• 제목/요약/키워드: feed concentration

검색결과 1,600건 처리시간 0.029초

빈산소와 철에 대한 넙치, Paralichthys olivaceus의 생태생리적 반응 및 회복 I. 넙치의 성장에 미치는 철의 영향 (Ecophysiological Responses and Subsequent Recovery of Olive Flounder, Paralichthys olivaceus, Exposed to Hypoxia and Iron. I. Effect of Iron Concentration on the Growth of Olive Flounder)

  • 강주찬;김창훈
    • 한국수산과학회지
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    • 제32권3호
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    • pp.353-358
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    • 1999
  • 본 연구는 연안역의 환경오염 및 양식용수의 이용과정에서 파생될 수 있는 철오염에 따른 넙치의 생산성을 간접적으로 파악하기 위하여 이에 관련된 넙치의 성장, 섭식 및 사료효율에 미치는 철의 영향을 검토하였다. 넙치의 성장률은 각 실험의 대조구 혹은 같은 철농도에서도 비교적 큰 폭으로 변동하였으나, 평균 상대성장률은 대조구 $97.8\%$에 비해 철농도 0.1. 0.5. 1.0, 5.0, 10.0mg/$\ell$에서 각각 103.8, 97.3, 95.8, 87.0 및 $69.2\%$로 철농도 1.0mg/$\ell$이하에서는 유사한 경향을 보였으나, 5.0mg/$\ell$이상의 농도에서 유의한 감소를 나타내었다. 섭식율은 대조구를 비롯하여 철농도 5.0mg/$\ell$이하에서는 유사한 값을 나타내었으나, 10.0mg/$\ell$농도에서 감소하였고, 상대섭식율은 철농도 10.0 mg/$\ell$에서 유의한 감소를 보였고, 5.0mg/$\ell$ 이하의 농도에서는 거의 일정하게 나타났다. 사료효율은 철농도 0.5mg/$\ell$ 이하에서 대조구와 유사한 경향을 나타내었으나, 1.0mg/$\ell$농도 이상부터 감소하는 경향을 보였다. 그러나, 상대사료 효율은 철농도 5.0mg/$\ell$이상의 농도에서는 대조구에 비해 유의한 감소가 인정되었다.

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나권형 역삼투 모듈에 의한 Cephalosporin C의 농축분리에 관한 실험연구 (Experimental Study on Separation of Cephalosprotin C by Spiral-Wound Reverse Osmosis Module)

  • 신동엽;류정;이용철
    • 공업화학
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    • 제10권4호
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    • pp.563-567
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    • 1999
  • 용질배제율이 우수한 나권형 FT-30 폴리아미드 복합막을 상용하여 cephalosporin C를 농축하기 역삼투 농축실험을 하였다. $4{\sim}20kg/cm^2$의 압력과 100~1000 mg/L의 농도, 그리고 2.8과 5.6 L/min의 유속을 갖는 실험 조건하에서 cephalosporin C 수용액의 수투과율과 용질의 배제율 및 물질전달 계수를 구하였다. Cephalosporin C를 분리하는데 있어서 압력이 증가함에 따라 투과 플럭스가 증가하는 것으로 나타났다. 이 결과는 Kedem-Katchalsky 모델에서 예측한 것과 일치하였다. 그리고 배제율은 1에 가까웠다. 또한 공급액의 농도가 증가할수록 cephalosporin C의 배제율은 낮아지는 것으로 나타났다. 배제율은 고농도보다는 저온도에서 높게 나타났으나 그 감소 정도는 작았다.

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투과증발법을 이용한 감귤 Essence Aroma 모델액의 농축 (Concentration of Citrus Essence Aroma Model Solution by Pervaporation)

  • 이용택;박중원;신동호
    • 멤브레인
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    • 제16권1호
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    • pp.68-76
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    • 2006
  • 본 연구는 투과증발법을 이용하여 수용액 중 미량의 감귤 향 성분을 농축하는 방법으로, 4종류의 실록산계 고분자 복합막을 이용하여 막 종류와 구조에 따른 투과 특성을 살펴보았다. 또한 최적의 막을 선정하여 공급액의 온도와 농도, 순환 유속에 따른 투과 특성을 살펴보고, 이를 resistance-in series model을 이용하여 해석하였다. 4종류의 실록산계 고분자 복합막을 통한 감귤 essence aroma 모델액의 투과 실험에서 지지층이 polyvinylidene fluoride (PVDF)이고 활성층이 polyoctylmethyl siloxane (POMS)인 막이 가장 높은 향 성분 플럭스와 농축계수 값을 나타내었으며, 공급액의 온도와 농도, 순환유속을 변화시키며 투과 실험을 하였다. 그 결과 공급액의 온도와 농도가 증가됨에 따라 향성분의 플럭스는 증가하고 농축계수 값은 감소하였으며 순환유속이 증가됨에 따라 향성분의 플럭스와 농축계수 값 모두 증가하였다.

Effects of soft pellet creep feed on pre-weaning and post-weaning performance and intestinal development in piglets

  • Chen, Hao;Wang, Chunwei;Wang, You;Chen, Yilin;Wan, Meng;Zhu, Jiadong;Zhu, Aixia
    • Animal Bioscience
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    • 제34권4호
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    • pp.714-723
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    • 2021
  • Objective: This study aimed to determine the effects of soft pellet creep feed (SPCF) on growth performance and intestinal development in piglets. Methods: A total of 18 sows and their litters of crossbred piglets (14±2 days, 3.73±0.72 kg) were assigned to one of three dietary groups receiving i) powder creep feed (PCF), ii) hard pellet creep feed (HPCF) or iii) SPCF during the pre-weaning period. After weaning, piglets were selected for continuous evaluation of the three diets on growth performance and intestinal health. Results: In the pre-weaning period, the average daily feed intake and average daily dry matter intake were significantly higher in the SPCF group than the HPCF group (p<0.05). In the post-weaning and entire experimental period, the different diets had no significant effect on growth performance. At 10 d after weaning, the serum glucose concentration was lower in the SPCF group (p<0.05) than the other groups; a higher (p<0.05) villus height and lower (p<0.05) crypt depth in the jejunum were also observed in the SPCF group than the other groups; Meanwhile, in the duodenum and jejunum, the SPCF group had a higher (p<0.05) villus height to crypt depth ratio than the other groups; Furthermore, the higher (p<0.05) threshold cycle values of lactic acid bacteria and lower (p<0.05) threshold cycle values of Clostridium, Enterobacter and Escherichia coli were also observed in the SPCF group, and the sucrase and maltase activity was higher (p<0.05) in the SPCF group than the other groups in duodenum and ileum. Conclusion: The SPCF improved pre-weaning feed intake and decreased the negative effects of weaning stress in the intestine in piglets.

고농도 세포배양에서 Bacillus thuringiensis의 세포 성장과 포자 형성 속도 (Growth Kinetics and Sporulation of Bacillus thuringiensis in High Cell Density Culture)

  • 강병철;장호남
    • KSBB Journal
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    • 제16권1호
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    • pp.30-35
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    • 2001
  • 유가식배양과 세라믹 막을 장착한 생물반응기에서 운전인 TCRC 조업을 통해서 Bacillus thuringiensis의 고농도 세포배양을 실시하였다. 유가식 배양에서 B. thuringiensis의 세포 성장은 선형적으로 증가하였고, 이것은 세포성장 모델리의 결과와 잘 맞았다. 낮은 세포 성장속에도 불구하고 유가식 배양동안에 포자형성은 관찰할 수 없었고, 이것은 연속배양의 결과와는 반대였다. 유가식 조업 후에 회분식 배양으로 바꾸면 300 g/L의 포도당 공급 농도를 사용했을 때 2.7$\times$$10^9$ CFU/mL 의 포자농도를 얻었다. 생물반응기내에 세라믹 막을 장착한 TCRC 조업에서 포도당 공급 농도의 영향을 결정하였다. 50 g/L의 포도당 농도를 사용했을 때 TCRC 조업에서 82.5 g-cell/L에 해당하는 최대 세포농도 1.8$\times$$10^{10}$ CFU/mL 를 얻었다. TCRC에서 세포성장은 선형적으로 증가하였고 포도당 농도는 제한되었는데 이것은 세포성장은 모델링의 결과와 잘 일치하였다. 1 g/L의 포도당을 공급한 경우 이외에는 TCRC 조업 동안에 포자형성을 관찰할 수 없었다. 50 g/L의 포도당을 공급한 경우 TCRC조업 후에 회분식 배양으로 전환시키면 1.2$\times$$10^{10}$ CFU/mL 의 포자농도를 얻었고, 이것은 연구된 여러 배양형태 중에 가장 높은 포자농도이다. 이 때 최적의 포도당 공급속도는 0.55 g glucose/h로 공급하였을 때였다.

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Influence of Level of Feed Intake on Concentration of Purine Derivatives in Urinary Spot Samples and Microbial Nitrogen Supply in Crossbred Bulls

  • George, S.K.;Dipu, M.T.;Mehra, U.R.;Verma, A.K.;Singh, P.
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권9호
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    • pp.1291-1297
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    • 2006
  • The potential of the spot urine sampling technique as an alternative to performing a total urine collection to predict the microbial nitrogen supply was evaluated in crossbred bulls. In a completely randomized design, 20 growing crossbred bulls were assigned four levels of feed intake (120, 100, 80 and 60% of voluntary dry matter intake) on diets comprised of wheat straw and concentrate mixture (50:50). After three months of experimental feeding, a metabolism trial was conducted for ten days, during which spot urine collections were performed every 6 h post feeding on days 9 and 10. The daily urinary excretion of allantoin (A) and purine derivatives (PD) decreased with the reduction in feed intake while creatinine (C) excretion remained similar in animals fed at different levels. The microbial nitrogen (MN) supply calculated from the PD excreted in total urine (35.08 to 72.08 g/d) was higher at increased levels of feed intake. PD concentration in spot urine samples had poor correlation with feed intake except at 12 h post feeding. A/C ratio and PD/C ratio in spot urine samples remained similar irrespective of sampling time and significantly (p<0.01) correlated with daily urinary PD excretion, digestible organic matter intake and dry matter (DM) intake. However, no significant differences were evident in these ratios among animals fed at levels 120, 100 and 80% of voluntary dry matter intake (VDMI) at different times post feeding. These results suggests that the spot urine sampling technique to predict the microbial protein supply is not suitable for detecting small differences in MN supply and hence, estimation of PD excreted in total urine (mmol/d) is necessary to assess precisely the MN supply in crossbred bulls.

Supplementation of Essential Oil Extracted from Citrus Peel to Animal Feeds Decreases Microbial Activity and Aflatoxin Contamination without Disrupting In vitro Ruminal Fermentation

  • Nam, I.S.;Garnsworthy, P.C.;Ahn, Jong Ho
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권11호
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    • pp.1617-1622
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    • 2006
  • Long-term storage of feeds or feedstuffs in high temperature and humid conditions can be difficult because of microbial contamination. Essential oil isolated from industrial waste citrus peel could be used as a preservative because it is likely to have anti-bacterial and anti-fungal activity. Our objective was to determine whether different levels (0.028, 0.056 and 0.112 g/kg) of citrus essential oil (CEO) would provide anti-microbial activity and enhance preservation of animal feed without influencing rumen fermentation. At 0.112 g/kg, CEO inhibited growth of Escherichia coli (ATCC 25922) and Salmonela enteritidis (IFO 3313). Growth of E. coli recovered after 24 h of incubation, but S. enteritidis continued to be inhibited for 72 h. Preservation of antibiotic-free diets for swine was assessed by observing anti-aflatoxin activity. Aflatoxin was detected in control feed samples on days 16 (8 ppb) and 21 (8 ppb) and in anti-fungal agent (AA) treated samples on days 16 (2 ppb) and 21 (4 ppb). However, aflatoxin was not detected in feed samples treated with CEO. Treatment with CEO and AA did not influence ruminal pH, dry matter digestibility (DMD) or organic matter digestibility (OMD) over 48 h of incubation in rumen fluid. Acetate and propionate were slightly higher with CEO treatment (p<0.05), but total concentration of volatile fatty acid (VFA) was not significantly affected by treatment. Ammonia-N concentration was slightly higher for the control treatment (p<0.05). This study showed that treating feed with CEO enhances preservation of animal feed without influencing in vitro rumen fermentation.

Using Varying Levels of Formic Acid to Limit Growth of Salmonella gallinarum in Contaminated Broiler Feed

  • Al-Natour, Mohammad Q.;Alshawabkeh, Khalil M.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권3호
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    • pp.390-395
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    • 2005
  • Reported here are the effects of added formic acid on inhibitory effect of Salmonella gallinarum in poultry feed. Two experiments were conducted to investigate the viability of S. gallinarum and pH of poultry feed using different dietary formic acid levels (0.0, 0.5, 1.0 and 1.5%) on inhibitory effect of S. gallinarum in broiler feed. Experiment one was conducted to investigate the viability of S. gallinarum and pH of artificially contaminated diet at 0, 1, 3, 5 and 7 days after treatment in vitro. Formic acid showed a significant (p<0.05) reduction in the viability for all treatments with time after treatment. Various formic acid levels in vitro showed a reduction in the pH of the diet depending upon the concentration of treated acid, and the diet remained acidic below the growth range of S. gallinarum. This meant that the bacterial cells were exposed to stressful conditions that made them unable to grow. Experiment two was conducted to find out the effect of dietary formic acid levels on S. gallinarum colonization and pH in the contents of crop, small intestine, large intestine and ceca and mortality rate of broiler chicks at 7, 14 and 21 days of age when fed artificially contaminated diet with S. gallinarum. The numbers of S. gallinarum re-isolated from all treated groups except in groups treated with 0.5% formic acid, decreased significantly (p<0.05) compared with the control group. The treatment significantly (p<0.05) lowered the pH of the crop, small intestine, large intestine and ceca contents in all groups except the groups treated with 0.5% formic acid compared with the control. All treated groups showed a significant (p<0.05) reduction in overall mortality rate during the experimental period (3 to 21 days) compared with the control. The results indicate that addition of formic acid in a total concentration of 1.5% to the diet of newly hatched broiler chicks significantly decreases the contamination of diet with S. gallinarum.

Effects of Early Feed Restriction on Growth, Fat Accumulation and Meat Composition in Unsexed Broiler Chickens

  • Santoso, U.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권11호
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    • pp.1585-1591
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    • 2001
  • The present study was conducted to evaluate the effect of early feed restriction on growth, fat accumulation and meat composition in unsexed broiler chickens. Five hundred 7-day old unsexed broiler chickens were distributed into ten treatment groups with 5 pens of 10 broilers each group. One group was fed ad libitum as the control group and other nine groups were fed 25% ad libitum for 3, 6 or 9 days, 50% ad libitum for 3, 6 or 9 days, and 75% ad libitum for 3, 6 or 9 days, respectively. Thereafter, they were fed ad libitum to 56 days of age. The present results showed that broilers showed compensatory growth when they were restrict-refed. Feed conversion ratio was significantly lower in broilers fed 25% ad libitum for 9 days (p<0.05). Triglyceride concentration of serum was significantly lower in restricted unsexed broilers (p <0.01), whereas cholesterol concentration was not significantly different. Abdominal fat was significantly lower in broilers fed 25% ad libitum for 9 days, 50% ad libitum for 3 days and 75% ad libitum for 6 or 9 days (p<0.05). Moisture and protein contents of meats were not significantly affected. Ash content of meat was significantly higher in restricted broilers. Fat content of meat was lower in broilers fed 25% ad libitum for 9 days, 75% ad libitum for 3 to 9 days. In conclusion, broilers showed compensatory growth when they were restrict-refed at an early age. In order to achieve the success of early feed restriction (namely reduce fat accumulation and improve feed conversion ratio with comparable body weight at market age), unsexed broilers should be fed at level of 25 ad libi=tum for 9 days starting at 7 days of age.

팽이버섯 탈병배지의 사료첨가가 육계의 질 및 생산비용에 미치는 영향 (Effect of the Adding of Flammulina velutipes Cultivation Media Wastes into Chicken Feed on the Meat Quality and Production Cost of Broiler)

  • 정종천;전창성;김승환;장갑열;박정식;나재천;전민현
    • 한국균학회지
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    • 제34권1호
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    • pp.29-33
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    • 2006
  • 버섯(mushroom)의 가축사료화 가능성을 조사하여 친환경농업 소재개발의 기초자료로 활용하고자 시험한 결과, 팽이버섯 탈병배지를 육게사료에 5~10% 첨가시 사료절감 10~20%, 복강지방 감소 25~37% 및 육질개선 효과가 있었다. 또한 팽이버섯 탈병배지를 육계사료에 5~10% 첨가하여 사육한 닭고기는 아미노산 함량이 33~38% 증가하였으나, 20% 이상 첨가시는 오히려 감소하는 경향이었다.