)에 대한 평균치는 각각 3.03 kg/min, 2.94 kg/min과 2.05 kg/min으로 임실군 젖소군의 비유속도는 대체적으로 느린 것으로 조사되었다. 비유개시부터 유속 500 g/min 도달시간(tS500)은 평균 0.23분(약 14초) 이었으며, 총비유 시간(tMGG)의 평균은 7.75분이었다. 평균 과착유소요시간(tMBG)은 0.58분(35초) 이었으며, 후착유소요시간(tMNG)은 평균 0.42분(14초) 걸리는 것으로 조사되었다. 최고유속시 전기전도도(ELHMF)와 비유개시시 최고전기전도도(ELAP)의 평균은 각각 6.81 mS/cm와 7.58 mS/cm로 조사되었고 최고유속이후 최고전기전도도(ELMAX)는 평균 7.48 mS/cm로 나타났으며, 비유초기와 최고유속의 전기전도도 차이(ELAD)는 평균 0.61 mS/cm로 나타났다. 총비유량은 주착유시 평균유속(DMHG), 주착유시간(tMHG), Plateau 비유 소요시간(tPL), 비유하강기 소요시간(tAB)과 총착유 시간(tMGG)에 대하여 0.35~0.54 범위의 정(+)의 상관관계를 나타낸 반면, 과착유시간(tMBG)과 우유속 거품함량(SPL)과는 각각 -0.11과 -0.27의 부(-)의 상관을 나타내었다. 주착유시 평균유속(DMHG)이 증가하면 총비유시간(tMHG), Plateau 비유 소요시간(tPL), 비유하강기 소요시간(tAB), 총비유시간(tMGG)과 우유속 거품함량(SPL)은 감소하는 것으로 나타났다. 비유개시시 전기전도도가 높은 개체의 우유는 체세포 수가 적은 반면 최고 비유기 이후 최고전도도가 높은 개체의 우유는 체세포 수가 높은 것으로 나타났다. 따라서 비유상태를 정기적으로 점검하고 착유 및 비유에 대한 표준안을 바탕으로 착유를 실시하면 유량과 유질의 향상을 기대할 수 있다고 판단되었다.

• Journal of Preventive Medicine and Public Health
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• 제43권3호
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• pp.205-212
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• 2010

Objectives: The prevalence of work-related musculoskeletal symptoms (WMS) among Korean dairy farmers has not been investigated. The purpose of this study was to assess the prevalence of WMS and to evaluate the relationship between WMS and risk factors. Methods: Self-developed questionnaires including the questionnaire developed by the Korean Occupational Safety and Health agency (KOSHA) were used to investigate WMS among dairy farmers in Gyeonggi Province, Korea. We informed selected dairy farmers about the study and sent the questionnaires by registered mail. They visited a public health center nearby or a branch of public health center on the appointed date and skillful researchers identified or conducted the questionnaires by interview. We analyzed 598 (32.8%) of the 1824 dairy farmers. Multiple logistic regression was implemented to estimate the odds ratios of risk factors. Results: The mean age of the respondents was $50.4{\pm}8.7$ years and the proportion of males was 63.0%. The prevalence of WMS at any site was 33.3%. The prevalence of neck WMS was 2.2%, shoulders 10.0%, arms/elbows 5.0%, hands/wrists/fingers 4.2%, low back 11.5%, and legs/feet 11.7%. The adjusted odds ratio of low back WMS for milking 4 or more hours per day was 4.231 (95% Cl = 1.124 - 15.932) and statistically significant. Low back WMS (2.827, 95% Cl = 1.545 - 5.174) was significantly decreased by education. Conclusions: Low back WMS increased with milking hours and milking 4 or more hours per day was significantly associated with low back WMS. Low back WMS was significantly reduced with education. We hope that there will be increased attention about WMS in dairy farmers and the subject of future investigations.

• Animal Bioscience
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• 제37권2호
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• pp.173-183
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• 2024

Objective: This study aimed to evaluate whether the methane (CH₄) to carbon dioxide (CO₂) ratio (CH₄/CO₂) and methane-related traits obtained by the sniffer method can be used as indicators for genetic selection of Holstein cows with lower CH₄ emissions. Methods: The sniffer method was used to simultaneously measure the concentrations of CH₄ and CO₂ during milking in each milking box of the automatic milking system to obtain CH₄/CO₂. Methane-related traits, which included CH₄ emissions, CH₄ per energy-corrected milk, methane conversion factor (MCF), and residual CH₄, were calculated. First, we investigated the impact of the model with and without body weight (BW) on the lactation stage and parity for predicting methane-related traits using a first on-farm dataset (Farm 1; 400 records for 74 Holstein cows). Second, we estimated the genetic parameters for CH₄/CO₂ and methane-related traits using a second on-farm dataset (Farm 2; 520 records for 182 Holstein cows). Third, we compared the repeatability and environmental effects on these traits in both farm datasets. Results: The data from Farm 1 revealed that MCF can be reliably evaluated during the lactation stage and parity, even when BW is excluded from the model. Farm 2 data revealed low heritability and moderate repeatability for CH₄/CO₂ (0.12 and 0.46, respectively) and MCF (0.13 and 0.38, respectively). In addition, the estimated genetic correlation of milk yield with CH₄/CO₂ was low (0.07) and that with MCF was moderate (-0.53). The on-farm data indicated that CH₄/CO₂ and MCF could be evaluated consistently during the lactation stage and parity with moderate repeatability on both farms. Conclusion: This study demonstrated the on-farm applicability of the sniffer method for selecting cows with low CH₄ emissions.