• Journal of Nutrition and Health
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• 제31권9호
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• pp.1404-1410
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• 1998

The purpose of this study was to investigate the effects of calcium intake levels on magnesium utilization in young and adult rats fed various levels of calcium(50, 100 or 200% of requirement) for 3 weeks. Feed intake, body weight gain, and feed efficiency ratios of the young group were significantly higher than those of the adult group. In calcium levels of tissues, serum calcium levels in young group were higher than in the adult group and kidney calcium levels in HCa(high-calcium group) were higher than in other groups. There was no significant difference in magnesium intake among age and diet groups. However, magnesium excretions through feces and urine in the adult group were higher than in the young group. Therefore, magnesium retention in the young group was higher than in the adult group. Especially in the young group, fecal magnesium excretion was increased with increasing levels of dietary calcium. Serum magnesium levels were lowest in YHCa(young 8t high-calcium) group, and there was no significant difference in liver and kidney levels among the calcium-diet groups. These results indicate that high calcium consumption promotes of fecal magnesium excretion and decreased magnesium retention rates in growing rats. Therefore, it is suggested that mineral interactions should be considered in the supplementation of dietary calcium intake for growth. (Korean J Nutrition 31(9) 1404-1410, 1998)

• Carbon letters
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• 제2권1호
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• pp.44-54
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• 2001

The characteristics of adsorption and desorption of benzene and toluene were investigated at a fixed bed packed with the activated carbon and activated carbon fiber. Through breakthrough experiments under various feed concentration conditions, it was found that the slope of mass transfer zone and the tailing in the breakthrough curves were different from the feed conditions due to different heats of adsorption. In hot nitrogen desorption, the regeneration time and mass transfer zone of the toluene desorption curve were longer than those of the benzene desorption curve because of the difference in adsorption affinity. With an increase in the regeneration temperature, the height of roll-up and the sharpness of desorption curves increased but the regeneration times decreased. The adsorption capacities of the activated carbon and activated carbon fiber after three-time thermal regenerations decreased about 25% and 37% for benzene and 18% and 25% for toluene, respectively. To investigate the effect of the regeneration temperature on the energetic efficiency, the characteristic desorption temperatures of toluene and benzene were investigated by calculating purge gas consumption and temperature.

• Asian-Australasian Journal of Animal Sciences
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• 제13권4호
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• pp.483-486
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• 2000

The influence of feed allowance on intake and nutrient utilization by Barbari goats given green maize (Zea mays) and potential feeding value of left-overs were studied. The goats were offered food at 3 levels to give left-overs of about 20% (T-1), 35% (T-2) and 50% (T-3) DM of offered amount. A marked effect of refusal rate on intake and digestibility of nutrients was found. The DMI, g/kg $W^{0.75}$ increased from 39.86 in T-1 to 50.91 and 66.55 g in groups T-2 and T-3, respectively. Allowing selective consumption at higher levels (T-2 and T-3), the intake of TDN and DCP from green maize was found not only to meet the maintenance requirement but provided surplus energy and protein for substantial production. The variability in diet selectivity between goats under different treatments was pronounced. As the level of food excess increased to T-3, the left overs had a higher IVDMD and crude protein and decreased cell wall constituents (p<0.05). Considering the substantial increase in intake and digestibility from feeding green maize at high allowances to goats, further studies are needed to develop practical feeding strategies.

• Asian-Australasian Journal of Animal Sciences
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• 제25권4호
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• pp.524-530
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• 2012

Laying hens were fed commercial diets added with supplemented fat (SFAT) at 0.6, 1.2, and 1.8% in order to study the long term dietary effects - on - their productive performance from 22 to 75 wk of age. Five hundred and seventy six Single Comb White Leghorn hens were assigned to one of the four dietary treatments. The experimental phase consisted of three periods of 18 wk each. The final body weight and gain of hens fed on diets with SFAT at 1.2% and 1.8% were lower (p<0.05) than those hens given no SFAT. The SFAT at the 1.2% and 1.8% levels improved egg production rate, egg weight and mass, as well as FCR. Mortality and feed consumption were not affected by dietary SFAT. Administration of a diet with SFAT significantly decreased the cracked-broken egg ratio (p<0.01). The beneficial effects of SFAT on egg production performance were particularly more pronounced at intermediate and later ages. Hence, SFAT by period interactions were significant for all traits studied except feed intake. Hens fed SFAT deposited significantly higher abdominal fat than those on the no-SFAT diet. As a result, SFAT at 1.2% and 1.8% inclusion levels provided benefits in terms of efficient table egg production.

• Asian-Australasian Journal of Animal Sciences
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• 제7권2호
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• pp.249-254
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• 1994

An experiment was conducted to investigate the performance and production cost of Pekin ducklings fed varying levels of dietary protein. One hundred and twenty ducklings in four separate groups received either 16, 18, 20 or 22% CP in the starter period (day-old to 3rd week of age). These four groups ate either 12, 14, 16 or 18% CP respectively during the grower-finisher period (4th week to 12th week of age). The results of the study indicated that in a tropical country like Bangladesh, the protein needs of Pekin ducklings should be satisfied depending on the age at which the birds are to be marketed. If the ducklings are to be marketed at 6 weeks, 22/18% CP would be sufficient. When the marketing is aimed at 9 weeks of age, 20/16% would be adequate. For ducklings which are to be marketed at 12 weeks of age, a protein level of 18/14% would be required. All these results should help the producers to keep production cost to a minimum. The exceptional capacity of ducklings for compensatory growth would help keep birds on low protein levels if they are reared upto 9 or 12 weeks before marketing.

• Journal of Nutrition and Health
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• 제28권4호
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• pp.309-320
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• 1995

The purpose of this research was to investigate the effect of calcium levels(50, 100 and 200% of requirement) on metabolism of Ca, Na and K in Young and adult female rats for 3 weeks. There was no significant difference in feed intake, body weight gain and feed efficiency ratio among the groups of different Ca intake level. Serum Na level of high-Ca group was significantly lower than that of low-Ca or normal-Ca group in Young rats. There was no significant difference in liver Ca and K contents among the groups of different Ca intake levels. But, Na content in liver was decreased by the increase of dietary Ca intake. Ca content in kidney of high-Ca group in young rats and normal-Ca group in adult rats were significantly higher than those of other groups. Na content in kidney of low-Ca group was lower than those of normal-Ca and high-Ca groups. Urinary excretions of Na and K and fecal excretion of Ca were increased by the increase of dietary Ca intake. But, fecal excretions of Na and K were not affected by dietary Ca intake. According to this study, it was found that the high Ca consumption promotes excretions of fecal Ca and urinary Na and K in rats. The study verifies the need for more study on the interrelationship among Ca, Na and K metabolism and bood pressure.

• 한국식품과학회지
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• 제3권2호
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• pp.110-116
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• 1971

50 및 100 Krad의 감마선을 조사한 미곡의 안전성을 실험할 목적으로 400 마리의 실험백쥐를 사용해서, 이 실험동물의 사료를 방사선 처리 사료구(LLTG, HLTG)와 비 방사선 처리 사료구(NCG, PCG)로 구분하고 7개월간 사육시키면서 이를 사료종류에 따르는 사료 섭취량 증체량, 사료효율 및 성장도를 측정하였다. 그 결과는 각 시험구(NCG, PCG, LLTG, HLTG)간에 있어서, 백쥐의 사료 섭취량, 증체량, 사료 효율 및 성장도의 변화가 통계적으로 유의차가 없었다.

• 한국가금학회지
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• 제10권1호
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• pp.30-34
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• 1983

브로일러 사료에 있어서 피혁분의 어분대치 가능성을 검토하기 위하여 브로일러용 초생추 (♀) 240수를 사용하여 6주간의 사양시험을 실시하였다. 양질의 어분과 대치한 피혁분의 사용수준은 0%, 1%, 2%, 4%, 6%이었으며 시험경과 얻어진 성적은 다음과 같다. 1. 본 시험에 사용된 피혁분의 단백질함량은 74.41%, 조회분함량 17.9%, 크롬함량 2.0%이었고 pepsin소화율은 85%이었다. 2. 증체량. 사료섭취량 및 사료효율은 피혁분 4%수준까지든 별 차이를 보이지 않았으나 6%수준에서는 현저히 (p＜0.05) 떨어지는 결과를 보였다. 이러한 결과는 브로일러 사료에서 피혁분을 어분과 대치하여 4%수준까지 사용가능함을 시사한다.

• 한국식품영양과학회지
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• 제17권2호
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• pp.103-109
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• 1988

Cholesterol의 주요한 대사산물인 중성steroids와 담즙산의 배설에 관한 내용은 cholesterol 대사를 이해하는데 있어 중요한 부분이다. 식이지방이 steroids의 배설에 미치는 효과에 대하여 아직 일치된 견해가 없어 본 실험에서는 식이지방의 수준(식이에너지의 15, 30 및 45% 과 P/S 비율(0.5 및 1.0)을 달리한 실험식이를 흰쥐에 4주간 급여하여 분변을 통한 총지질, 중성steroids 및 총담즙산배설에 미치는 영향을 조사하였다. 그 결과는 다음과 같다. 체중증가량, 식이섭취량 및 식이변전율은 cholesterol이 섭취되지 않은 경우나 섭취된 경우 모두 P/S 비율에 관계없이 식이지방의 수준에 유의적인 영향을 받았다. 지질소화율은 cholesterol이 섭취되지 않은 경우나 섭취된 경우 모두 P/S 비율에 관계없이 식이지방의 수준에 비례하여 유의적으로 증가하였다. 분변량, 총지질배설량, 중성steroids배설량과 그 조성 및 총담즙산배설량은 식이지방의 수준이나 P/S 비율에 따른 일관성 있는 영향을 나타내지 않았다. Cholesterol의 섭취는 체중증가량과 식이변전율을 유의적으로 향상시켰으며, 총지질배설량을 유의적으로 감소시켰고, 지질소화율을 증가시키고 경향을 나타내었다. 또한 중성 steroids배설량을 증가시키는 경향을 나타내면서, coprostanol의 조성비율을 감소시켰고 coprostanone의 조성비율을 증가시켰다. 반면에 총담즙산배설량은 감소시켰다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권2호
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• pp.198-203
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• 2008

This study was conducted to compare the effects of feeding high protein and low energy milk replacer (HPR; CP 25%, ME 3.6 Mcal/kg DM) with low protein and high energy milk replacer (HPR; CP 21%, ME 4.2 Mcal/kg DM) on feed consumption, body weight (BW) gain, health and selected blood metabolites in Holstein calves during the pre-weaning period. At each feeding, each milk replacer (MR) was prepared by mixing 0.125 kg of dry MR in 1L of warm ($60^{\circ}C$) water. The calves were fed either HPR (n = 10) or HER (n = 10) using mobile plastic bottles fitted with soft rubber nipples. All calves received 1.8L diluted MR at each feeding 3 times daily during the first 4 weeks of age; feeding frequency was reduced to 2 times daily for the next 2 weeks of age and then to once daily during the last week of the experiment. Jugular blood was sampled in calves at day 7, 14, 21, 35 and 49 of age to enumerate selected metabolites. Daily MR, starter and hay intake during the pre-weaning period were similar in calves fed HPR and HER. Consumption of starter, MGH and total DM steadily increased with the age of calves. Final BW, daily BW gain and feed efficiency of calves were not affected by treatments. Serum glucose, cholesterol, creatinine were decreased (p<0.05) and blood urea N was increased (p<0.05) in calves fed HER or HPR as they grew older. Serum glucose, total protein and albumin concentrations in calves were not affected by treatments. Serum GPT and GOT concentrations were higher (p<0.05) in calves on HPR than on HER. Scouring score, days scoured, respiratory score, rectal temperature and general appearance were similar in calves fed HPR and HER. Poor general appearance (dullness and droopy ears) of calves fed either HPR or HER reflected nutritional insufficiency and stress. In conclusion, energy and protein concentrations in MR did not affect feed intake and BW gain in Holstein calves during the pre-weaning period. Poor general appearance and lower BW gain of calves compared to those reported in the literature for milk fed calves prompt a demand for further research to improve the daily nutrient supply to MR-fed calves.