• Asian-Australasian Journal of Animal Sciences
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• 제10권2호
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• pp.170-177
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• 1997

Two experiments were conducted to evaluate the effects of different extrusion conditions of corn and soybean meal on physico-chemical properties, ileal digestibility of amino acid and growth performance in weaned pigs. In Expt. 1, to compare physico-chemical properties and ileal digestibility of extruded corn and soybean meal, ground corn (2 mm screen) and soybean meal were separately extruded in four different conditions: (1) no preconditioning, low water supply (3.0 l/min) (NCLW), (2) no preconditioning, high water supply (7.0 l/min) (NCHW). (3) preconditioning (steam 3.0 l/min) with low water supply (3.0 l/min) (CLW), and (4) preconditioning (steam 3.0 l/min) plus high water supply (7.0 l/min) (CHW). Twenty-five cannulated pigs ($L{\times}Y{\times}D$, 7.62 kg BW for soybean meal, 8.80 kg BW for corn) were employed to determine nutrients digestibility of the extruded feedstuffs. In Expt. 2, a total of 90 pogs ($L{\times}Y{\times}D$, 9.18 kg BW) were used for a 28 d feeding trial to compare growth performance of pigs as affected by different extrusion conditions. Before mixing, corn and soybean meal were blended and extruded by the same conditions as described in Expt. 1. corn extruded with NCLW showed the highest (p < 0.05) degree of gelatinization (DG), compared to the lowest values observed for NCHW. Extrusion of corn with preconditioning (CLW and CHW) increased (p < 0.05) the DG as compared to the extrusion condition of NCHW. Extruded SBM with NCLW showed the lowest (p < 0.05) degree of texturization among treatments. The ileal digestibility of GE in SBM was higher with NCHW and CHW as compared to NCLW. The ileal digestibility of CP was lower in extruded corn, but was higher in extruded SBM, compared to untreated sample. Lysine digestibility of extruded corn (except corn with NCHW) was in general significantly improved. Extrusion of SBM resulted in no improvements in ileal digestibility of amino acids, but extruded SBM with NCLW had lower lysine digestibility compared to other treatments. In growth responses, pigs fed a diet with CLW had higher, but not significant, average daily gain (ADG) than other treatments during first 2 weeks. From d 15 to 28, pigs fed a diet with CHW had significantly less (p < 0.05) average daily feed intake (ADFI) than others except NCHW. In conclusion, the proper extrusion condition for corn and SBM in terms of ileal digestibility of amino acids and growth performance of weaning pigs seems to be the combination of preconditioning and a low water supply (3.0 l/min).

• Asian-Australasian Journal of Animal Sciences
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• 제20권11호
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• pp.1721-1728
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• 2007

An in vitro and a feeding trial were conducted to investigate the effect of xylanase supplementation on the feeding value of growing pig diets containing high proportions of Chinese double-low rapeseed meals (DLRM). Seven diets were formulated to meet NRC (1998) nutrient requirements. Diet 1 based on corn-soybean meal was used as positive control 1, and diet 2, a practical diet which incorporated a conventional level of Chinese DLRM (60 g/kg diet), as positive control 2. Diet 3 contained a higher level of DLRM (100 g/kg diet) as the negative control. Diet 3 plus xylanase at 0.10, 0.25, 0.50 and 0.70 g/kg diet created diets 4, 5, 6 and 7, respectively. The seven diets were incubated in triplicate with the in vitro two-stage enzyme incubation method to predict responses of diets to xylanase in terms of digestibility of dry matter (DM), crude protein (CP) and neutral detergent fibre (NDF). In vitro, the negative control had the lowest CP and NDF digestibility. Both DM and CP digestibility were increased (p<0.05) owing to xylanase supplementation either at 0.50 or 0.70 g/kg diet, and NDF digestibility was improved following xylanase addition at all of the test levels. There was a high linear correlation ($r^2>90$, p<0.05) between the activity concentration of the enzyme when transformed into its logarithmic value and in vitro digestibility coefficients of DM, CP or NDF. In the feeding trial, 112 crossbred pigs were randomly assigned to seven dietary treatments with 16 replicate pens of one pig each. An obvious dose effect on growth rate was observed ($r^2=0.79$, p<0.05) within the inclusion levels of xylanase. Compared with the negative control, xylanase addition at 0.70 g/kg diet resulted in significantly increased ADG (878 g/d vs. 828 g/d, p<0.05), and a tendency towards improved growth rate (868 g/d vs. 828 g/d, p = 0.10) was also observed following the inclusion of xylanase at 0.50 g/kg diet. It would appear that the nutrient utilization of corn and Chinese DLRM diets by pigs could be enhanced by an appropriate amount of xylanase addition. The in vitro and in vivo results suggested that the in vitro incubation method is feasible for predicting responses of pigs to exogenous enzymes and identifying those preparations that possess potential for improvement of the nutritive values of feedstuffs.

• Asian-Australasian Journal of Animal Sciences
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• 제25권9호
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• pp.1237-1247
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• 2012

The objective of this study was to evaluate the predictions of dry matter intake (DMI) and average daily gain (ADG) of Vietnamese Yellow (Vang) purebred and crossbred (Vang with Red Sindhi or Brahman) bulls fed under Vietnamese conditions using two levels of solution (1 and 2) of the large ruminant nutrition system (LRNS) model. Animal information and feed chemical characterization were obtained from five studies. The initial mean body weight (BW) of the animals was 186, with standard deviation ${\pm}33.2$ kg. Animals were fed ad libitum commonly available feedstuffs, including cassava powder, corn grain, Napier grass, rice straw and bran, and minerals and vitamins, for 50 to 80 d. Adequacy of the predictions was assessed with the Model Evaluation System using the root of mean square error of prediction (RMSEP), accuracy (Cb), coefficient of determination ($r^2$), and mean bias (MB). When all treatment means were used, both levels of solution predicted DMI similarly with low precision ($r^2$ of 0.389 and 0.45 for level 1 and 2, respectively) and medium accuracy (Cb of 0.827 and 0.859, respectively). The LRNS clearly over-predicted the intake of one study. When this study was removed from the comparison, the precision and accuracy considerably increased for the level 1 solution. Metabolisable protein was limiting ADG for more than 68% of the treatment averages. Both levels differed regarding precision and accuracy. While level 1 solution had the least MB compared with level 2 (0.058 and 0.159 kg/d, respectively), the precision was greater for level 2 than level 1 (0.89 and 0.70, respectively). The accuracy (Cb) was similar between level 1 and level 2 (p = 0.8997; 0.977 and 0.871, respectively). The RMSEP indicated that both levels were on average under-or over-predicted by about 190 g/d, suggesting that even though the accuracy (Cb) was greater for level 1 compared to level 2, both levels are likely to wrongly predict ADG by the same amount. Our analyses indicated that the level 1 solution can predict DMI reasonably well for this type of animal, but it was not entirely clear if animals consumed at their voluntary intake and/or if the roughness of the diet decreased DMI. A deficit of ruminally-undegradable protein and/or a lack of microbial protein may have limited the performance of these animals. Based on these evaluations, the LRNS level 1 solution may be an alternative to predict animal performance when, under specific circumstances, the fractional degradation rates of the carbohydrate and protein fractions are not known.

• Asian-Australasian Journal of Animal Sciences
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• 제27권11호
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• pp.1615-1622
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• 2014

An accurate assessment of moisture content in feed ingredients is important because moisture influences the nutritional evaluation of feedstuffs. The objective of this study was to evaluate various methods for moisture content determination. In Exp. 1, the weight loss on drying (LOD) of corn, soybean meal (SBM), distillers dried grains with solubles (DDGS), whey permeate, whey powder, spray-dried porcine plasma (SDPP), fish meal, and a mixed diet of these 7 ingredients were measured by oven drying at $135^{\circ}C$ for 2 h. Additionally, the samples were dried at $105^{\circ}C$ for 3, 6, 9, 12, or 15 h. The LOD contents of the DDGS, whey permeate, and whey powder measured by drying at $135^{\circ}C$ for 2 h were greater than the values measured by drying at $105^{\circ}C$ for 3 h (p<0.05). All samples except SDPP (p = 0.70) dried at $105^{\circ}C$ for 6, 9, 12, or 15 h caused more LOD compared with the samples dried for at $105^{\circ}C$ for 3 h (p<0.05). The LOD contents of the individual ingredients were additive when dried at $105^{\circ}C$ regardless of drying time. In Exp. 2, moisture contents of corn, SBM, wheat, whey permeate, whey powder, lactose, and 2 sources of DDGS (DDGS1 and DDGS2) were measured by the Karl Fischer method, oven drying at $135^{\circ}C$ for 2 h, and oven drying at $125^{\circ}C$, $115^{\circ}C$, $105^{\circ}C$, or $95^{\circ}C$ for increasing drying time from 1 to 24 h. Drying samples at $135^{\circ}C$ for 2 h resulted in higher moisture content in whey permeate (7.5% vs 3.0%), whey powder (7.7% vs 3.8%), DDGS1 (11.4% vs 7.5%), and DDGS2 (13.1% vs 8.8%) compared with the Karl Fischer method (p<0.05). Whey permeate and whey powder were considerably darkened as the drying time increased. In conclusion, drying samples at $135^{\circ}C$ for 2 h is not appropriate for determining the moisture content in whey permeate, whey powder, or DDGS as well as the mixed diet containing these ingredients. The oven-drying method at $105^{\circ}C$ for 5 to 6 h appears to be appropriate for whey permeate and whey powder, and at $105^{\circ}C$ for 2 to 3 h for DDGS.

• Asian-Australasian Journal of Animal Sciences
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• 제31권6호
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• pp.851-858
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• 2018

Objective: This study was conducted to compare different methods on effective energy evaluation of corn silage for beef cattle. Methods: Twenty Wandong bulls (Chinese indigenous yellow cattle) with initial body weight of $281{\pm}15.6kg$, were assigned to 1 of 5 dietary treatments with 4 animals per treatment in a randomized complete block design. Five dietary treatments included group 1 with corn silage only diet, group 2 with corn silage-concentrate basal diet (BD) and 3 groups with 3 test diets, which were the BD partly substituted by corn silage at 10%, 30%, and 60%. The total collection digestion trial was conducted for 5 d for each block after a 10-d adaptation period, and then an open-circuit respiratory cage was used to measure the gas exchange of each animal in a consecutive 4-d period. Results: The direct method-derived metabolizable energy and net energy of corn silage were 8.86 and 5.15 MJ/kg dry matter (DM), expressed as net energy requirement for maintenance and gain were 5.28 and 2.90 MJ/kg DM, respectively; the corresponding regression method-derived estimates were 8.96, 5.34, 5.37, and 2.98 MJ/kg DM, respectively. The direct method-derived estimates were not different (p>0.05) from those obtained using the regression method. Using substitution method, the nutrient apparent digestibility and effective energy values of corn silage varied with the increased corn silage substitution ratio (p<0.05). In addition, the corn silage estimates at the substitution ratio of 30% were similar to those estimated by direct and regression methods. Conclusion: In determining the energy value of corn silage using substitution method, there was a discrepancy between different substitution ratios, and the substitution ratio of 30% was more appropriate than 10% or 60% in the current study. The regression method based on multiple point substitution was more appropriate than single point substitution on energy evaluation of feedstuffs for beef cattle.

• Journal of Radiation Protection and Research
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• 제18권1호
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• pp.9-24
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• 1993

원자력발전소의 사고시 방사성물질의 단기간 침적 후 오염된 음식물에 의한 영향을 평가하기 위해 한국 환경에 적용이 가능한 동적 방사능영향 평가모델이 개발되었다. KORFOOD라 불리워지는 이 모델은 오염된 음식물의 섭취에 의한 누적선량뿐만 아니라 시간에 따른 선량을 평가하며, 또한 음식물내 시간에 따른 방사능농도의 변화를 해석한다. 설식경로에 중요한3가지 핵종과 13가지 음식물이 이 모델에서 고려되었다. 방사능농도의 동적변화는 침적, 풍화와 강우, 재부유, 뿐리흡취, 전이, 토양내 이동, 식물의 노화, 동물의 토양흥취 및 배설, 동물의 사료섭취와 배설 둥과 같은 여러 효과를 고려하여 모사되었다. 평가를 위한 입력 자료로는 침적되는 방사성물질의 양, 침적시점, 평가하고자하는 핵종 및 음식물의 종류가 요구된다. 고리지역 농작물자료를 사용하여 쌀에 대해 시간에 따른 비방사능농도와 고려되는 모든 음식물의 섭취에 따른 선량이 침적시점에 따라 계산되었다. 모델결과의 타당성 검증을 위해 이 분야에서 이미 공인받고 있는 독일모델 ECOSYS-87의 결과와 비교하였다. 비교결과, KORFOOD의 예측치가 ECOSYS-87의 예측값의 10배 범위내에 있어 좋은 일치를 보여주었다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.364-370
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• 2008

Chemical analysis and in vitro studies were conducted to investigate the nutritive value for ruminants of cell mass from lysine production (CMLP) which is a by-product of the lysine manufacturing process. Proximate analysis, protein fractionation, and in vitro protein degradation using protease from Streptomyces griseus and strained ruminal fluid were carried out to estimate ruminal protein degradability of CMLP with two reference feedstuffs-soybean meal (SBM) and fish meal (FM). Amino acid composition and pepsin-HCl degradability were also determined to evaluate postruminal availability. CMLP contained 67.8% crude protein with a major portion being soluble form (45.4% CP) which was composed of mainly ammonium nitrogen (81.8% soluble CP). The amount of nucleic acids was low (1.15% DM). The total amount of amino acids contained in CMLP was 40.60% DM, which was lower than SBM (47.69% DM) or FM (54.08% DM). CMLP was composed of mainly fraction A and fraction B2, while the protein fraction in SBM was mostly B2 and FM contained high proportions of B2 and B3 fractions. The proportion of B3 fraction, slowly degradable protein, in CP was the highest in fish meal (23.34%), followed by CMLP (7.68%) and SBM (1.46%). CMLP was degraded up to 51.40% at 18 h of incubation with Streptomyces protease, which was low compared to FM (55.23%) and SBM (83.01%). This may be due to the insoluble portion of CMLP protein being hardly degradable by the protease. The in vitro fermentation by strained ruminal fluid showed that the amount of soluble fraction was larger in CMLP (40.6%) than in SBM (17.8%). However, because the degradation rate constant of the potentially degradable fraction of CMLP (2.0%/h) was lower than that of SBM (5.8%/h), the effective ruminal protein degradability of CMLP (46.95%) was slightly lower than SBM (53.77%). Unavailable fraction in the rumen was higher in CMLP (34.0%) compared to SBM (8.8%). In vitro CP degradability of CMLP by pepsin was 80.37%, which was lower than SBM (94.42%) and FM (89.04%). The evaluation of protein degradability using different approaches indicated that soluble protein in CMLP may supply a large amount of ammonia in the rumen while insoluble protein can be by-passed from microbial attacks due to its low degradability. The results from this study suggest that CMLP can be used as a protein supplement to ruminants for supplying both non-protein nitrogen to rumen microbes and rumen undegradable protein to the host animal.

• 한국가금학회지
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• 제22권3호
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• pp.179-188
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• 1995

In Experiment 1, microbial assays were conducted on 57 feed ingredient samples to determine the content of total folic acid using Lactobacillus casei(ATCC 7469). Folic acid contents of feed samples pretreated with conjugase, ${\alpha}$-amylase, and a mixture of protease(Pronase)were corn, 09${\pm}$1.18($\pi$g${\pm}$SD); fish meal, 23.05${\pm}$1.27; milo, 29.34${\pm}$0.55; bakery meal, 25.80${\pm}$6.93; meat and bone meal, 56.76${\pm}$4.97; wheat middlings, 85.14${\pm}$2.56; and soybean meal, 193.97${\pm}$3.98. Experiments 2 and 3 were conducted to determine the effects of dietary supplemental folic acid and methionine on the performance of starting broiler chicks for 18 days. Four levels of dietary folic acid(0.24. 0.54,1.14 and 2.34mg/kg) and four levels of dietary methionine(0.45, 0.53,0.61, and 0.69%) were fed in a factorial design. The basal diet was based on corn, isolated soybean protein, meat and bone meal, and fish meal. It contained adequate amounts of all nutrients except methionine and folic acid in both experiments. Increased growth rate was observed in chicks fed the basal diet supplemented with either folic acid or methionine. Total dietary folic acid and methionine plus cysteine requirements for optimum growth were estimated to be 1.80 mg/kg and 0.89% in Experiment 2, and 1.47 mg/kg and 0.91% in Experiment 3, respectively. There were interactions between dietary folic acid and methionine on weight gain in both experiments. Chicks fed diets containing 2.34 mg folic acid /kg tended to display slow growth rate in both experiments. There was a significant linear feed conversion response to folic acid in Experiment 2, and a significant quadratic feed conversion resuonse to methionine in Experiment 3. There were both linear and quadratic liver folic acid responses to dietary folic acid in both experiments. There was no indication that dietary methionine had any effect on liver folic acid content. The incidence of tibial dyschondroplasia increased with increasing supplemental methionine, but were no significant differences detected at 5% level.

• Journal of Animal Science and Technology
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• 제45권2호
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• pp.241-250
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• 2003

국내산 고간류의 영양학적 평가는 매우 중요하다. 본 연구는 압력센서를 이용하여 국내산 고간류의 가스발생량과 반추위발효산물과의 상관관계를 비교하고자 실시하였다. 가스발생량 측정장치는 압력센서, AD board, LED 모니터 및 real-time graphics가 설치된 컴퓨터로 구성되었다. 가스발생량과 건물소화율은 지수방정식 Pt = a + b ($1-e^{-ct}$)을 기초로 추정하였다.초기 가스발생량은 볏짚이 가장 높았으며 보리짚, 밀짚순이었다. 시간당 분해상수는 3.8, 2.5, 2.5%$h^{－1}$로서 볏짚, 보리짚, 밀짚순이었다. 전체 휘발성 지방산은 초기 12시간에 유의한 차이가 있었지만 배양 72시간 이후의 농도는 세 처리구에서 비슷한 결과를 나타냈다. 가스발생량과 건물소화율의 상관지수($r^2$)는 0.76-0.83으로 밀접한 관계가 있었으며 또한 휘발성지방산과 가스발생량의 상관지수는 0.91-0.98로 매우 밀접한 관계가 있었다. 따라서 가스발생량, 건물소화율 및 휘발성 지방산의 단일상관관계는 고간류의 in vivo 소화율에서도 유사할 것으로 보인다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권3호
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• pp.356-364
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• 2009

The current ruminant feeding models require parameterization of the digestion kinetics of carbohydrate fractions in feed ingredients to estimate the supply of nutrients from a ration. Using an automated gas production technique, statistically welldefined digestion rate of carbohydrate, including soluble carbohydrate, can be estimated in a relatively easy way. In this study, the gas production during in vitro fermentation was measured and recorded by an automated gas production system to investigate degradation kinetics of carbohydrate fractions of a wide range of ruminant feeds: corn silage, rice straw, corn, soybean hull, soybean meal, and cell mass from lysine production (CMLP). The gas production from un-fractionated, ethanol insoluble residue and neutral detergent insoluble residue of the feed samples were obtained. The gas profiles of carbohydrate fractions on the basis of the carbohydrate scheme of the Cornell Net Carbohydrate and Protein System (A, B1, B2, B3 and C) were generated using a subtraction approach. After the gas profiles were plotted with time, a curve was fitted with a single-pool exponential equation with a discrete lag to obtain kinetic parameters that can be used as inputs for modern nutritional models. The fractional degradation rate constants (Kd) of corn silage were 11.6, 25.7, 14.8 and 0.8%/h for un-fractioned, A, B1 and B2 fractions, respectively. The values were statistically well estimated, assessed by high t-value (>12.9). The Kd of carbohydrate fractions in rice straw were 4.8, 21.1, 5.7 and 0.5%/h for un-fractioned, A, B1 and B2 fractions, respectively. Although the Kd of B2 fraction was poorly defined with a t-value of 4.4, the Kd of the other fractions showed tvalues higher than 21.9. The un-fractioned corn showed the highest Kd (18.2%/h) among the feeds tested, and the Kd of A plus B1 fraction was 18.7%/h. Soybean hull had a Kd of 6.0, 29.0, 3.8 and 13.8%/h for un-fractioned, A, B1 and B2, respectively. The large Kd of fraction B2 indicated that NDF in soybean hull was easily degradable. The t-values were higher than 20 except for the B1 fraction (5.7). The estimated Kd of soybean meal was 9.6, 24.3, 5.0%/h for un-fractioned, A and B1 fractions, respectively. A small amount of gas (5.6 ml at 48 ho of incubation) was produced from fermentation of CMLP which contained little carbohydrate. In summary, the automated gas production system was satisfactory for the estimation of well defined (t-value >12) kinetic parameters and Kd of soluble carbohydrate fractions of various feedstuffs that supply mainly carbohydrate. The subtraction approach, however, should be applied with caution for some concentrates, especially those which contain a high level of crude protein since nitrogen-containing compounds can interfere with gas production.