• Asian-Australasian Journal of Animal Sciences
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• 제6권3호
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• pp.451-461
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• 1993

Four hundred and eighty broiler chicks of both sexes were obtained from commercial hatchery (Hubbard) and raised on floor pens. All chicks were allowed free access to food from 0 to 7 and 20 to 56 days of age. At 7 days of age, all broilers were weighed individually, and divided into five groups as follows: 1. feed ad libitum as the control; 2. allowed free access to food 3 days and starved 1 day ($3{\times}1$); 3. allowed free access to food 2 days and starved 1 day ($2{\times}1$); 4. allowed free access to food 1 day and starved 1 days ($1{\times}1$) and; 5. allowed free access to food 2 days and starved 2 days ($2{\times}2$). Broilers were restricted for 12 days (d 7 through 17) of a 56-day trial. Broilers were fed a commercial starter diet (crude protein 23.8% and ME 3,070 kcal/kg) for 21 days, and commercial finisher diet (crude protein 20% and ME 3,160 kcal/kg) from 22 to 56 days of age. Although there was compensatory growth in some groups, (the $1{\times}1$ female group, and the $3{\times}1$ and $2{\times}1$ male grous), its level was not sufficient to achieve normal body weight at market age. There was sexual dimorphism for accelerated growth as well as differences in the ability to achieve a complete compensation of growth to the weight, feed conversion ratio, and body composition of ad libitum chicks. Early feed restriction could be used to reduce production cost because of the lower fed conversion ratio, mortality rate and the amount of starter diet consumed by broilers. The response of chicks to early feed restriction might depend on the degree of feed restriction, the method of feed restriction, duration of feed restriction, and sexes.

• Asian-Australasian Journal of Animal Sciences
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• 제6권3호
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• pp.401-410
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• 1993

Day-old male and female broilers obtained from commercial strain (Hubbard) were used in this study. At 7 days of age, all chicks were weighed individually (female 0.11 kg and male 0.12 kg in average) and divided into 5 group of 45 birds each group with no replicate in each treatment group as follows: 1. fed ad libitum; 2. fed 75% ad libitum; 3. fed 65% ad libitum; 4. fed 55% ad libitum; 5. fed 45% ad libitum. Chicks were restricted for 10 days (d 7 through 17) of a 56-day trial. Chicks were fed a commercial starter diet (crude protein (CP) 23.8% and metabolizable energy (ME) 3,070 kcal/kg) for 21 days, and commercial finisher diet (CP 20% and ME 3,160 kcal/kg) from 22 to 56 days of age. When chicks were feed-restricted at an early age, compensatory growth did not immediately occur following refeeding. Body weights of restricted chicks were not equal to the ad libitum chicks before 49 days of age. At 56 dyas of age, body weights of restricted chicks were heavier (p<0.01). Abdominal fat values of female chicks fed ad libitum was not significantly different from those fed 45% to 75% ad libitum. Carcass fat values of restricted female chicks were lower than those of control chicks when female chicks were fed either 55% or 45% ad libitum. Furthermore, feed efficiencies of restricted chicks were better. The response of chicks to early feed restriction might depend on the degree of feed restriction, and sex. Factors contributing carcass fat included energy loss, fat protein ratio of carcass, fatty acid synthesis in the liver and triglyceride content of the liver. The heavier body weights in the restricted chicks might be correlated with the lower growth rate during period of feed restriction.

• Applied Microscopy
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• 제20권1호
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• pp.90-104
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• 1990

This study was carried out to investigate the ultrastructural changes of the proximal epiphyseal plate of the femur in young chickens that had been treated with monosodium glutamate(MSG). Eighty 1-day old broiler chickens(Hubbard strain) were divided into control and experimental groups. The experimental group received daily administration of MSG(3mg/g of body weight in 0.75% saline) per orally for 1, 3, 6, 9, 12, 15, 18 and 21 days, and were sacrificed with exanguination. The control group received an equal volume of 0.75% saline. For the transmission electron microscopy, the prehypertrophic cartilage zone of epiphyseal plate was cleaved, fixed with 2% glutaraldehyde(containing 0.2% ruthenium red), postfixed with 1 % osmium tetroxide, embedded in Epon 812, and stained with uranyl acetate and lead citrate. For the scanning electron microscopy, the calcified zone of epiphyseal plate was cleaved and coated with gold palladium. The results obtained were as follows; 1. On transmission electron microscopic examination, the sacculation decreased from 12 day to 21 day MSG administrated groups, and the vesiculation decreased in 18 and 21 day MSG administrated groups in rough endoplasmic reticulum of chondrocytes in prehypertrophic cartilage zone. The ruthenium red binding particles in pericellular rim, territorial matrix and interterritorial matrix increased from 9 day to 21 day MSG administrated groups, but the crystalloid materials decreased. 2. On scanning electron microscopic examination, the trabecular formation and calcospherites of calcification zone decreased in 18 and 21 day MSG administrated groups. The resorption cavities widened from 15 day to 21 day MSG administrated groups.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1994년도 추계학술대회논문집; 한국종합전시장, 18 Nov. 1994
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• pp.116-120
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• 1994

최근 항공우주 및 생산자동화 분야의 급격한 발달에 따라 정밀도와 효율성을 향상시키기 위해 저중량, 고강도 구조물이 요구된다. 그러나 경량화 추세로 인해 수반되는 구조물의 유연성 증가로 외력에 대한 구조응답의 진폭이 커지고 구조물의 피로 수명이 단축되어 매우 위험한 상황에 이를 수 있다. 이런 바람직하지 않은 진동현상을 제어하기 위해 여러 제어이론을 응용한 진동억제시스템의 연구가 활발하며, 신소재인 압전재료의 개발로 새로운 방향이 제시되고 있다. 압전재료는 유연한 구조물에 부착되어 압전재료의 수축, 팽창 운동에 의해 발생된 에너지를 부착된 구조물에서의 제어력으로 사용되어, 진동 혹은 자세 및 형상 제어에 활용되고 있다. 압전재료에 대한 연구로는 Crawley, de Luis3가 보의 표면 혹은 내부에 압전세라믹을 부착하여 액튜에이터로 사용하는 경우 집중모멘트를 가하는 역할을 함을 밝혔고, Hanagud, obal은 압전재료를 센서와 액튜에이터로 사용해 복합재료 보에 대한 최적 진동제어 알고리즘을 개발, 그 성능에 대한 효과를 조사하였고 임의의 위치에 부착된 센서 및 액튜에이터를 고려한 복합재료 보의 운동방정식을 유한요소법을 이용 유도하였으며 변위율 피드백(rate feedback)과 모달피드백(modal feedback) 제어기를 적용하여 진동제어 효과를 고찰하였다. 그리고 Tomas, James, Hubbard는 압전필름을 액튜에이터로 사용해 복합재료 보에 Liapunov 제어기와 변위율 피드백 제어기를 사용하여 능동감쇠기를 설계하였고, Lee, Chaing, Sullivan은 압전필름을 센서와 액튜에이터로 사용해 평판에 변위율 피드백 제어기를 적용한 능동감쇠기를 설계하고 실험적으로 수행하였다. Base가 백색잡음가진을 지속적으로 받을 때 보끝의 움직임이 최소가 되도록 제어하고자 연구를 수행 중인 바 그 결과로소 본 논문에서는 적용시켰고 F-P-K 방정식을 이용해 확률영역으로 변환하여 LQR 제어기와 pole allocation 제어기를 시스템에 적용시켜 우수한 특성을 갖음을 제어 시뮬레이션의 결과를 통해 입증하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권6호
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• pp.873-879
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• 2003

The study was conducted to improve the nutritive value of defatted rice polishing (DRP). DRP was treated with various concentrations of HCl, NaOH, $H_2O_2$ and Kemzyme-H $F^{(R)} and the effect on its chemical composition and nutritive value in broiler chicks was observed. The treatments levels of 0.4 N HCl, 0.2 N NaOH and 6% $H_2O_2$ were selected from many concentrations of HCl, NaOH and $H_2O_2$ tried earlier on DRP. The selection was made on the basis of release of nutrients from DRP. The Kemzyme-H $F^{(R)} was used at rate of 0.1% of DRP. The selected concentrations of HCl, NaOH, and $H_2O_2$ were then used for treatment of DRP that was used in biological experiments. Two hundred and forty, day-old Hubbard male broiler chicks (38-40 g) were randomly divided into 48 experimental units with five chicks each. Each chemically treated DRP was incorporated into broiler diets at 10, 20 or 30% levels replacing yellow corn from the control feed and thus sixteen experimental feeds were prepared. These feeds were randomly assigned to 48 experimental units such that there were three replicates of chicks on each diet. The results of the study suggest that DRP can be effectively used in broiler diets at 20% level. The best weight gain and feed conversion ratio were observed with diet containing 20% level of DRP treated with 6% $H_2O_2$. The diets containing 30% levels of treated DRP were uneconomical, as excess use of oil was required to compensate the energy needs of the birds.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.454-460
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• 2002

While atherosclerosis is a major killer, there is now concern that mortality from the disease will increase due to the rising incidence of type II diabetes. Because diet can potentially influence both diseases, it is important to elucidate the role of diet in the progression of atherosclerosis. In addition, the mechanisms involved in dietary-related alterations of the disease need to be defined to guide public health recommendations to reduce athero-sclerosis incidence and limiting unwanted side effects. Since diet is thought to play a role in atherosclerosis even without added complications due to type II diabetes, reducing the incidence of that metabolic disease will not be enough. While evidence is increasing that high intake of carbohydrate can lead to type II diabetes and atherosclerosis, the preponderance of existing evidence indicates that intake of specific fats as a major dietary causal factor. It has recently been hypothesized that a dietary fat link to atherosclerosis may depend partly on the activity of a transcriptional regulator, the peroxisome proliferator activated receptors (PPAR). Thusfar, PPAR $\alpha$, $\beta$/$\delta$ and ${\gamma}$, have been shown to play a major role in metabolism, inflammation, and cancer. Furthermore, PPAR may regulate specific processes associated with atherosclerosis such as triglyceride and low density lipoprotein (LDL) metabolism; the reverse cholesterol transport pathway; lipid accumulation within plaques; the local inflammatory response and plaque stability. Synthetic ligands for PPAR have been developed; however, natural ligands include specific fatty acids and their metabolites. Though the role of PPAR in atherosclerosis has been reported with respect to synthetic ligands, additional studies need to be done with established and possible natural ligands. In this review, we will focus on the relation of dietary fat to PPAR alteration of atherosclerosis.

• 한국가금학회지
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• 제33권2호
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• pp.165-169
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• 2006

The objective of this study was to elucidate the basis for the difference in sperm production of broiler breeders. Nine sexually mature Hubbard broiler breeder males, 35 weeks of age, were trained for two weeks for semen collection on alternate days by abdominal massage technique. Following the training, the breeder males were collected daily for five successive days. The males were then classified as low or high sperm producers. The mean body weights of individual males were also recorded on the basis of body weight at the start and end of the experiment. Immediately after last collection the males were slaughtered and testes biometry was determined. Daily sperm output of individual males varied from $0.21{\times}10^9\;to\;2.64{\times}10^9$ sperm. The daily sperm production of low sperm producer males was lower ($0.47{\pm}0.13\;vs.\;2.06{\pm}0.20{\times}10^9$; P<0.05) than high sperm producer males. Testes weight of low sperm producer males was lower ($6.32{\pm}1.6\;vs.\;20.33{\pm}4.76\;gm$; P<0.05) than high sperm producer males. Moreover the testis weight of high sperm producer males was 3.22 times higher than low sperm producer males. The average body weight of high sperm producer males was higher ($4,389{\pm}116.3\;vs.\;3,960{\pm}131.77\;gm$; P>0.05) than low sperm producer males. The correlation coefficients indicate significantly positive correlation of body weight (P<0.05) and testes weight (P<0.01) on semen volume, sperm concentration and daily sperm production.

• Asian-Australasian Journal of Animal Sciences
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• 제15권8호
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• pp.1170-1177
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• 2002

An experiment was conducted to assess the interaction between genotypes and dietary lysine content in commercial broiler chicks by measuring growth, and response to sheep red blood cells (SRBC) and Escherichia coli (E.coli) inoculation. Female chicks from four genotypes (A=Anak 2000; B=Hubbard; C=Cobb and D=Synthetic broiler) were fed four levels of lysine in diet from d old till the end of experiment. The lysine content of the diet was 9.61, 10.51, 11.41 and 12.31 g/kg. Body weights at 0, 14, 28 and 42 d of age and pen-wise feed intake till 14, 28 and 42 d of age were recorded. Production of antibody against SRBC and resistance to E.coli were measured at 5 d of post inoculation (PI) at 43 d of age. Also, response to phytohemaglutinin-P (PHA-P) was measured at 12 and 24 h of PI at 48 d of age. Genotype by dietary lysine interaction was significant for body weights at 14 and 28 d of age, but not at 42 d of age. Genotype by dietary lysine interaction was not significant for feed efficiency, for antibody titers against SRBC, and for air sac lesion score, relative bodyweight change, and relative weights of bursa and spleen in response to E.coli inoculation. However, a significant interaction was observed between the levels of lysine and dosage of SRBC for antibody titers. There was significant genotype by dietary lysine interaction for cutaneous basophilic hypersensitivity (CBH) response to PHA-P at 12 and 24 h of PI. It may be concluded that to obtain optimum body weight and immunity in commercial broilers the dietary lysine requirement may be recommended specific to the genotype.

• Asian-Australasian Journal of Animal Sciences
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• 제19권3호
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• pp.418-424
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• 2006

This experiment was conducted to explore the efficacy of lacquer (Rhus verniciflua) supplementation on growth performance, nutrient digestibility, carcass traits and serum biochemical values in commercial broilers. Eight hundred and forty Hubbard broiler chicks (1d old) were randomly distributed and allotted to four dietary treatments for five weeks. Each treatment had 5 replicates with 42 birds each. The dietary treatments were (1) control (2) 1% lacquer, (3) 2% lacquer and 4) 4% lacquer supplied as meal in the diet. Supplementation with lacquer improved weight gain (p = 0.0960) showing a linear trend during the starter phase (0-3 wk), but weight gain, feed intake and feed conversion ratio remained unaffected at the finisher phase (4-5 wk) and overall (0-5 wk). The nutrient digestibility studies conducted after 18 and 35 days of experimental feeding showed a linear (p<0.05) increase in digestibility of CP and ether extract at both measurement timess. The carcass studies were conducted on two birds per replicate (10 per treatment) at the end of both 3 and 5 wk. The dressing percentage, liver weight, heart weight, abdominal fat and the breast meat expressed as a percentage of live weight, did not differ significantly due to treatments at both phases. The serum cholesterol and high-density lipoprotein (HDL) showed a linear decrease (p = 0.0683 and p = 0.0322, respectively) as the level of supplementation increased at 3 wk; at 5 wk serum cholesterol, HDL and triglyceride levels decreased significantly showing a positive linear effect of lacquer on fat metabolism. The meat color values such as lightness, redness and yellowness did not reveal any significant trend. Overall, it could be concluded that lacquer supplementation at higher levels did not affect growth performance, but had a positive impact on fat metabolism by influencing fat digestibility and reducing serum cholesterol and triglyceride.

• Asian-Australasian Journal of Animal Sciences
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• 제21권11호
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• pp.1629-1634
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• 2008

A trial was conducted to determine the effect of low crude protein (CP) diets with constant metabolizable energy to crude protein (ME:CP) ratio on growth, body composition and nutrient utilization of broiler chicks from 1 to 26 days of age. Four dietary treatments having four levels of CP and ME as 23, 22, 21 and 20% and 3,036, 2,904, 2,772 and 2,640 kcal/kg, respectively, were formulated and a ME:CP ratio of 132 was maintained in all the diets. Digestible lysine was maintained at 1.10 of the diet. A total of 1,760 day-old Hubbard broiler chicks were randomly divided into 16 experimental units and each diet was offered to four experimental units at random. Feed intake was increased (p<0.05) while weight gain and feed conversion ratio were adversely affected (p<0.05) when the diets with low CP and ME were fed to broilers. Total protein intake and total ME intake were linearly decreased (p<0.05) and protein efficiency ratio and energy efficiency ratio were lower (p<0.05) than in the chicks fed dietary regimen with 22% CP and 2,904 kcal/kg ME. The whole body analysis of the birds revealed that chicks fed the lowest dietary regimens retained less (p<0.05) nitrogen and more ether extract than chicks fed the control diet, however, body dry matter, total body ash and fat free body protein were not affected. Similarly, protein and energy utilization were also unaffected by the dietary treatments. In summary, chicks fed low CP diets with constant ME:CP ratio grew slower, used feed less efficiently and retained less protein and more body fat than chicks fed the control diet.