• Journal of Microbiology and Biotechnology
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• 제25권2호
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• pp.185-195
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• 2015

Glucoamylase is an important industrial enzyme. Glucoamylase production by industrial Aspergillus niger strain featured with two major problems: (i) empirical substrate feeding methods deteriorating the fermentation performance; and (ii) the high raw materials cost limiting the economics of the glucoamylase product with delegated specification. In this study, we first proposed a novel three-stage varied-rate substrate feeding strategy for efficient glucoamylase production in a 5 L bioreactor using the standard feeding medium, by comparing the changing patterns of the important physiological parameters such as DO, OUR, RQ, etc., when using different substrate feeding strategies. With this strategy, the glucoamylase activity and productivity reached higher levels of 11,000 U/ml and 84.6 U/ml/h, respectively. The performance enhancement in this case was beneficial from the following results: DO and OUR could be controlled at the higher levels (30%, 43.83 mmol/l/h), while RQ was maintained at a stable/lower level of 0.60 simultaneously throughout the fed-batch phase. Based on this three-stage varied-rate substrate feeding strategy, we further evaluated the economics of using alternative carbon sources, attempting to reduce the raw materials cost. The results revealed that cornstarch hydrolysate could be considered as the best carbon source to replace the standard and expensive feeding medium. In this case, the production cost of the glucoamylase with delegated specification (5,000 U/ml) could be saved by more than 61% while the product quality be ensured simultaneously. The proposed strategy showed application potential in improving the economics of industrial glucoamylase production.

• Asian-Australasian Journal of Animal Sciences
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• 제1권4호
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• pp.223-232
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• 1988

Fifty-two wether lambs weighing 30 kg were randomly assigned to 5 treatment groups; 1) initial slaughter. 2) control-maintenance (CON-MT), 3) control-ad libitum (CON-AL), 4) cimaterol-maintenance (CIM-MT) and 5) cimaterol-ad libitum (CIM-AL). Ad libitum-fed animals had free access of a high-concentrate diet, whereas maintenance animals were restricted in feed intake to maintain the initial weight of 30 kg for 90 days. Cimaterol was administered in the feed at 10 mg/kg. Regardless of feeding level, the administration of CIM improved carcass weight (p < .05), dressing % (p < .01), longissimus muscle area (p < .01), leg conformation and muscling (p < .01), USDA yield and quality grades (p < .01) and protein concentration (p < .01) in carcass as well as in muscle. Cimaterol feeding decreased organ wt (p < .01), baekfat depth (p < .01), intramuscular fat and overall fatness. Cimaterol was effective for muscle accretion even under restricted feeding condition. The greater accretion of muscle was the result of the hypertrophy of both type I and type II muscle fibers but the hypertrophy of type II fiber (110%) was much greater than that of type I fiber (37%). Cimaterol feeding decreased muscle DNA concentrations but the number of nuclei per muscle fiber was not changed, indicating that the lower DNA concentration was due to the dilution effect caused by the hypertrophy of muscle fiber. As evidenced by lower flank streaking, lower marbling and darker muscle, CIM feeding adversely affected meat quality. Meat tenderness was also adversely affected, resulting in significantly (p H .01) tougher meat in CIM-fed animals.

• 대한지역사회영양학회지
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• 제3권1호
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• pp.3-11
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• 1998

This study was aimed to evaluate any influence of environmental factors associated with feeding on infants' growth. One hundred infants(62 males and 38 females) aged 4-9 months were measured for length and were weighed. Their mothers were interviewed using questionnaires including general and environmental characteristics and maternal feeding attitude, ideal body habitus, infant's food behavior, and infant's food behavior, and infant's temperament. A further study was conducted on 29 infants at the time their ages reached 12 months. Their dietary intakes were assessed, and blood hemoglobin and serum ferritin concentrations were measured. Z-scores of weight-for-age(WAZ) and Z-scores of height-for-age(HAZ) of 4-9 month- old infants were not correlated with age, education level, income, weight, and height of their parents. Formula-fed infants had significantly lower WAZ and body mass index (BMI) than those of breast fed infants. WAZ was significantly correlated with maternal feeding attitude, but not with ideal body habitus, infant's food behavior or infant's temperament. WAZ of 12-months after birth because of supplementary foods introduced from 6 months of age. WAZ and BMI were positively correlated with blood hemoglobin concentration. Therefore, to ensure proper growth of infants, efforts should be given to postental factors such as breast-feeding, maternal feeding attitude, adequate iron status as well as prenatal factors. (Korean J Community Nutrition 3(1) : 3∼11, 1998)

• 한국초지조사료학회지
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• 제38권3호
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• pp.165-169
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• 2018

The main objective of this experiment was to investigate effects of two different feeding systems on body weight, milk yield, milk composition, and mineral and fatty acids content of Holstein dairy cows' milk. Sixteen of 25 months-old Holstein dairy cows were assigned to two groups (n=8) to study effects of the feeding system for 150 days. Two feeding systems were compared for five months; Group 1 was housed indoors and mainly fed a concentrate diet, Group 2 was maintained outdoors for five-seven hours/day on various kinds grass in a pasture. The experiment was conducted June-October 2017. Results revealed the indoor-fed cows had higher body weight, that was significant compared with the outdoor-based feeding system of Holstein dairy cows (p<0.05). Indoor-raised milking cows had higher milk yield (32.45 kg) as compared with pasture-raised milk yield (26.44 kg). Cows fed indoors significantly increased milk yield, total protein content, lactose, citric acid level, and lowered level of total solid and free fatty acids relative to the pasture-fed milking cows (p>0.05). There were higher levels of mineral content and fatty acid content in the milk of indoor-fed dairy cows than the pasture-raised dairy cows (p>0.05). Our study results demonstrated the potential benefits of the indoor feeding system for increased body weight, milk yield, mineral and fatty acids content summer through autumn when low pasture growth rates and quality may otherwise limit production.

• Journal of Animal Science and Technology
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• 제48권2호
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• pp.247-254
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• 2006

본 연구는 보리의 급여수준이 한우수소의 성장과 육질에 미치는 효과를 조사하고자 실시되었다. 수송아지 20두(평균체중 99㎏)를 공시하여 한우수소의 육성비육 시 보리의 급여수준(육성기－비육전기－비육후기 보리 배합비; 0-0-40, FⅡ40; 0-0-60, FⅡ60; 0-20-40, F2040; 0-20-60, F2040)이 증체와 육질에 미치는 효과를 구명하였다. 시험기간 동안의 체중은 성장단계별 보리 급여수준 간 차이는 보이지 않았으나, FⅡ40구의 24개월령 체중이 591.5kg으로 606.2～614.6kg 내외의 다른 처리구에 비해 다소 감소된 경향이었다. 그러나 FⅡ60구는 비육후기에 보리 60% 첨가된 사료를 섭취하면서 증체가 개선되는 경향이 있었다(P<.19). 한우수소에 대한 보리위주 사료의 급여는 생체중, 도체중과 도체율, 정육률, 거래정육률 그리고 KPH 지방과 뼈의 비율 등의 도체특성에 있어 처리 간 차이는 없었으나, 보리를 비육전기에 20%, 비육후기에 60% 급여한 F2060구의 한우수소에서 정육률과 지방률이 각각 89.82, 20.28%로 다른 처리구에 비해 다소 높았으며, 이로 인해 거래정육률은 최대 5.5% 가량 낮게 나타났다. 근내지방도는 FⅡ40구 및 F2060구에서 각각 3.75, 3.60으로 다른 처리구에 비해 높은 편이었으며, 조직감 역시 FⅡ60구와 F2060구가 공히 1.6으로 다른 두 처리구에 비해 양호하였다.

• Fisheries and Aquatic Sciences
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• 제18권3호
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• pp.265-271
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• 2015

A feeding trial of four dietary protein levels (20, 30, 40, and 50%) and two lipid levels (7 and 14%) with a factorial design was conducted to determine the optimal dietary protein and lipid levels for juvenile Israeli carp Cyprinus carpio. Triplicate groups of fish (average body weight, $1.3{\pm}0.02g$) were fed the experimental diets for 9 weeks. Survival of fish was not affected by either dietary protein or dietary lipid level. Weight gain and feed efficiency increased as dietary protein levels increased up to 40 and 50%, respectively. Weight gain was higher in fish fed the high-lipid diets with 20 and 40% protein content. Feeding efficiency increased as the dietary lipid level increased for the 30, 40, and 50% protein diets. Daily feed intake decreased with increasing protein level and the minimum feed consumption was observed in fish fed the 50% protein diet with 14% lipid content. Moisture and lipid contents of the whole body were affected by both dietary protein and lipid levels. The crude lipid content of fish fed the 14% lipid diet was higher than that of fish fed the 7% lipid diet at each protein level. The results of this study indicate that a diet containing 40% protein with 14% lipid content is optimal for the growth and effective protein utilization of juvenile Israeli carp.

• Asian-Australasian Journal of Animal Sciences
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• 제17권2호
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• pp.221-227
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• 2004

Nutrient utilization and plasma level of minerals were studied in lactating crossbred cows fed diet supplemented from different source of minerals. Twelve crossbred cows of first to third lactation during their mid stage of lactation were distributed equally under two groups and were fed concentrate mixture, green fodder (para grass) and finger millet straw as per requirement. Cows in group I were fed concentrate mixture supplemented with 1% mineral mixture whereas cows in group II were not supplemented with mineral mixture in the concentrate mixture but were offered additional quantity of green fodder (1 kg DM/cow/day) to compensate for the requirement of minerals. Balance study conducted towards the end of 120 days of feeding experiment indicated that the total dry matter intake in both the groups did not differ significantly. The cows in group II offered additional quantity of green fodder consumed significantly (p<0.05) more of green fodder (5.11 vs. 4.51 kg /animal/day) and the cows in group I consumed significantly (p<0.01) more of finger millet straw (1.71 vs. 0.92 kg/animal/day). The digestibility of major nutrients did not differ between the groups except for ether extract which was significantly (p<0.05) lower in cows fed additional green fodder. The total daily intake of P, Cu, Fe and Co did not differ significantly in both the groups whereas significantly higher intakes of Ca, Mg, Zn and Mn were observed in cows supplemented with inorganic source of minerals. However, supplementation through both the sources could meet the mineral requirement in group I and group II. The gut absorption (%) of all the minerals was comparable between the groups except for Mg which was significantly (p<0.05) higher in cows supplemented mineral mixture. The net retention of all the minerals was significantly more in the group supplemented with inorganic source of minerals. Except for P, Mg and Co the retention as percentage of total intake was comparable for all minerals in both the groups. Irrespective of source of mineral supplementation the average monthly blood plasma mineral levels (Ca, P, Mg, Cu, Zn, Fe) were within the normal range and comparable between the groups. Lower level of Cu observed at the start of the experimental feeding in both the groups increased with the advancement of supplemental feeding. The plasma Zn and Fe content in cows of both the groups did not vary. The blood plasma level of some minerals (Ca, P, Mg and Cu) was significantly higher towards the end of experimental feeding as compared to the initial values due to the reduction in milk yield with advancement of lactation or due to supplemental effect of minerals. It could be concluded that supplementation of minerals through inorganic source is better utilized in terms of retention as compared to green fodder (para grass), which is a moderate source of most nutrients.

• 수산해양기술연구
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• 제14권2호
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• pp.57-62
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• 1978

漁類의 食餌音, 游泳音 또는 低周波의 純音을 水中에 放音하여 漁類를 誘集하는데 成功하였다는 報告는 最近에 많이 發表되고 있다. 반대로 天敵이 내는 소리, 人工的으로 내는 소리의 剌戟으로 漁類의 驅集劾果을 내기 위한 연구는 희소하다. 末廣(1960)는 고기를 묵적한 장소에 쫓아 보내기 위해 대나무 장대로 水面을 두들겨서 고기를 그물속으로 쫓아 넣을 수 있다고 보고 했다. 또 寶際 韓國의 權現網漁業에서 2集의 網船이 曳網하여 曳網終期가 되면 날개부분에 있는 멸치는 자루쪽으로 후려넣기 위하여 漁艇에서 뱃삼, 드럼통, 꽹과리 등을 두들긴다. 저자는 본 실험에서 이것을 驅集劾果를 測定하여 보다 劾果的인 方法을 糾明하기 위하여 이들 소리의 音源에서 1m 떨어진 거리에서 指示騷音計로 音歷準位를 測定하면서 하고 그 錄音된 소리를 水中擴聲器를 통하여 無響水糟속의 멸치에게 放음했으며, 이들 소리가 명치를 驅集하는데 어느 정도 有效한가를 알기 위하여 멸치의 反應을 調査하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제11권2호
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• pp.107-116
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• 1998

Measurement of DCP is considered inadequate and unsatisfactory means of assessing the protein value of the diet as no distinction is made between the digestion in ferestomach and in the small intestine. Protein meals should be classified on the basis of rumen degradable protein (RDP) and rumen undegradable protein (UDP). Usually, protein meals naturally available with high level of UDP or bypass protein value should be preferred for incorporation in the diet of lactating and growing animals. However, if such resources are non-available or are expensive, protein meals having high degradability can be carefully subjected to heat or formaldehyde treatment to achieve desired level of rumen bypassability. Various studies conducted the world over have revealed that bypass protein feeding to ruminants, especially when animals are fed on crop residue based basal diet, help increasing feed conversion efficiency in growing and lactating ruminants.

• Asian-Australasian Journal of Animal Sciences
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• 제14권7호
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• pp.974-978
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• 2001

The effect of three varying ratios (high, medium and low) of Rumen Degradable Protein (RDP) to Undegradable Dietary Protein (UDP) of 37:63, 52:48 and 70:30 in iso-nitrogenous and iso-caloric concentrate mixtures on rumen fermentation profile was studied using rumen fistulated Jersey crossbred cows. Rumen pH and ammonia nitrogen concentration were found to be lower with a concentrate mixture containing a higher UDP level of 63.38% when compared with those having medium and low UDP levels of 47.55 and 29.75%, respectively, at all post feeding intervals. Total volatile fatty acid concentration as well as concentrations of individual fatty acids viz., acetate, propionate and butyrate were also found higher in animals fed concentrate mixture with the highest UDP level.