• Asian-Australasian Journal of Animal Sciences
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• 제6권2호
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• pp.235-242
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• 1993

In order to investigate the effects of dietary cellulose and protein levels on chick performance, four semi-purified diets were formulated so as to contain cellulose at levels of 5% (LC) and 20% (HC) in combination with 10% (LP) and 20% (HP) protein, and fed ad libitum to 1-week-old White Leghorn male chicks for 3 weeks. There were no significant differences in feed intake, body weight gain and feed efficiency between the LC-HP and HC-HP groups. All parameters were lower in the LP groups; the HC-LP group consumed very small amount of feed and lost body weight during the experiment. The retention rates of DM, ash, nitrogen and energy were higher in the HP than the LP groups. The triglyceride concentration of carcass was lower in the HC-LP group and that of liver was higher in the LC-LP group. The carcass total cholesterol level was higher in the HC-HP group. The relative weight of most digestive organs was higher in the HP group irrespective of the cellulose level. In conclusion, the chick performance was primarily influenced by dietary protein level, and when the chicks were fed inadequate levels of protein, the low cellulose level gave a better performance than the high cellulose level.

• Asian-Australasian Journal of Animal Sciences
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• 제33권11호
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• pp.1809-1816
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• 2020

Objective: This study was conducted to evaluate the effects of inclusion level and amino acid (AA) supplementation on energy values of soybean oil (SO) as determined by difference method or regression method when fed to growing pigs. Methods: Thirty-six barrows (initial body weight: 28.0±1.3 kg) were randomly assigned to one of 6 dietary treatments, which included 2 control diets formulated using a basal diet with or without AA supplementation, and 4 experimental diets with 5% or 10% SO addition in the 2 control diets, respectively. All pigs were individually housed in metabolism crates for 19 d, and during the last 5 d, total urine and feces production were collected. The nutrient digestibility in diets and the digestible energy (DE) and metabolizable energy (ME) values of SO were determined using the difference method and the regression method, respectively. Results: Our results showed that there were no interaction effects (p>0.05) between AA supplementation and SO inclusion levels on energy values of SO and dietary nutrient digestibility. The DE and ME values of SO determined by the difference method were not affected (p>0.05) by AA supplementation, however, the ME value of SO increased (p<0.05) as the inclusion level of SO increased. Moreover, the energy values of SO determined using the regression method were close to those determined using difference method with 10% SO inclusion, but were greater than those obtained using difference method with 5% SO inclusion. Conclusion: We concluded that the DE and ME values of SO increased with the inclusion level but were not affected by AA supplementation in the range of 0% to 10%. The difference method can substitute for the regression method to determine the DE and ME values of SO when the inclusion level is 10%, but not at 5% inclusion level.

• Asian-Australasian Journal of Animal Sciences
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• 제7권1호
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• pp.103-112
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• 1994

This study was a sequential experiment consisting if feeding trial and in vitro culture studies. Feeding was conducted by $2{\times}2{\times}2$ factorial design with two cimaterol levels (0, 0.25 mg/kg), two energy levels (3,200, 2,900 ME kcal/kg) and two sexes. In starting period (0-21 days) broilers were fed diets containing two energy level without dietary supplementation of cimaterol. During finishing period (21-42 days) cimaterol groups were fed cimaterol supplemented diets. In vitro cultures were carried out to study the cellular metabolism of protein and fat in liver and adipose tissues prepared from chicks used in feeding trials. Body weight gain was significantly improved by the administration of cimaterol to experimental diets by 2.4% (p < 0.05). Feed intake was reduced by cimaterol administration at the high energy level, but this trend was reversed at low energy level. Feed efficiency was improved by cimaterol administration and at high energy level the difference (5.7%) was significant(p < 0.05). The administration of cimaterol had no effects on percentage of abdominal fat content, giblet and neck. There was little difference in carcass yield between control and cimaterol treated group. The administration of cimaterol had no effects on nutrient metabolizability or carcass composition. The results of in vitro studies with liver tissues showed that cimaterol increased the lipolytic activities (p < 0.05) and decreased lipogenic activities (p < 0.05). In in vitro studies with acinar cell of liver tissues. cimaterol increased the amount of retained protein and decreased secreted protein at high energy level. but the trend was opposite at low energy level.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.732-736
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• 2008

The traditional method to calculate the gravity feed is to assume that only one tank in fuel system supplies the needed fuel to the engine, and then calculated for the single branch. Actually, all fuel tanks compete for supplying oil. Our method takes into consideration all fuel tanks and therefore, we believe, our method is intrinsically superior to traditional methods and is closer to understanding the real seriousness of the oil supply situation. Firstly, the thesis gives the mathematical model for fuel flow pipe, pump, check valve and the simulation model for fuel tank. On the basis of flow network theory and time difference method, we established a new calculation method for gravity feed oil of aeroplane fuel system, secondly. This model can solve the multiple-branch and transient process simulation of gravity feed oil. Finally, we give a numerical example for a certain type of aircraft, achieved the variations of oil level and flow mass per second of each oil tanks. In addition, we also obtained the variations of the oil pressure of the engine inlet, and predicted the maximum time that the aeroplane could fly safely under gravity feed. These variations show that our proposed method of calculations is satisfactory.

• Asian-Australasian Journal of Animal Sciences
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• 제31권11호
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• pp.1766-1772
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• 2018

Objective: This experiment was to investigate the effect of increasing levels of apparent metabolizable energy ($AME_n$) on the laying performance, egg quality, blood parameters, blood biochemistry, intestinal morphology, and apparent total tract digestibility (ATTD) of energy and nutrients in diets fed to laying hens. Methods: A total of three-hundred twenty 33-week-old Hy-Line Brown laying hens (Gallus domesticus) were evenly assigned to four experimental diets of 2,750, 2,850, 2,950, and 3,050 kcal $AME_n/kg$ in pens with floors covered with deep litter of rice hulls. There were four replicates of each treatment, each consisting of 20 birds in a pen. Results: $AME_n$ intake was increased (linear, p<0.05) with inclusion level of $AME_n$ in diets increased. Feed intake and feed conversion ratio were improved (linear, p<0.01), but hen-day egg production tended to be increased with an increasing level of $AME_n$ in diets. During the experiment, leukocyte concentration and blood biochemistry (total cholesterol, triglyceride, glucose, total protein, calcium, asparate aminotransferase, and alanine transferase were not influenced by increasing level of $AME_n$ in diets. Gross energy and ether extract were increased (linear, p<0.01) as the inclusion level of $AME_n$ in diets increased. Conclusion: Laying hens fed high $AME_n$ diet (i.e., 3,050 kcal/kg in the current experiment) tended to overconsume energy with a positive effect on feed intake, feed conversion ratio, nutrient digestibility, and intestinal morphology but not on egg production and egg mass.

• Asian-Australasian Journal of Animal Sciences
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• 제3권3호
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• pp.231-242
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• 1990

A study is reported which investigated the additive nature of digestible energy (DE) from dietary nutrients and to estimate the relative energy values of different energy-yielding nutrients in practical trout diets. A growth study was conducted over 12 weeks with 6 diets. Rainbow trout (Oncorhynchus mykiss) were fed diets once a day ad libitum. Digestible energy values determined and calculated had direct relationship indicating additive nature of such values for feed ingredients. Overall growth performance was best in a diet containing 33% digestible protein (DP) with a DP/DE ratio of 18.6. A reduction in digestible protein level with the same DP/DE rat io led to a significant decrease in growth and feed efficiency. The increase of 7% of lipid with concomitant decrease in protein resulted in the relative gain of 130% in growth and nutrient retention, suggesting that 1 g of lipid is equal to about 1.3 g of proteins in terms of net energetic value. Replacement of 10% of dietary lipid by carbohydrates led to a slight decrease in energy retention efficiency but to a great increase in lipid retention efficiency (130%) showing that dietary carbohydrates led to increased lipogenesis.

• Asian-Australasian Journal of Animal Sciences
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• 제20권3호
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• pp.440-452
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• 2007

The low feed intake immediately after weaning is responsible for villous atrophy and reduced growth rate in newly-weaned pigs. Overcoming this drawback will produce beneficial results for swine producers, and this warrants an understanding of the factors affecting the feed intake in newly-weaned pigs. In fact, a plethora of factors exert influences on feed intake in newly-weaned pigs, and these factors encompass health status, creep feeding, weaning age, mixing of litters, environment, dietary nutrient level and balance, palatability of ingredients, forms of diet presentation, water supply and quality, and stockmanship. Due to the complexity of the factors that affect the feed intake of weaned pigs, a comprehensive approach should be adopted to overcome the low feed intake problem right after weaning. It warrants mention that it is almost impossible to completely restore the feed intake just after weaning to pre-weaning level in terms of energy intake through dietary means which are available for being practiced economically and/or technically in current swine production. However, a refined dietary regime will certainly alleviate the low feed intake problem in the immediate postweaning period.

• 한국가금학회지
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• 제30권3호
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• pp.169-175
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• 2003

동절기에 산란피크 기간의 대부분이 해당되는 육용종계 산란기의 적정 에너지공급체계를 구명하기 위하여 강원도 홍천군 북방면 소재 홍천종계에서 케이지 사양형태의 로스 육용종계 400수를 공시하여 2002년 10월부터 2003년 7월까지 40주간(24∼64주령) 표 3과 같은 4가지 에너지공급체계로 사양시험을 실시한 결과를 요약하면 다음과 같다. 1) 총 산란율, 종란 산란율 및 평균난중은 전반적으로 처리간에 유의적인 차이가 인정되지 않았고, 55∼64주령의 산란후기에만 처리간에 유의적인 차이가 있었으나 에너지 공급수준에 따른 일정한 경향은 없었다. 2) 사료요구율과 ME 요구량 및 사료비는 모두 1일 에너지공급량이 많아질수록 증가하는 경향을 보였고(P<0.05), CP 요구량은 처리간에 유의적인 차이는 있었으나(P<0.05) 일정한 경향은 보이지 않았다. 결론적으로 1일 ME 공급량을 24주령에 280 kcal로부터 30∼34주령에 400 kcal까지 증가시키고 35주령 이후 380 kcal를 공급하여 전반적인 에너지공급량이 가장 적었던 Tl처리가 산란능력에 지장 없이 사료요구율과 ME요구량 및 사료비를 낮출 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권11호
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• pp.1652-1662
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• 2014

The present study investigated the optimum blending condition of protected fat, choline and yeast culture for lowering of rumen temperature. The Box Benken experimental design, a fractional factorial arrangement, and response surface methodology were employed. The optimum blending condition was determined using the rumen simulated in vitro fermentation. An additive formulated on the optimum condition contained 50% of protected fat, 25% of yeast culture, 5% of choline, 7% of organic zinc, 6.5% of cinnamon, and 6.5% of stevioside. The feed additive was supplemented at a rate of 0.1% of diet (orchard grass:concentrate, 3:7) and compared with a control which had no additive. The treatment resulted in lower volatile fatty acid (VFA) concentration and biogas than the control. To investigate the effect of the optimized additive and feed energy levels on rumen and rectal temperatures, four rumen cannulated Hanwoo (Korean native beef breed) steers were in a $4{\times}4$ Latin square design. Energy levels were varied to low and high by altering the ratio of forage to concentrate in diet: low energy (6:4) and high energy (4:6). The additive was added at a rate of 0.1% of the diet. The following parameters were measured; feed intake, rumen and rectal temperatures, ruminal pH and VFA concentration. This study was conducted in an environmentally controlled house with temperature set at $30^{\circ}C$ and relative humidity levels of 70%. Steers were housed individually in raised crates to facilitate collection of urine and feces. The adaptation period was for 14 days, 2 days for sampling and 7 days for resting the animals. The additive significantly reduced both rumen (p<0.01) and rectal temperatures (p<0.001) without depressed feed intake. There were interactions (p<0.01) between energy level and additive on ruminal temperature. Neither additive nor energy level had an effect on total VFA concentration. The additive however, significantly increased (p<0.01) propionate and subsequently had lower acetate:propionate (A/P) ratios than non-additive supplementation. High concentrate diets had significantly lower pH. Interactions between energy and additive were observed (p<0.01) in ammonia nitrogen production. Supplementation of diets with the additive resulted in lower rumen and rectal temperatures, hence the additive showed promise in alleviating undesirable effects of heat stress in cattle.

• Asian-Australasian Journal of Animal Sciences
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• 제32권12호
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• pp.1907-1913
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• 2019

Objective: Homoacetogens play important roles in the production of acetate in the large intestine of monogastric mammals. However, their diversity in the porcine large intestine is still unknown. Marker gene analysis was performed to assess the effects of energy level on the diversity and population densities of homoacetogens in porcine feces. Methods: Crossbred pigs were fed high or low energy-level diets. The high-intake (HI) diet was sufficient to allow a daily gain of 1.2 kg. The low-intake (LI) diet provided 0.6 times the amount of energy as the HI diet. Genetic diversity was analyzed using formyltetrahydrofolate synthetase gene (FHS) clone libraries derived from fecal DNA samples. FHS DNA copy numbers were quantified using real-time polymerase chain reaction. Results: A wide variety of FHS sequences was recovered from animals in both treatments. No differences in FHS clone libraries between the HI and LI groups were found. During the experimental period, no significant differences in the proportion of FHS copy numbers were observed between the two treatment groups. Conclusion: This is the first reported molecular diversity analysis using specific homoacetogen marker genes from the large intestines of pigs. There was no observable effect of feed intake on acetogen diversity.