• 한국환경농학회지
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• 제17권3호
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• pp.189-194
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• 1998

토양반응이 산성이고 붕소함량이 낮은 사양질 밭에서 토양개량제로 석탄회와 석고, 패각을 석탄회80, 패각4, 석탄회56+석고24, 석탄회40+석고24+패각0.8ton/㏊ 수준으로 시용하고 가을배추 재배에 이어서 2년차 봄배추를 재배하여 배추생육과 품질에 대한 시용잔효를 검토하였다. 개량제 시용에 따른 배추의 수확물은 대조구의 8.7ton/㏊을 기준으로 석탄회+석고+패각 혼용구에서 834%, 석탄회+석고 혼용구에서 786%, 석탄회 단용구에서 755%, 패각 단용구에서 193% 증가하였다. 수확된 배추체내 환원당과 비타민-C, 전질소 함량은 처리별 수량 성적 경향과 일치하였고 조섬유는 반대경향을 보였다. 또한 석탄회가 시용된 구에서는 개량제 무시용구 및 패각단용구를 달리 붕소결핍증이 없었고 유해 중금속의 식물체 잔류량이 감소되거나 자연함량 이하였다. 그리고, 이들 토양개량제를 상용할 경우에는 작물의 균형있는 양분흡수를 위해 3요소비료와 함께 마그네슘을 별도 시용하는 것이 바람직할 것으로 생각되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권8호
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• pp.1022-1027
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• 2010

Effects of increasing dietary rice straw on chewing activity, ruminal fermentation, and fibrolytic enzyme activity in growing goats were investigated in a $4{\times}4$ Latin Square experiment. The goats were offered four diets with an increasing proportion of rice straw (i.e. 0.05, 0.10, 0.15 and 0.20, respectively, on dry matter basis). Increasing level of rice straw increased ($P_{linear\;effect}$ <0.05) the time spent on eating, ruminating, and chewing. The ruminal pH and acetate: propionate ratio were increased ($P_{linear\;effect}$ <0.05), while the $NH_3$-N concentration was decreased ($P_{linear\;effect}$ <0.01). Increasing level of rice straw in the diet increased ($P_{linear\;effect}{\leq}0.01$) molar proportion of acetate and isovalerate, and decreased ($P_{linear\;effect}$ <0.01) molar proportion of propionate. The CMCase, xylanase and cellobiase activities in the rumen were decreased ($P_{linear\;effect}$ <0.05) with increasing level of dietary rice straw, whereas the avicelase activity was increased ($P_{linear\;effect}$ <0.01). In summary, increased level of rice straw elevated the dietary neutral detergent fibre (NDF) content in the diet and had a great impact on chewing activity and ruminal fermentation.

• Asian-Australasian Journal of Animal Sciences
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• 제25권1호
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• pp.66-74
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• 2012

The effects of exogenous fibrolytic enzymes (EFE; a mixture of two preparations from Trichoderma spp., with predominant xylanase and ${\beta}$-glucanase activities, respectively) on colonization and digestion of ground barley straw and alfalfa hay by Fibrobacter succinogenes S85 and Ruminococcus flavefaciens FD1 were studied in vitro. The two levels (28 and 280 ${\mu}g$/ml) of EFE tested and both bacteria were effective at digesting NDF of hay and straw. With both substrates, more NDF hydrolysis (p<0.01) was achieved with EFE alone at 280 than at 28 ${\mu}g$/ml. A synergistic effect (p<0.01) of F. succinogenes S85 and EFE on straw digestion was observed at 28 but not 280 ${\mu}g$/ml of EFE. Strain R. flavefaciens FD1 digested more (p<0.01) hay and straw with higher EFE than with lower or no EFE, but the effect was additive rather than synergistic. Included in the incubation medium, EFE showed potential to improve fibre digestion by cellulolytic ruminal bacteria. In a second batch culture experiment using mixed rumen microbes, DM disappearance (DMD), gas production and incorporation of $^{15}N$ into particle-associated microbial N ($^{15}N$-PAMN) were higher (p<0.001) with ammoniated (5% w/w; AS) than with native (S) ground barley straw. Application of EFE to the straws increased (p<0.001) DMD and gas production at 4 and 12 h, but not at 48 h of the incubation. EFE applied onto S increased (p<0.01) $^{15}N$-PAMN at 4 h only, but EFE on AS increased (p<0.001) $^{15}N$-PAMN at all time points. Prehydrolysis increased (p<0.01) DMD from both S and AS at 4 and 12 h, but reduced (p<0.01) $^{15}N$-PAMN in the early stage (4 h) of the incubation, as compared to non-prehydrolyzed samples. Application of EFE to barley straw increased rumen bacterial colonization of the substrate, but excessive hydrolytic action of EFE prior to incubation decreased it.

• 한국수산과학회지
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• 제9권1호
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• pp.13-18
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• 1976

주름을을 준 상태의 매듭그물강의 매듭의 강도를 조사하기 위해, 길이가 70cm 되는 2개의 그물실로 매듭을 만들고 인정한 2재의 다리가 이루는 각 $\varphi$를 $O^0$(매듭의 세로방향)로 부터 $180^{\circ}$(매듭의 가로방향)까지 변화시켜, 12개의 점에서 그 강도를 측정했다. 또한, $45^{\circ}$의 $\varphi$에 전개해 있는 다리중 어떤 1개의 다리를 각 $\varphi(0^{\circ}\~30^{\circ})$로 들어 올려 4개의 점에서 그 강도를 측정했다. 그물실의 재료는 mono-filament, multi-filament 및 spun 그물실로 구분하여 10종류를 사용했다. 실험의 결과, $\varphi$가 증가함에 따라서 바른매듭의 강도는 거의 직선적으로 감소하고 막매듭의 강도는 거의 직선적으로 증가했다. $\varphi$가 $100^{\circ}$이하에서는 바른매듭이 막매듭보다 강하고, $100^{\circ}$이상에서는 그 반대였다. $\varphi'$가 증가할수록 매듭의 강도는 지수함수적으로 감소했다. 이들 $\varphi,\varphi'$에 의한 매듭강도의 변화는 전보에서 제시한 매듭강도의 식에 의한 변화경향과 거의 일치하는 것 같았다.

• Composites Research
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• 제30권4호
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• pp.241-246
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• 2017

취성을 가진 섬유강화플라스틱은 충격을 받을 때 충격에너지를 흡수하면서 섬유와 기지재 간 계면에서 탈착 및 박리가 일어난다. 이는 복합재료의 에너지 충격흡수정도의 지표로 삼을 수 있다. 복합재료의 취성을 해결하기 위해 pine과 복합재료의 접착에 대한 연구가 되어 지고 있다. 이번 연구에서는 열처리 된 pine이 탄소섬유강화복합재료와 에폭시 접착제를 이용하여 접착되었다. 최적의 열처리 조건을 확인하기 위해, pine을 160도 및 200도 조건하에 열처리를 하였다. Pine 및 pine/탄소섬유복합재료의 기계적 및 계면물성을 파악하기 위해 인장, 인장중첩전단 및 아이조드 실험을 하였다. 또한, 열처리에 따른 나뭇결간의 결합력을 확인하기 위해 나뭇결 수직방향으로 인장시편 제조 후 파단될 때 탄성파를 음향방출시스템을 이용하여 분석하였다. 160도 조건으로 열처리 했을 때 나무강화 효과로 기계, 계면 및 나뭇결간의 결합력이 좋은 것을 확인하였다. 그러나 과한 열을 주게 되면 열에 약한 헤미셀룰로오스가 분해되면서 잡아주는 인자가 줄어들어 물성이 감소하였다.

• 농업과학연구
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• 제3권2호
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• pp.184-191
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• 1976

북방형(北方型) 목초(牧草)의 하고성(夏枯性) 방제(防除)하기 위하여 1976년(年) 7월(月)1일(日)부터 8(월)月14일(日)까지 Orchard grass, Tall fescue, Red clover, Alfalfa, Crabgrass의 5초종(草種)에 보리짚을 $100g/m^2$, $200g/m^2$, $300g/m^2$ 피복(被覆)하고 목초(牧草)의 성장(成長), 수량(收量) 및 영양성분(營養成分)에 미치는 영향(影響)을 검토(檢討)한 결과(結果) 다음과 같은 결론(結論)을 얻었다. 보리짚 피복(被覆)에 의하여 피복구(被覆區) 지온(地溫)은 무처리구(無處理區)에 비(比)하여 $1.0{\sim}3.04^{\circ}C$의 강하현상(降下現象)을 나타내었다. 피복처리구(被覆處理區)는 무처리구(無處理區)에 비(比)하여 6.0~45%의 성장효과(成長效果)를 나타내었다. $100g/m^2$ 피복구(被覆區)는 무처리구(無處理區)에 비하여 32.77%의 증수효과(增收效果)를 나타내었고 $300g/m^2$구(區) 이상은 부식(腐蝕)에 의하여 7.75%의 감수현상(減收現象)을 표현(表現)하였다. 피복처리구(被覆處理區)에서 생산된 목초(牧草)는 무처리구(無處理區)에 비하여 조단백질(粗蛋白質) 및 가용무질소물(可溶無窒素物)의 증가(增加)를 가져왔고 조지방(粗脂肪), 조섬유(粗纖維) 및 조회분(粗灰分)은 감소현상(減少現象)을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권11호
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• pp.1579-1584
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• 2002

Twelve adult male crossbred (Sahiwal${\times}$Holstein Friesian) cattle were distributed into four groups of three each on body weight basis. Animals were given wheat straw as a basal diet. The animals of group I and II were supplemented with concentrate mixture and animals of group III and IV were supplemented with cold processed urea molasses mineral block (UMMB). Thirty mg monensin/day/animal was supplemented to the animals of group II and 35 ppm monensin were incorporated in the UMMB supplemented to the animals of group IV. Vit.A and D mixture was given to all the animals once a week. Dry matter (DM) intake (kg/d) through wheat straw was 19.0 percent higher in the UMMB (without monensin) supplemented group (group III) than those of the concentrate mixture (without monensin) supplemented group i.e. group I. Total DM intake (kg/d) was lower in the monensin supplemented groups than those of non-supplemented groups though differences were not statistically significant. Digestible dry matter, organic matter (OM), crude protein (CP) and total digestible nutrients (TDN) intake were similar in all the groups. Average block consumption for 45 d period in the group III (0.95 kg/d) and group IV (0.84 kg/d) did not differ significantly. DM digestibility (%) was significantly (p<0.01) higher in the group II (58.9) as compared to the group I (52.7) and group III (54.0) but similar to the group IV (57.2). OM digestibility was also significantly (p<0.05) higher in the group II (63.2) as compared to that of the group I (54.9) but similar to the group III (57.8) and IV (59.2). Ether extract (EE) digestibility was significantly (p<0.01) higher in the group I (76.9) and II (80.3) as compared to the group III (59.87) and IV (55.77). Nitrogen free extract (NFE) digestibility was significantly (p<0.05) higher in the group II (62.38) as compared to that of the other groups. Crude protein (CP) and crude fibre (CF) digestibilities were not affected either due to UMMB or monensin. Nitrogen balance did also not differ significantly among the groups. However, Ca and P balance (g/d) in the group III (3.1, 1.3) and IV (3.0, 1.4) were significantly (p<0.01) higher than those of the group I (0.6, 0.2) and II (0.4, 0.3). Blood glucose (mg/100ml) was significantly (p<0.01) higher in the group II (65.2) and IV (65.2) as compared to the group I (55.2) and group III (53.9). Plasma urea-N level (mg/100 ml) in the group III (19.0) and IV (17.8) were significantly (p<0.01) higher than that of the group I (10.5) and II (12.3). So, monensin supplementation either with cold process UMMB or concentrate mixture did not show any additional effect on feed intake and digestibility but increases blood glucose level in adult cattle.

• Asian-Australasian Journal of Animal Sciences
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• 제15권4호
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• pp.522-527
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• 2002

The experiment was conducted for a period of 56 days with twelve Bangladeshi bull calves of average body weight of $127.20{\pm}11.34$ kg. The calves were divided into 3 groups having 4 animals in each. The animals were fed urea-treated rice straw designated as A) 4% urea-treated rice straw, B) 4% urea+4% soybean-treated rice straw and C) 4% urea+6% soybean-treated rice straw. In addition, all the animals were supplied 2 kg green grass, 350 g Til-oil-cake and 100 g common salt per 100 kg body weight of animals. Straw was treated with 4% urea solution and soybean meal at 4 and 6% were added to treated straw and kept for 48 h in double layer polythene bags under anaerobic condition. Urea treatment improved crude protein (CP) content of rice straw from 2.68 to 8.70% and it was further increased by 10.74 and 12.12% with the addition of 4 and 6% soybean meal. Dry matter (DM) intake (kg) was higher (p<0.05) in C (4.2) followed by B (4.1) and A (4.0). Crude protein intake was significantly higher (p<0.05) in group B and C than group A. Total live weight gains were 20.2, 24.8 and 25.6 kg for calves of group A, B and C respectively (p<0.01). The addition of soybean meal to treated rice straw did not affect the coefficients of digestibility of DM, OM, EE and NFE. However, CP and CF digestibility were significantly higher in group B and C (p<0.05). The values for digestible crude protein (DCP), digestible ether extract (DEE), digestible nitrogen free extract (DNFE) and total digestible nutrients (TDN) were significantly (p<0.05) higher in diet C and B in comparison to diet A, but there were no significant difference in digestible organic matter (DOM) and digestible crude fibre (DCF) value among the groups. It may be concluded that 4% urea treated rice straw can be fed to growing bull calves with 2 kg green grass and a small quantity of concentrate without any adverse effect on feed intake and growth. Moreover, soybean meal at 4 and 6% can be added to urea treated rice straw at the time of treatment for rapid hydrolyzing of urea, which resulted an improvement in nutrient digestibility and better utilization of rice straw for growth of growing bull calves.

• Asian-Australasian Journal of Animal Sciences
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• 제13권12호
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• pp.1674-1680
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• 2000

A study was conducted to compare the feeding value of urea treated and untreated mustard straw (MS) for sheep. Treated MS was prepared by adding urea-N at 1.84% and followed by packing in a pit silo for 21 days. Two groups of six empty Avikaline ewes were fed untreated (UTMS) and treated (TMS) mustard straw along with 200 g concentrate per head daily for 90 days. Untreated MS had 0.41% N and the urea treatment increased its N value to 1.58 %. The cell wall constituents were decreased in the TMS except for cellulose which remained unaffected. Dry matter intake of TMS was consistently higher than that of UTMS. Digestibility of DM, OM and fibre fractions of MS improved by the urea treatment. Ewes in both groups were in positive N balance while % N retention was lower in UTMS (26.30%) than in TMS (52.14%). The TMS fed group on average consumed 30.2 g DM, 2.9 g digestible crude protein and $0.2MJ\;DE\;per\;kg\;BW\;day^{-1}$ and maintained their weight whereas, the UTMS fed ewes lost weight. The VFA concentration in rumen liquor was higher in TMS than in UTMS. Total-N, ammonia-N and TCA-precipitable-N were also higher in TMS fed ewes. Blood glucose concentrations in the two groups were similar at initiation of the study. However the glucose concentration of UTMS fed group was significantly (p<0.01) lower than those fed UTMS at the termination of the study. Urea-N concentration was also higher in TMS fed group after 90 days of feeding period. It is concluded that urea treatment of MS improved N value of MS from 0.41% to 1.58% along with sizable improvement in nutritive value and in conjunction with 200 g concentrate, TMS can serve as maintenance ration for sheep. ($ME_{lakt}/ME_{m}=1.46$).

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1455-1463
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• 2006

Effects of different levels of molasses in a concentrate supplement on milk yield of cows grazing Setaria grass pastures were investigated. Thirty Friesian cows, 6-7 years old with mean pre-experimental body weight of $428{\pm}6.5$ kg, in early stage of lactation were randomly allotted to five dietary treatments in a completely randomized design experiment that lasted for 126 days. Experimental dietary treatments were forage alone and forage/concentrate mixtures with molasses included at 0, 5, 10 or 15% levels designated as $T_1$, $T_2$, $T_3$, $T_4$ and $T_5$, respectively. The parameters studied were voluntary dry matter (DM) intake, average daily live weight change (LWC), milk yield, body condition score (BCS) and apparent nutrient digestibility coefficients. The DM and energy contents of Setaria grass were low compared to the concentrate diets. Fibre fractions-NDF, ADF, ADL, hemicellulose and cellulose; and gross energy were higher in concentrate mixtures than in the forage. Total DM intake (forage+concentrate mixtures) was significantly higher (p<0.001) in cows on the concentrate mixtures. LWC was not significantly different (p>0.05) between the cows. Average milk yields were significantly different (p<0.05) between cows. Fat corrected milk (FCM) was similar among cows in the treatments. BCS was better (p<0.001) in cows on concentrate mixtures. Digestibilities of DM, CP, NDF, ADF, ADL, OM, and energy were significantly higher (p<0.001) in cows on $T_2$, $T_3$, $T_4$ and $T_5$ than in those on $T_1$. There were no significant differences in the digestibility of DM, CP, NDF, ADF and ADL (p>0.001) in cows on concentrate mixtures. This study therefore demonstrated that lactating dairy cows in Fiji need a level of readily fermented energy source such as molasses in their diets; however, a level above 10% is not nutritionally suitable for lactating dairy cows. Based on data on production parameters-milk yield, fat corrected milk, body condition score and apparent nutrient digestibility coefficients-molasses levels that range between 5-10% are recommended, however, 10% is the best and therefore recommended for inclusion in the concentrate mixture of lactating dairy cows on a basal diet of Setaria sphacelata in Fiji.