• Asian-Australasian Journal of Animal Sciences
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• 제15권9호
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• pp.1319-1325
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• 2002

Two experiments were conducted to evaluate the effect of early feed restriction on growth, feed conversion ratio (FCR) and mortality in unsexed broiler chickens. In Experiment 1, 350 one-day-old broiler chickens were divided into 7 groups. Each treatment group was represented by five replicates of ten broilers each. One group was fed ad libitum as the control group and the other six groups were fed 25% ad libitum (25% multiplied by amount of feed intake of ad libitum chickens at the previous day) for 4 or 6 days, 50% ad libitum for 4 or 6 days, and 75% ad libitum for 4 or 6 days. In experiment 2, 500 broiler chickens were divided into 10 groups. Each treatment group was represented by five replicates of ten broilers each. One group was fed ad libitum as the control group. Three ages of feed restriction initial timing (2, 4 or 6 days of age) and three types of feed restriction (physical restriction, meal feeding and diet dilution) were used ($3{\times}3$) in both experiments. They were feed-restricted for 6 days. Results showed that restricted broilers exhibited compensatory growth in both experiments except for diet dilution groups. In both experiments, FCR of restricted broilers was higher, whereas feed intake of them was lower during restriction period. FCR of restricted broilers was lower upon refeeding. Mortality was inconsistently affected by early feed restriction. Leg abnormality was lower in restricted broilers in both experiments. Level of feed restriction significantly influenced body weight, FCR and feed intake of restricted broilers (p<0.05), but duration of feed restriction had no effect. Type of restriction significantly affected body weight, feed intake and FCR (p<0.05). It appeared that to achieve the best result (complete compensatory growth and better FCR), broilers should be restricted at 25% ad libitum for 6 days (Experiment 1). Meal feeding started at 2 days of age would show the best performance (Experiment 2).

• 한국축산식품학회지
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• 제24권2호
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• pp.202-208
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• 2004

이 총설은 출하 전 절식에 관한 문헌을 요약 정리한 것이다. 도축 시 도체 오염 방지는 효과적인 절식 프로그램을 실시할 때만이 가능하다. 특별히 법으로 외견 또는 미생물적 오염을 규제하는 나라의 경우 절식은 매우 중요하다. 육계에 대한 절식은 도축 시 장 내용물로부터 도체 오염을 줄일 수 있어 이를 권장하고 있다. 대부분의 연구가 적정한 절식 시간, 도축, 가공의 효율성 유지 및 닭고기 안전성을 확보하기 위한 수단으로서의 절식 효과에 대해 초점을 두고 진행되었다. 실제적인 절식 프로그램은 생축생산 능력과 사육방식, 도축방법, 도축검사 및 도축관련 규정이 달라 나라마다 다르다는 점을 지적한다.

• 한국축산식품학회지
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• 제39권2호
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• pp.276-285
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• 2019

The objective of this study was to determine effects of humic acid (HA) and blueberry leaf powder (BLP) supplementation in pig feed on productivity, blood profiles, and meat quality characteristics of longissimus muscle. The experimental design included six treatments: 1) CON, no addition; 2) T1, BLP 0.1%; 3) T2, BLP 0.2%; 4) T3, humic acid 2%; 5) T4: humic acid 2%+BLP 0.1%; and 6) T5: humic acid 2%+BLP 0.2%. HA and BLP supplementation in pig feed significantly increased average daily feed intake (ADFI) values (p<0.05). HA supplementation in pig feed had beneficial effects in lipid profiles without altering feed efficiency rate (FER). HA and BLP co-supplementation in pig feed decreased pH in longissimus thoracis (p<0.05). In addition, sensory characteristics were enhanced when pig feed was supplemented with HA and BLP without causing adverse effects in meat quality. Taken together, addition of HA and BLP in pig feed may produce functional meat products.

• 한국수산과학회지
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• 제42권3호
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• pp.262-267
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• 2009

Two 15-week feeding trials were conducted to investigate feeding rate and feeding frequency for growth of sub-adult flounder in suboptimal water temperature ($12^{\circ}C$). In the first experiment, duplicated groups of fish (initial mean weight of 279 g) were fed a extruded pellet once a day at the different feeding rates of 0.1, 0.15, 0.2, 0.3% body weight per day (BW/d), and satiation (0.32% BW/d). Weight gain and feed efficiency were increased significantly (P<0.05) with increase in feeding rates from 0.1 to 0.3% BW/d, but there were no significant differences in weight gain and feed efficiency of fish fed the diet between 0.3% BW/d and to satiation. Crude protein content of dorsal muscle of fish fed the 0.1% BW/d diet was significantly (P<0.05) lower than that of the other groups. In the second experiment, duplicated groups of fish (initial mean weight of 281 g) were fed to apparent satiation with a extruded pellet at three different feeding frequencies (one meal every two days, one meal a day and two meals a day). Weight gain, feed efficiency and condition factor of fish fed one meal every two days were significantly (P<0.05) lower than those of fish fed one meal and two meals a day, but there were no significant differences in weight gain, feed efficiency and condition factor of fish fed between one meal and two meals a day. Based on the results of this study, optimum feeding frequency is one meal a day with satiation feeding for growth and feed efficiency of sub-adult flounder (270-350 g) in suboptimal water temperature ($12^{\circ}C$).

• 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.

• 한국가금학회지
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• 제30권1호
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• pp.49-54
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• 2003

본 연구는 눈꽃 동충하초(Paecilomyces japonica)의 접종사료 급여가 육계의 증체량, 사료효율 및 닭고기 중에 전이되는 cordycepin의 함량에 미치는 영향을 구명하기 위하여 실시하였다. 120마리의 초생추를 기초사료만 급여한 대조구, Paecilo-myces japonica 접종사료 5% 대체한 T1, 접종사료 10% 대체한 T2및 접종사료 20% 대체한 T3의 4 처리구로 구분하여 2∼5주령간(4주 동안) 사양실험을 진행하였다. 눈꽃 동충하초가 접종된 사료 중의 cordycepin의 함량은 미접종 사료보다 유의하게 높았다(P<0.05). 증체량 및 사료효율은 사육 전기에 T1 구에서 현저하게 개선되었지만(P<0.05),사육 후기에는 T3 처리구에서 가장 낮게 평가되었으며(P<0.05), 사육전 기간에 증체량 및 사료효율은 T3구가 다른 처리구보다 낮아지는 경향을 보였다 사양시험 종료 후, 가슴살과 대퇴부살 중에 검출된 코디세핀(Cordycepin)의 함량은 동충하초 처리구에서 대조구보다 통계적으로 높았지만(P<0.05).동충 하초 처리구간에 cordycepin 함량은 차이가 없었다. 본 연구결과로 증체량 및 사료효율은 눈꽃동충하초 접종사료 5% 대체구(T1)에서 개선되는 경향을 보였으며, 가슴살 및 대퇴부살에서 코디세핀(Cordycepin)의 함량은 눈꽃동충하초 접종사료의 급여로 높게 나타났다(P<0.05).

• 소성∙가공
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• 제24권4호
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• pp.272-279
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• 2015

The characteristics of the laser metal deposition parameters were studied to enhance the deposition efficiency using a diode pumped disk laser. STD61 hot tool steel plate and Fe based AISI M2 alloy were used as a substrate and powder for the laser metal deposition, respectively. Among the laser metal deposition parameters the laser power, track pitch and powder feed rate were used to estimate the deposition efficiency. From the experimental results, the deposition efficiency was shown to be excellent when 1.8kW laser power 500um track pitch and 10g/min of the powder feed rate were used. For this optimal condition the average hardness of the deposition track was approximately 830HV, and this value is 30~50% better than the hardness of the commercially produced tool steel after heat treatment.

• International Journal of Industrial Entomology and Biomaterials
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• 제11권1호
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• pp.1-12
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• 2005

Feed conversion efficiency contributes directly or indirectly on the cost benefit ratio of silkworm rearing and is considered to be an important physiological criterion for evaluating the superiority of silkworm breeds/hybrids. Food intake, assimilation and conversion of indigenous as well as exotic silkworm races are well studied by many researchers. In this review, an attempt has been made to consolidate works on feed conversion aspects of indigenous and exotic silkworm races. The paper also deals with the effect of various factors viz., nutritional, environmental and feeding on food assimilation and conversion parameters of mulberry silkworm.

• Asian-Australasian Journal of Animal Sciences
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• 제4권4호
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• pp.361-368
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• 1991

In two experiments 640 starcross replacement pullets between 25 and 154 days of age were fed ad libitum on either of 16 diets formed by the combination of $4CP{\times}4ME$ levels to study the interaction of CP and ME on growth performances. In both experiments, feed intake decreased, but protein intake, energy intake, live weight gain and feed conversion efficiency increased and sexual maturity hastened with the increase of dietary protein and/or energy level. The protein conversion efficiency decreased with the increase of dietary protein level. The energy conversion efficiency, however, did not show any relationship with dietary energy level. There was a greater improvement of growth performance due to simultaneous increase of dietary protein and energy level than that of increasing protein or energy alone.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1994년도 추계학술대회 논문집
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• pp.98-102
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• 1994

There are many difficulties in automatic polishing for die & mold surfaces. Even though the process has been studied in the past 15 years, it has not been achieved yet, but by the process of actual hand work of well-skilled workers. A new magentic assisted polishing process, which is one of the potential method for automation of surface finishing has been studied in the past 10 years by colleagues. The process has many merits, but on the other hand also has demerits, one being low efficiency of gridability by comparision with grinding wheel polish. Therefore, some attempts were tried to improve the grindability by adopting electropolishing, ultra-high speed milling, 5-axis controlled machine etc... most recently by collegues. This study also aims to improve the efficiency of polishing by introducing the easily-polished shape surface milling method equalizing the tool feed per tooth to the pick feed. This milling method was experimentally confirmed to have sufficient grindability to polish milled surface (with 10 .mu. mRmax surface roughness) into mirror surface (with 0.4 .mu. mRmax surface roughness).