• Asian-Australasian Journal of Animal Sciences
• /
• 제31권10호
• /
• pp.1660-1669
• /
• 2018

Objective: This study was conducted to evaluate the effect of probiotics (Bacillus subtilis and Enterococcus faecium) and xylo-oligosaccharide (XOS) supplementation on growth performance, nutrient digestibility, serum profiles, intestinal health, fecal microbiota and noxious gas emission in weanling pigs. Methods: A total of 240 weanling pigs ([Yorkshire${\times}$Landrace]${\times}$Duroc) with an average body weight (BW) of $6.3{\pm}0.15kg$ were used in this 28-day trial. Pigs were randomly allocated in 1 of the following 4 dietary treatments in a $2{\times}2$ factorial arrangement with 2 levels of probiotics (0 and 500 mg/kg probiotics) and XOS (0 and 200 mg/kg XOS) based on the BW and sex. Results: Administration of probiotics or XOS improved average daily gain (p<0.05) during 0 to 14 d and the overall period, while pigs that were treated with XOS had a greater average daily gain and feed efficiency (p<0.05) compared with unsupplemented treatments throughout 15 to 28 d and the whole experiment. Either probiotics or XOS treatments increased the apparent total tract digestibility of nutrients (p<0.05) during 0 to 14 d. No effects on serum profiles were observed among treatments. The XOS increased villus height: crypt depth ratio in jejunum (p<0.05). The supplementation of probiotics (500 mg/kg) or XOS (200 mg/kg) alone improved the apparent total tract digestibility of dry matter, nitrogen and gross energy on d 14, the activity of trypsin and decreased fecal NH3 concentration (p<0.05). Administration of XOS decreased fecal Escherichia coli counts (p<0.05), while increased lactobacilli (p<0.05) on d 14. There was no interaction between dietary supplementation of probiotics and XOS. Conclusion: Inclusion of XOS at 200 mg/kg or probiotics (Bacillus subtilis and Enterococcus faecium) at 500 mg/kg in diets containing no antibiotics significantly improved the growth performance of weanling pigs. Once XOS is supplemented, further providing of probiotics is not needed since it exerts little additional effects.

• Asian-Australasian Journal of Animal Sciences
• /
• 제15권6호
• /
• pp.838-843
• /
• 2002

The objectives of this study were to examine growth performance and meat quality by three different feeding patterns in Korean native cattle (KNC). In each of 3 years, fifteen KNC were randomly assigned in a (3 feeding management)${\times}$(3 sex) factorial design experiment; thus, in total, there were 5 animals in each of the 9 treatments. The three feeding management treatments were longterm (24 month) restriction feeding (LTFR), long-term restriction feeding-hormone implant (LTFR-tH), and short-term (18 month) nonrestriction feeding (STFNR). Three sexes were bull, steer, and heifer. Concentrate diet was fed restriction-feeding method based on body weight in LTFR and LTFR-tH. However, the diet was fed ad libitum in STFNR. Hormonal implantation was made three times with M-$PO^{TM}$ for bulls and with F-$TO^{TM}$ for heifers at 18, 20, 22 month of age in LTFR-tH. Animal were purchased from the local cattle market and managed in two local farms and at the university research unit. Animals were slaughtered at 24 months for long-term trial and at 18 month for short-term trial. The growth rate was the highest in bulls and the lowest in heifers. However, the differences were diminished in F-$TO^{TM}$ implanted heifers. The average daily gain was high in STFNR due to ad libitum feeding. The carcass grade was similar among the treatments on percentage bases. Hormonal implants improved significantly the meat quality grade in all sexes. Castration increased body fat content and improved meat quality grade by intramuscular fat deposition. In conclusion, long-term feeding and hormone treatment increased meat quality grade more than short-term feeding. However, ADG was higher in the short-term trial although feedefficiency was lower.

• Asian-Australasian Journal of Animal Sciences
• /
• 제23권5호
• /
• pp.573-579
• /
• 2010

This study was conducted to determine the effects of different copper (inorganic and organic) and energy (tallow and glycerol) sources on growth performance, nutrient digestibility, gas emission, diarrhea incidence, and fecal copper concentration in growing pigs by using a 2${\times}$2 factorial design. In this trial, 96 pigs (63 d of age) were employed, with an average initial weight of 28.36${\pm}$1.14 kg. The dietary treatments were i) basal diet with 134 ppm copper (Korea recommendation) as $CuSO_4$+tallow; ii) basal diet with 134 ppm Cu as $CuSO_4$+glycerol; iii) basal diet with 134 ppm copper as CuMet+tallow; and iv) basal diet with 134 ppm copper as CuMet+ glycerol. Throughout the entire experimental period, no differences were noted among treatment groups with regard to the magnitude of improvement in ADG (average daily gain), ADFI (average daily feed intake) and G/F (gain:feed) ratios. The nitrogen (N) digestibility of pigs fed on diets containing organic copper was improved as compared with that observed in pigs fed on diets containing inorganic copper (p<0.05). An interaction of copper${\times}$energy was observed in the context of both nitrogen (p<0.05) and energy (p<0.01) digestibility. Ammonia emissions were significantly lower in the organic copper-added treatment groups than in the inorganic copperadded treatment groups (p<0.05). Mercaptan and hydrogen sulfide emissions were reduced via the addition of glycerol (p<0.05). No significant effects of copper or energy source, or their interaction, were observed in reference to diarrhea appearance and incidence throughout the entirety of the experimental period. The copper concentration in the feces was significantly lower in the organic copper source treatment group than was observed in the inorganic copper source treatment group (p<0.05). The results of this experiment show that organic copper substituted for inorganic copper in the diet results in a decreased fecal copper excretion, but exerts no effect on performance. The different energy (tallow and glycerol) sources interact with different copper sources and thus influence nutrient digestibility. Glycerol supplementation may reduce the concentrations of odorous sulfuric compounds with different Cu sources.

• Asian-Australasian Journal of Animal Sciences
• /
• 제30권10호
• /
• pp.1396-1404
• /
• 2017

Objective: This study was determined the influence of virginiamycin supplementation on growth-performance and characteristics of digestion of cattle with decreasing dietary net energy value of the diet for maintenance ($NE_m$) from 2.22 to 2.10 Mcal/kg. Methods: Eighty crossbred beef steers ($298.2{\pm}6.3kg$) were used in a 152-d performance evaluation consisting of a 28-d adaptation period followed by a 124-d growing-finishing period. During the 124-d period steers were fed either a lesser energy dense (LED, $2.10Mcal/kg\;NE_m$) or higher energy dense (HED, $2.22Mcal/kg\;NE_m$) diet. Diets were fed with or without 28 mg/kg (dry matter [DM] basis) virginiamycin in a $2{\times}2$ factorial arrangement. Four Holstein steers ($170.4{\pm}5.6kg$) with cannulas in the rumen (3.8 cm internal diameter) and proximal duodenum were used in $4{\times}4$ Latin square experiment to study treatment effects on characteristics of digestion. Results: Neither diet energy density nor virginiamycin affected average daily gain (p>0.10). As expected, dry matter intake and gain efficiency were greater (p<0.01) for LED- than for HED-fed steers. Virginiamycin did not affect estimated net energy value of the LED diet. Virginiamycin increased estimated NE of the HED diet. During daylight hours when the temperature humidity index averaged $81.3{\pm}2.7$, virginiamycin decreased (p<0.05) ruminal temperature. Virginiamycin did not influence (p>0.10) ruminal or total tract digestion. Ruminal (p = 0.02) and total tract digestion (p<0.01) of organic matter, and digestible energy (p<0.01) were greater for HED vs LED. Ruminal microbial efficiency was lower (p<0.01) for HED vs LED diets. Conclusion: The positive effect of virginiamycin on growth performance of cattle is due to increased efficiency of energy utilization, as effects of virginiamycin on characteristics of digestion were not appreciable. Under conditions of high ambient temperature virginiamycin may reduce body temperature.

• Asian-Australasian Journal of Animal Sciences
• /
• 제31권1호
• /
• pp.98-105
• /
• 2018

Objective: This study aimed to assess the effect of pelleted and expanded sorghum-based feeds prepared with different moisture levels and particle size of ingredients on metabolizable energy, ileal digestibility of amino acids and broiler performance. Methods: The experiment was performed with 720 male broiler chicks of the Cobb strain, with treatments of six replications, with 15 birds each; they were arranged in a completely randomized design and $2{\times}2{\times}2$ factorial scheme (pelleted or expanded feed processing, 0.8% or 1.6% moisture addition in the mixer, and particle size of 650 or 850 microns). Results: Higher pellet quality (pellets, % and pellet durability index [PDI]) was obtained in expanded diets and inclusion of 1.6% moisture. The particle size of 850 microns increased the PDI of final diet. All studied treatments had no significant effect on weight gain and broiler carcass and cut yields. Lower feed conversion occurred for birds fed pelleted feed at 42 d. The highest apparent metabolizable energy (AME) and apparent metabolizable energy corrected to zero nitrogen balance (AMEn) values of feed in the initial rearing phase (10 to 13 days) were observed in birds fed pelleted feed or for feed prepared with 1.6% moisture. The highest ileal digestibility coefficients of amino acids were obtained with the consumption of pelleted feed prepared with a particle size of 650 microns and 1.6% moisture. Conclusion: Pelleted feed prepared with a milling particle size of 650 microns and 1.6% moisture provided increased ileal digestibility of amino acids and AMEn in the starter period. However, the expanded feed improved pellet quality and feed conversion of broilers at 42 days of age. We conclude that factors such as moisture, particle size and processing affect the pellet quality, and therefore should be considered when attempting to optimize broiler performance.

• 한국수산과학회지
• /
• 제32권1호
• /
• pp.18-21
• /
• 1999

본 연구는 넙치 치어 (평균체중 1.6g)의 적정 사료 공급 횟수를 조사하여 경제적이고 수질오염원을 줄이기 위한 먹이 공급 체계를 제시하기 위해 수행되었다. 양어가들이 주로 사용하고 있는 건조 pellet 형태의 상품사료와 습사료 (moist pellet, MP)를 제조하여 각 실험수조 (50$\iota$)에 40마리씩 3 (diet)$\times$5 (feeding regimen)$\times$3 (replication) factorial design으로 수용하여 사육 실험 하였다. 사료 공급은 1일 4회 (06:00, 10:00, 14:00, 18:00), 1일 3회 (06:00, 12:00, 18:00), 1일 2회 (06:00, 18:00), 1일 1회 (06:00) 및 2일 1회 (09:00)로 설정하였다. 3 종류의 실험사료로 넙치 치어를 30일간 사육 실험한 결과, 모든 사료에서 공급 횟수가 낮아질수록 일일사료섭취량은 감소하였으며 (P<0.05),사료 공급 횟수가 동일할 때에도 사료 종류에 따라 사료 섭취량이 달라지는 경향을 보였고, 특히 MP 사료가 다른 두 사료보다 그 섭취량이 낮았다. 성장은 세 사료 모두 1일 3회 공급구는 1일 4회 공급구와 유의적인 차이가 없었으므로 1.6$\~$4g의 넙치 치어의 적정 사료 공급 횟수는 1일 3회가 적당할 것으로 판단된다. 따라서 사료를 불필요하게 자주 공급할 필요가 없을 것으로 보이며, 과다한 사료 공급은 경제적으로나 인력적인 면에서 불이익이 초래될 것으로 판단된다.

• 한국수산과학회지
• /
• 제48권1호
• /
• pp.96-103
• /
• 2015

The effects of $CO_2$ concentration, nutrient levels, and irradiance on the growth of germlings and juveniles, and on the photosynthesis of adults were examined in a green tide alga, Ulva australis. We used a factorial experimental design with two $CO_2$ concentrations (380 and 750 ppm), two nutrient levels (control and PES medium), and two irradiance levels (50 and $100{\mu}mol$ photons $m^{-2}s^{-1}$). Germlings grew best ($664.15{\pm}61.45{\mu}m$ in length) under conditions of 750 ppm, PES, and $100{\mu}mol$ photons $m^{-2}s^{-1}$ after 10 days in culture. Relative growth rates (RGR) of the juveniles were greatest (4.41% $day^{-1}$) under conditions of 750 ppm, PES, and $50{\mu}mol$ photons $m^{-2}s^{-1}$ after 5 days in culture. Photosynthetic efficiency ($F_v/F_m$) of the adult discs was $0.73{\pm}0.05$ before the experiment and reached a maximum ($0.83{\pm}0.01$) under conditions of 750 ppm, control, and $50{\mu}mol$ photons $m^{-2}s^{-1}$ after 5 days in culture. Growth (germlings and juveniles) and photosynthesis (adult discs) of Ulva australis increased when $CO_2$ levels were 750 ppm. Additionally, the optimal irradiance for growth and photosynthesis differed among stages, wherein germlings grew best at $100{\mu}mol$ photons $m^{-2}s^{-1}$, juveniles grew best at $50{\mu}mol$ photons $m^{-2}s^{-1}$, and adults photosynthesized most at $50{\mu}mol$ photons $m^{-2}s^{-1}$. The performance of Ulva australis at all examined life stages was enhanced under the PES nutrient treatment. In conclusion, the physiological responses of U. australis to varying $CO_2$, nutrient, and irradiance levels differed slightly among life stages. However, growth and photosynthesis always increased with elevated $CO_2$ and nutrient concentrations. These results indicate that U. australis green tide blooms might occur more frequently in coastal areas if $CO_2$ and nutrient concentrations increase.

• Asian-Australasian Journal of Animal Sciences
• /
• 제18권7호
• /
• pp.1029-1035
• /
• 2005

A 3${\times}$4 factorial field experiment with a complete randomised split-plot design with four replicates was conducted from June 2002 to March 2003 at the experimental farm of the Nong Lam University, Ho Chi Minh City, Vietnam, to determine effects of different harvesting heights (10, 30 and 50 cm above the ground) and cutting intervals (45, 60, 90 and 285 days) on yield of foliage and tubers, and chemical composition of the foliage. Cassava of the variety KM 94 grown in plots of 5 m${\times}$10 m at a planting distance of 30 cm${\times}$50 cm was hand-harvested according to respective treatments, starting 105 days after planting. Foliage from the control treatment (285 days) and all tubers were only harvested at the final harvest 285 days after planting. Dry matter and crude protein foliage yields increased in all treatments compared to the control. Mean foliage dry matter (DM) and crude protein (CP) yields were 4.57, 3.53, 2.49, and 0.64 tonnes DM $ha^{-1}$ and 939, 684, 495 and 123 kg CP $ha^{-1}$ with 45, 60, 90 and 285 day cutting intervals, respectively. At harvesting heights of 10, 30 and 50 cm the DM yields were 4.27, 3.67 and 2.65 tonnes $ha^{-1}$ and the CP yields were 810, 745 and 564 kg $ha^{-1}$, respectively. The leaf DM proportion was high, ranging from 47 to 65%. The proportion of leaf and petiole increased and the stem decreased with increasing harvesting heights and decreasing cutting intervals. Crude protein content in cassava foliage ranged from 17.7 to 22.6% and was affected by harvesting height and cutting interval. The ADF and NDF contents of foliage varied between 22.6 and 30.2%, and 34.2 and 41.2% of DM, respectively. The fresh tuber yield in the control treatment was 34.5 tonnes $ha^{-1}$. Cutting interval and harvesting height had significant negative effects on tuber yield. The most extreme effect was for the frequent foliage harvesting at 10 cm harvesting height, which reduced the tuber yield by 72%, while the 90 day cutting intervals and 50 cm harvesting height only reduced the yield by 7%. The mean fresh tuber yield decreased by 56, 45 and 27% in total when the foliage was harvested at 45, 60 and 90 day cutting intervals, respectively. It is concluded that the clear effects on quantity and quality of foliage and the effect on tuber yield allow alternative foliage harvesting principles depending on the need of fodder for animals, value of tubers and harvesting cost. An initial foliage harvest 105 days after planting and later harvests with 90 days intervals at 50 cm harvesting height increased the foliage DM and CP yield threefold, but showed only marginal negative effect on tuber yield.

• 대한환경공학회지
• /
• 제35권12호
• /
• pp.918-928
• /
• 2013

각 응집지로의 유입유량 불균등현상은 대부분 정수장에서 직면하고 있는 중요한 문제점이다. 이와 같은 유량의 불균등현상은 응집지 분배수로의 구조, 지별 유출위어의 높이차 등과 관계가 있으나, 시설물 구조개선에 의한 유량의 균등화는 투자비용 대비 실효성이 크지 않은 문제점이 있다. 본 연구의 목적은 정수 시설물의 개선 없이 실험계획법(DOE, Design Of Experiment)과 반응표면분석법(RSA, Response Surface Analysis)을 이용한 유입밸브 개도율의 최적화로 각 응집지로의 유입유량을 균등하게 하는 것이다. 병렬로 연결된 6개 응집지의 유입밸브 개도율(%)과 유량분배율(%)을 각각 특성치(Y)와 인자(X)로 선정하고, 실험계획법과 반응표면분석법을 적용하여 지별 유량 균등분배를 위한 지별 유입밸브 개도율의 최적화 및 회귀식을 산출하였다. 최적화된 지별 유입밸브 개도율의 현장 적용결과, 지별 유량분배율의 표준편차는 3.80%에서 0.42%, 지별 침전수탁도의 표준편차는 0.29 NTU에서 0.03 NTU로 각각 감소하였다.

• Journal of Biosystems Engineering
• /
• 제38권2호
• /
• pp.95-102
• /
• 2013

Purpose: Using a laboratory indented cylinder separator, broken rice separation experiments were conducted and the characteristics of the separation process were studied to provide information for developing a prototype indented cylinder broken rice separator. Methods: Rice (Ilmi variety) milled in a local RPC was used for the experiment. Rice kernels were classified into four groups according to their length l; whole kernels (I > 3.75 mm), semi-whole kernels (2.5 < I < 3.75 mm), broken kernels (1.75 < I < 2.5 mm), and foreign matters (I < 1.75 mm). A laboratory grain cleaner, Labofix '90 (Schmidt AG, Germany) was used for the experiments. Experiments were designed as a $4{\times}4$ factorial arrangement in randomized blocks with three replications. Cylinder rotational speeds (17, 34, 51, 68 rpm) and trough angles (15, 37.5, 60, $82.5^{\circ}$) were the two factors and feed rates (25, 50 kg/h), indent shapes (Us, $S_1$ type), and indent sizes (2.5, 3.75 mm) were treated as the blocks. Two 125 g samples and one 125 g sample were taken at the cylinder outlet and from the trough, respectively. The whole, semi-whole, and broken kernel weight ratio of the samples and feed was determined by a rice sizing device. From these weight ratios, purities, degrees of extraction and coefficient of separation efficiency were calculated. Results: Trough angle, cylinder speed, and their interaction on the coefficient of separation efficiency were statistically significant. Cylinder speed of 17, 34, and 51 rpm made the most effective separation when the trough angle was $15^{\circ}$ or $37.5^{\circ}$, $60^{\circ}$, and $82.5^{\circ}$, respectively. Maximum values of coefficient of separation efficiency were in the range of 60 to 70% except when the indent size was 2.5 mm and were recorded for the combinations of low cylinder speed (17 rpm) with medium trough angle ($37.5^{\circ}$ or $60^{\circ}$). Indent shape did not appear to make any noticeable difference in separation efficiency. Conclusions: Due to the interaction effect, the trough angle needs to be increased appropriately when an increase in cylinder speed is made if a rapid drop of effectiveness of separation should be avoided. In commercial applications, $S_1$ type indents are preferred because of their better manufacturability and easier maintenance. For successful separation of broken kernels, the indent size should be set slightly bigger than the actual sizes of broken kernels: an indent size of 3.0 mm for separating broken kernels shorter than 2.5 mm.