• Asian-Australasian Journal of Animal Sciences
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• 제24권2호
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• pp.285-294
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• 2011

The abatement of methane emission from ruminants is an important global issue due to its contribution to greenhouse gas with carbon dioxide. Methane is generated in the rumen by methanogens (archaea) that utilize metabolic hydrogen ($H_2$) to reduce carbon dioxide, and is a significant electron sink in the rumen ecosystem. Therefore, the competition for hydrogen used for methanogenesis with alternative reductions of rumen microbes should be an effective option to reduce rumen methanogenesis. Some methanogens parasitically survive on the surface of ciliate protozoa, so that defaunation or decrease in protozoa number might contribute to abate methanogenesis. The most important issue for mitigation of rumen methanogenesis with manipulators is to secure safety for animals and their products and the environment. In this respect, prophylactic effects of probiotics, prebiotics and miscellaneous compounds to mitigate rumen methanogenesis have been developed instead of antibiotics, ionophores such as monensin, and lasalocid in Japan. Nitrate suppresses rumen methanogenesis by its reducing reaction in the rumen. However, excess intake of nitrate causes intoxication due to nitrite accumulation, which induces methemoglobinemia. The nitrite accumulation is attributed to a relatively higher rate of nitrate reduction to nitrite than nitrite to ammonia via nitroxyl and hydroxylamine. The in vitro and in vivo trials have been conducted to clarify the prophylactic effects of L-cysteine, some strains of lactic acid bacteria and yeast and/or ${\beta}$1-4 galactooligosaccharide on nitrate-nitrite intoxication and methanogenesis. The administration of nitrate with ${\beta}$1-4 galacto-oligosaccharide, Candida kefyr, and Lactococcus lactis subsp. lactis were suggested to possibly control rumen methanogenesis and prevent nitrite formation in the rumen. For prebiotics, nisin which is a bacteriocin produced by Lactococcus lactis subsp. lactis has been demonstrated to abate rumen methanogenesis in the same manner as monensin. A protein resistant anti-microbe (PRA) has been isolated from Lactobacillus plantarum as a manipulator to mitigate rumen methanogenesis. Recently, hydrogen peroxide was identified as a part of the manipulating effect of PRA on rumen methanogenesis. The suppressing effects of secondary metabolites from plants such as saponin and tannin on rumen methanogenesis have been examined. Especially, yucca schidigera extract, sarsaponin (steroidal glycosides), can suppress rumen methanogenesis thereby improving protein utilization efficiency. The cashew nutshell liquid (CNSL), or cashew shell oil, which is a natural resin found in the honeycomb structure of the cashew nutshell has been found to mitigate rumen methanogenesis. In an attempt to seek manipulators in the section on methane belching from ruminants, the arrangement of an inventory of mitigation technologies available for the Clean Development Mechanism (CDM) and Joint Implementation (JI) in the Kyoto mechanism has been advancing to target ruminant livestock in Asian and Pacific regions.

• 대한토목학회논문집
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• 제2권3호
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• pp.23-32
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• 1982

본연구(本硏究)는 다절기(多節期)에는 저온(低溫)으로 하절기(夏節期)에는 고온(高溫)으로 혐기성(嫌氣性) 소화조(消化槽)를 운전(運轉)시킬 수 있는지를 검토(檢討)하기 위한 것으로 실험실(實驗室) 완전혼합형(完全混合型) 혐기성(嫌氣性) 소화조(消化槽)를 $18.5^{\circ}C$ 부터 $60^{\circ}C$까지의 11단계(段階)의 온도(溫度)에서 유기물질(有機物質)의 제거효율(除去効率) 가스생산량(生産量)을 서로 비교(比較)하였다. $35^{\circ}{\sim}40^{\circ}C$ 내외(內外)에서 BOD와 VS 제거효율(除去効率)은 각각(各各) 71%와 53%였으며 이 온도(溫度)에 있어서 가스생산량(生産量)은 주입분뇨량(注入糞尿量)의 16배(倍) 또는 $0.63m^3gas/kg$ VS fed 였다. 화조(消化槽) 유출수(流出水)를 심전(沈殿)시키면 BOD제거효율(除去効率)은 78%까지 상계(上界)하였다. 본실험(本實驗)의 결과(結果)는 $32^{\circ}$에서 $47^{\circ}C$로 운전(運轉)시킨 기존(旣存) 분뇨처리장(糞尿處理場)의 결과(結果)와 $40^{\circ}C$까지는 비교적(比較的) 잘 맞았으나 $40^{\circ}C$ 이상(以上)에서는 실험실(實驗室) 결과(結果)가 처리효율(處理効率)이나 가스생산량(生産量)으로 볼 때 양호(良好)하였다. 분뇨(糞尿)에 정화조폐액(淨化槽廢液)이나 우분(牛糞) 혼합처리(混合處理) 가능성(可能性) 검토(檢討)하였는데 1:1로 혼합처리(混合處理)시켰을 때의 BOD제거효율(除去効率)이나 가스생산량(生産量)이 분뇨(糞尿)만의 처리시(處理時)와 별로 차이(差異)가 없었다. 한편 혐기성(嫌氣性) 소화조(消化槽)의 유출수(流出水)를 희석(稀釋)없이 호기성처리(好氣性處理)도 가능(可能)한지 알아 보았는데 이때의 BOD와 SS제거효율(除去効率)은 98% 이상(以上)이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권8호
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• pp.1138-1143
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• 2001

A total of 96 piglets were weaned at 19 and 13 days in Exp. 1 and 2, respectively, and allotted to one of four diets: three with different spray dried plasmas (SPs) and one with hydrolysed casein (HC). SPs were from pigs (SPP), mixed origin (SMP), and mixed origin with standardized level of immunoglobulins (SMPIG). All the diets contained 1.7% total lysine, 25% of the test protein source, 45% corn starch, 15% lactose, 2% sucrose, 7% soybean oil. At d 4 and d 2 in Exp. 1 and 2, respectively, piglets were perorally challenged with $10^{10}$ CFU E. coli K88. Growth performance, immunity, and health condition were measured for 15 days and 14 days in Exp. 1 and 2, respectively. To investigate apparent ileal digestibility and nutrient deposition, all piglets were sacrificed at d 14 in Exp. 2. In 1. 3 piglets died in HC diet and 1 in SPP diet. HC diet showed higher mortality (p<0.01) than other diets. In Exp. 2, no clinical sign of infection was detected, no difference for the content of E. coli K88 was found in feces at 4 and 6 days after the infection, and no E. coli K88 was found in the jejunum at the end of experiment. In both experiments, feed intake was lower for HC diet and ADG was 96, 106, 122 and 155 for HC, SPP, SMP and SMPIG diet, respectively (HC vs others, p<0.05; SMPIG vs other SP, p<0.01). Heal apparent digestibility of nitrogen in sacrificed piglets was higher for HC diet (p<0.05). After the challenge, K88-specific titers in saliva (Exp. 1) and in plasma (Exp. 2) were reduced in SMP and SMPIG. The piglets positive to the adhesion of the used E. coli strain to the intestinal brush borders had a significantly reduced growth (p<0.01) and a higher K88-specific IgA titer in plasma, in comparison with negative ones. This effect was independent of the diet. The data show the relevance of spray dried plasma sources and particularly of SP with standardized level of immunoglobulins for the feeding of early-weaned at the risk of infection by enterotoxigenic bacteria.

• 유기물자원화
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• 제7권2호
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• pp.57-64
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• 1999

본 연구는 고온호기발효법에 의해 미세조류(부영양화호에서 회수한)를 처리할 경우, 처리조건의 변화에 따른 지구온난화가스의 발생특성을 살펴, 가스억제를 위한 효과적 처리조건을 검토하는 것이다. 회분 및 연속실험을 실시하여, 이하의 결과가 얻어졌다. 회분실험에서는 폐식용유의 첨가유무 및 공기주입량에 따른 발효효과를 검토했다. 폐식용유 첨가의 경우, 발열량의 증가에 따라 처리물질의 수분증발에 효과적 이었다. 또 공기주입량의 변화에 따라, 유기물제거는 공기량이 100ml/min일 때 가장 효과적이었고, 발생가스중 $CO_2$는 실험초기에만 영향을 받았고, $N_2O$는 실험중 전혀 영향을 받지 않았다. 또 $CH_4$는 공기공급이 부족한 초기에 검지 되었으나, 그 후 발생되지 않았다. 연속실험에서 공기량을 100ml/min에 고정한 후,고분자응집제의 첨가유무 및 수분조정제의 종류에 따른 가스발생특성을 비교 검토했다. $N_2O$는 고분자응집제(PAC) 첨가 및 수분조정제의 종류에 의해 가스발생량에 영향을 받지 않았으나, $CO_2$의 경우는 약간의 영향을 받았다. $CH_4$는 검출되지 않았다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권1호
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• pp.80-85
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• 2006

Ninety six crossbred pigs (Landrace${\times}$Yorkshire${\times}$Duroc) were used to determine the effects of essential oils (Fresta F $Conc^{(R)}$) supplementation on growth performance, immune response and fecal noxious gas of weaned pigs. Treatments were 1) NC (negative control; basal diet without antibiotics), 2) PC [positive control; basal diet+CSP (CTC+Sulfathiazole+Penicillin) 0.1%], 3) NCF (basal diet+Fresta F $Conc^{(R)}$ 0.03%) and 4) PCF [basal diet+CSP (CTC+Sulfathiazole+Penicillin) 0.1%+Fresta F $Conc^{(R)}$ 0.02%]. From d 0 to 14, ADFI was increased in pigs fed PCF diet (p<0.05). From d 14 to 28, pigs fed PCF diet had greater ADG and ADFI than pigs fed NC diet (p<0.05). From d 28 to 49, ADG and ADFI in pigs fed PCF diet were higher than in pigs fed NC diet (p<0.05). Through the entire experimental period, ADG and ADFI in pigs fed PCF diet were the highest compared to pigs fed NC and PC diets (p<0.05). There was no significant difference in fecal consistency score among the treatments (p>0.05). No statistical differences (p>0.05) were found in red blood cells (RBC) counts, white blood cells (WBC) counts, lymphocyte counts, total protein and albumin. Serum IgG concentration of PCF treatment was greater than that of other treatments (p<0.05). From d 0 to 14, there was no significant difference in digestibility of dry matter and nitrogen among the treatments (p>0.05). From d 14 to 28, digestibility of dry matter in pigs fed PC, NCF and PCF diets was higher than that of pigs fed NC diet (p<0.05) and treatments with added essential oils were higher than other diets on digestibility of nitrogen (p<0.05). Also, from d 28 to 49, digestibility of nitrogen in pigs fed PCF diet was the highest among others (p<0.05). On d 14 and 28, no statistical differences (p>0.05) were found in volatile fatty acid (VFA), ammonia nitrogen ($NH_3$-N) and hydrogen sulfide ($H_2S$) concentrations among treatments. On d 49, there was no significant difference in VFA concentration among the treatments (p>0.05). $NH_3$-N concentration in pigs fed PCF diet was lower than in pigs fed other diets (p<0.05). $H_2S$ concentration in pigs fed diets with added essential oils was lower than others. In conclusion, the results suggest that the dietary addition of essential oils and antibiotics into diets for weanling pigs improved growth performance, IgG concentration and nitrogen digestibility and decreased noxious gas concentration. Essential oils can be used to partly replace antibiotics in diets for weaned pigs without negative affects on growth performance.

• 생물환경조절학회지
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• 제10권4호
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• pp.213-218
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• 2001

2000년 말 현재 전국 시설 재배면적은 52,189 ha이고 이중 가온 재배면적은 13,621 ha이다. 난방비용이 경영비중 차지하는 비중이 시설재배의 선진국의 15%에 비하여 25~30%을 차지하고 있어 난방비의 비중이 높다. 이러한 문제점을 해결하고자 가온시 시설의 난방공간을 최소화 할 수 있는 장치를 개발하여 처리별 환경 및 작물의 생육상태 및 연료소비량을 조사하였다. 시설내 난방용적을 보면 관행커튼이 661.5m$^3$에 비하여 상하이동 수평커튼은 264m$^3$로 약 60%을 줄일 수 있다. 시설억제 재배에 있어서 처리별 연료 소비량은 관행에 비하여 상하이동 커튼 설치시 28%, 그리고 반촉성 재배시에는 56%의 연료 절감의 효과가 있었고 추가로 시설내 온도 분포와 상대습도가 균일하였다. 상하이동 커튼구가 관행에 비하여 고추의 개화시기가 빨랐고 수확량도 증가하였다.

• 한국건설관리학회논문집
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• 제16권3호
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• pp.91-100
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• 2015

에너지 소비 절감 및 이산화탄소 배출 감소를 위한 노력의 일환으로 대다수의 선진국에서 리모델링 프로젝트를 장려하고 있으며, 이에 따라 건설산업에서 리모델링 사업은 큰 비중으로 성장하고 있다. 기존의 리모델링 관련 연구를 분석한 결과, 1) 리모델링 대안의 생성 및 선정 과정과 2) 건축물 경과년수에 따른 경제적 타당성 분석 결과가 제대로 반영되어 있지 않은 문제점이 있었다. 본 연구에서는 리모델링 대안에 따른 에너지절감량과 경제성을 동시에 고려하여 가장 비용효율적인 에너지절감형 리모델링 대안을 선정할 수 있는 의사결정 지원모델을 개발하였다. 개발된 프로세스 모델은 외피 시스템과 신재생에너지 설비를 조합한 "리모델링 솔루션"을 생성하며, 국제기준(ISO-13790, DIN V 18599)을 응용한 에너지성능평가, 생애주기비용 분석(LCCA)기법을 통한 경제성 평가를 실시하도록 구성되어있으며, 입력된 대안을 순환평가하여 최적의 대안을 출력하도록 구성하였다. 개발된 모델을 실제 사례에 적용한 결과, 비용효율적인 에너지절감형 리모델링 대안을 선정할 수 있는 것으로 확인하였다. 따라서 이 연구를 통해 개발된 모델은 리모델링을 계획하는 의사결정자(예: 발주자) 등에게 효율적인 대안 선정에 도움을 줄 수 있을 것으로 기대된다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권3호
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• pp.394-400
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• 2004

To investigate the efficacy of alternatives to antibiotics, the present study was conducted to compare the effects of antibiotic, lactic acid, a blend of commercial essential oils (EOs) and EOs in combination with lactic acid on growth performance and the functional activity of the gut in broiler chickens. A total of 168 broiler chickens were given the basal diet supplemented with 10 ppm colistin (T1), 0.1% lactic acid (T2), 25 ppm EOs (T3), 25 ppm EOs+0.1% lactic acid (T4), 50 ppm EOs (T5) or 50 ppm EOs+0.1% lactic acid (T6) in the period 3 to 35 days of age. As a result, the broiler chickens assigned to T4 group throughout the experimental period had apparently (p<0.05) greater body weight and total gain than these assigned to T1, T2, T3 and T5 groups. However, there was no difference in growth performance among the birds fed the diets supplemented with antibiotic (T1), lactic acid (T2) and EOs (T3 and T5) alone. The weights of digestive organs and the number of lactobacilli and E. coli in the lower ileum were not affected by dietary treatments. Total trypsin activity was significantly (p<0.05) greater in T4 than T1, T2, T3 and T5 groups. Total and specific pancreatic $\alpha$-amylase activities were significantly (p<0.05) enhanced in the broiler chickens fed T4 diet compared with these fed T1, T2 and T3 diets. However, there were no differences in growth performance and digestive enzyme activities including pancreatic trypsin and $\alpha$-amylase between T4 and T6 groups fed the diets supplemented with either low or high EOs levels in combination of lactic acid. In conclusion, a blend of commercial EOs combined with lactic acid showed significant increases in digestive enzyme activities of the pancreas and intestinal mucosa, leading to increase in growth performance.

• 대한환경공학회지
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• 제37권4호
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• pp.246-252
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• 2015

철강공장의 열연공정에서 발생하는 폐부산물인 mill scale을 원료로 하여 인흡착에 효율적인 무기흡착제인 magnetite를 생산하고자 하였다. Mill scale의 주요 구성성분은 wustite (FeO), magnetite (FeO), hematite (FeO)였으며, 산처리를 수행할 경우 대부분의 wustite가 magnetite와 hematite로 전환되었다. Mill scale의 산처리는 HCl과 $H_2O_2$를 이용하여, 염기처리는 NaOH 이용하여, 산-염기 복합처리는 $H_2SO_4$와 NaOH를 이용하여 수행하였다. Oil 제거 및 DI water로 rinsing만 한 경우, 인 흡착용량은 0.28 mgP/g으로 나타난 반면, 염기처리를 한 경우 0.68, 산처리를 한 경우 1.19 mgP/g으로 인 흡착용량이 증가하였다. 산-염기 복합처리 과정을 통해 단일상의 magnetite 입자를 얻을 수 있었으며, 이 입자의 인 흡착용량은 3.11 mgP/g 이상인 것으로 파악되었다. 산화철의 인 흡착에 대한 동력학적 특성 분석결과 Freundlich와 Langmuir 두 등온 흡착모델 모두 magnetite의 인 흡착 거동을 잘 모사하였다. Freundlich 모델의 흡착능(K)과 흡착강도(1/n)를 조사한 결과, 온도가 증가할수록 강한 흡착능을 보이는 것으로 나타났다. Langmuir 모델 적용결과 최대 흡착용량은 $20^{\circ}C$에서 5.1 mgP/g인 것으로 파악되었다.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2001년도 제18차 정기총회 및 학술발표 PROCEEDINGS
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• pp.24-39
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• 2001

These experiments were conducted to evaluate the nutritional and feeding value of red pepper seed oil meal (RPSOM) as local vegetable protein ingredients for poultry feeding. In the first experiment, nutritional values of RPSOM were evaluated by analyzing chemical compositions and determining true metabolizable energy (TME), nitrogen corrected TME (TMEn) and true available amino acid (TAAA) contents. According to the chemical analysis, RPSOM contained 22.50％ of crude protein, 4.75％ of ether extract, 27.70％ of crude fiber, 0.34 mg／g of capsaicin and 49.97 ppm of xanthophylls. The values of TME and TMEn determined by force-feeding 16 roosters (ISA-Brown) were 1.73 kcal／g and 1.63 kcal／g on dry matter basis, respectively. The average TAAA value of 16 amino acids measured by the force－feeding technique was 81.70％. These values were used for formulating experimental diets containing various levels of RPSOM for broiler chicks and laying hens. Two feeding trials were made to investigate the effects of dietary incorporation of RPSOM into chicken feed performances of broiler chicks and laying hens. In the broiler feeding (Exp. 2), a total of two hundred twenty-five, 4 wk old male broiler chicks (Ross) were randomly divided into 9 groups of 25 birds each and assigned to three experimental diets containing 0, 5 and 10% RPSOM. The birds were fed ad libitum the diets for 3 wk and feed intake, weight gain and feed conversion rate were determined. At the end of the feeding, the blood levels of glutamate oxaloacetate transaminase (GOT), gamma glutamyl transpeptidase (GGT), blood urea nitrogen (BUN) and cholesterol, and the body and fatty acid compositions of leg muscle were measured. No significant differences were observed in weight gain, feed intake, feed conversion rate, body composition, serum levels of GOT, GGT and BUN among the treatments. However, blood cholesterol level was lower (P＜0.05) in 10% RPSOM diet group than those in the other. The dietary RPSOM at 5 and 10% levels increased the content of linoleic acid (P＜0.05) in leg muscle compared to that of control group. The results indicate that RPSOM can be used for broiler feed up to 10% without any significant negative effects on broiler performance. In the layer feeding (Exp. 3), the effects of dietary RPSOM on the performances of laying hen were investigated by feeding ninety 45 wk old laying hens (ISA-Brown) with experimental diets containing 0, 5 and 10% RPSOM for 4 wk (30 birds per treatment). Measurements were made on egg production rate, egg weight, feed intake, Haugh unit, egg shell strength which was higher (P＜0.05) in layers fed 10% RPSOM diet compared to those fed 0 and 5% RPSOM diets. Thus, it can be concluded that RPSOM can be included into laying hen feed up to 10% without any harmful effects.