• Environmental Engineering Research
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• 제24권2호
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• pp.347-353
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• 2019

Although membrane distillation (MD) has great promise for desalination of saline water sources, it is crucial to improve its thermal efficiency to reduce the operating cost. Accordingly, this study intended to examine the thermal energy efficiency of MD modules in a pilot scale system. Two different modules of hollow fiber membranes were compared in direct contact MD mode. One of them was made of polypropylene with the effective membrane area of $2.6m^2$ and the other was made of polyvinylidene fluoride with the effective membrane area of $7.6m^2$. The influence of operation parameters, including the temperatures of feed and distillate, feed flow rate, and distillate flow rate on the flux, recovery, and performance ratio (PR), was investigated. Results showed that the two MD membranes showed different flux and PR values even under similar conditions. Moreover, both flow rate and temperature difference between feed and distillate significantly affect the PR values. These results suggest that the operating conditions for MD should be determined by considering the module properties.

• 생명과학회지
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• 제20권2호
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• pp.231-236
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• 2010

CS682의 육계 및 이유자돈에서 사료첨가제로서의 기능성을 검정하기 위해 병아리에 28일간 0.1%, 1%의 농도로 사료에 첨가, 급여하여 질병예방기능, 성장기능, 사료효율기능 및 안전성 평가를 실시한 결과, 위장관계 기능 장애를 일으키지 않고, 생체대사에 영향을 미치지 않으면서 사료효율을 높이는 것으로 나타났다. CS682 투여 후 14일째에는 각 군 간에 증체량 및 사료효율에서 차이가 미미하였으나, 28일째에는 대조군에 비해 0.1%군은 115.64, 1%군은 122.49%의 사료효율을 보여 각 군 간에 큰 차이를 나타내었다. 그리고 28일째 각 군에서 채혈한 혈액의 기본 혈구검사를 실시한 결과 각 군 간에 유의적인 차이를 보이지 않고 모두 정상 범위를 나타낸 것으로 보아 CS682는 생체대사에 영향을 미치지 않는 것으로 보인다. 또한 이유자돈에서 28일간 0.1%의 농도로 사료에 첨가, 급여하여 질병예방기능, 성장기능, 사료효율기능 및 안전성 평가를 실시한 결과에서 임상적으로 특이한 부작용 없이 대조군에 비하여 높은 사료효율을 나타냈다. 결론적으로 육계와 이유자돈에서 CS682의 사료첨가는 생체대사에 영향을 미치지 않고, 소화기 이상 증상을 유발하지도 않으면서 사료효율을 효과적으로 증가시키는 것으로 나타났다. 본 결과를 토대로 육계 및 이유자돈에서 안전하게 증체율 및 사료효율을 증가시킬 목적으로 CS682를 사료에 첨가하는 것이 효과적일 것으로 생각된다.

• 한국어병학회지
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• 제15권1호
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• pp.37-42
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• 2002

Effect of mercury (Hg) toxicity on survival, growth, feed efficiency and oxygen consumption were examined in the juvenile olive flounder. Paralichthys olivaceus. Fishes were exposed to sublethal concentrations of Hg ranging from 0 to 0.13mg/L for 6 weeks. Hg reduced survival rate in a concentration and exposure period-dependent way and suddenly reduction occurred at Hg concentrations greater than 0.05mg/L after 6 weeks. Growth rate and feed efficiency also significantly decreased at greater than 0.028 and 0.05 mg/L respectively. Oxygen consumption rate was significantly decreased to 25 and 32% than that of the control at the Hg concentration of 0.05 and 0.13 mg/L respectively. These results suggest that Hg toxicity inhibit physiological function including growth, feed efficiency and oxygen consumption in the juvenile olive flounder, resulting in survival failure at high concentration.

• 대한수의학회지
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• 제14권2호
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• pp.237-241
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• 1974

A number of chemotherapeutic agents, namely antibiotics, sulfonamides and nitrofuran derivatives have been used, as a fred additive, for the purposes of growth improvement of chicken, increase of feed efficiency, decrease of animal mortality, and disease prevention. In these experiments, furamizole which is one of nitrofuran derivatives and feed additive was test, in field, its antibacterial activity against Mycoplasma gallisepticum causing air sac disease, its effect on pullorum disease control, its effect on the lowering the mortality of chicken and finally the increase of feed efficiency. Throughout the studies, furamizole, in concentration of 0.025% in feed fed to baby chicken continuously resulted as following: 1. Tested chicken showed no avian mycoplasma infection compared to 3.7% outbreak in control chicken. 2. Tested chicken showed a low degree of outbreak of pullorum disease. However, its outbreak was much more surpresed compared to that of control chicken. 3. Total mortality rate of 5.5% and 30.8% were obtained in test and control chicken respectively. 4. Feed efficiency were 2.83 and 2.97 in test and control chicken respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제14권3호
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• pp.316-320
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• 2001

Sixteen growing crossbred Anglo-Nubian goats, 10-12 months old, pre-experimental average body weights of $18.3{\pm}0.28kg$ were randomly allotted to four diets to investigate the efficiency of utilisation of diets containing increasing levels of desiccated coconut waste meal (DCWM) in the tropical environment of Samoa, South Pacific region. The four diets were designated as 1, 2, 3 and 4. Diet 1 that has no DCWM served as the control, while diets 2, 3 and contained different levels of DCWM. Voluntary concentrate intake, growth rate, feed efficiency and nutrient digestibility coefficients were measured. Gross energy (GE) and organic matter (OM) values of the diets increased linearly with increase in the levels of DCWM in the diets. Voluntary concentrate intake decreased with increasing proportion of DCWM in the diets. Forage intake increased with increase in the levels of DCWM diets offered to the growing goats. Total voluntary feed intakes were statistical significant (p<0.05) and the goats on diet 4 had the least intake followed by those on diet 3. Goats an diets 1 and 2 were different in total feed intake but not at a significant level (p>0.05). Feed efficiency (FE) followed the trend of voluntary concentrate intake and daily live weight gains. Dry matter digestibility (DMD) was significantly different (p<0.05) among the goats offered the different diets. DMD improved with increasing levels of DCWM. The goats accepted all, the diets that were compounded with the different levels of dried DCWM and this seems to suggest that DCWM have no deleterious effects. However, the best level at which dried DCWM could replace brewers dried grains in the diets of growing goats is at 38.5% (diet II). Based on voluntary feed intake, live-weight gain and apparent nutrient digestibility coefficients of the goats it could be concluded that DCWM based diets merits further attention as a locally available feed source in ruminants nutrition in the Pacific Island countries where feed availability is seasonal.

• 한국양식학회지
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• 제19권2호
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• pp.95-98
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• 2006

This study was performed to determine possibility of compensatory growth of juvenile olive flounder fed a commercial feed during the summer season. Five treatments of fish with triplicates were prepared: C, S1, S2, S3 and S4. Fish in the control group (C) was hand-fed with the commercial feed to apparent satiation twice daily for 6 days a week during 6 weeks. Fish in S1, S2, S3, and S4 experienced 1, 2, 3, and 4 weeks of starvation before fed to satiation twice daily for 5, 4, 3, and 2 weeks, respectively. The feeding trial lasted far 6 weeks. Survival of flounder in C, S1 and S2 was significantly (P<0.05) higher than that offish in S4. Weight gain and specific growth rate (SGR) of flounder in C and S1 were significantly (P<0.05) higher than those of fish in S2, S3 or S4. And weight gain and SGR of flounder in S2 and S3 were significantly (P<0.05) higher than those of fish in S4. Feed consumption of flounder tended to increase with weeks of feeding. Feed efficiency ratio and protein efficiency ratio for flounder in C, S1, S2 and S3 were significantly (P<0.05) higher than those for fish in S4. Moisture content of the whole fish in C was lowest, but highest for fish in S4, respectively. Crude protein content of the whole fish in C was highest, but lowest far fish in S4, respectively. Crude lipid content of the whole fish in C, S1 and S2 was significantly (P<0.05) higher than that of fish in S4. In conclusion, full compensatory growth was obtained in juvenile olive flounder fed for 5 weeks after 1-week feed deprivation during the summer season. Compensatory growth of fish was well supported by improvement in feed efficiency ratio and protein efficiency ratio.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1470-1477
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• 2006

One hundred and sixty crossbred pigs ($6.62{\pm}0.36kg$) weaned at day $18{\pm}1$ were used to investigate the effects of lactitol and tributyrin on performance, small intestinal morphology and enzyme activity. The pigs were assigned to one of five dietary groups (4 pens/diet with 8 pigs/pen) and were fed the negative control diet or the negative control diet supplemented with 10 g/kg glutamine (as a positive control), or 3 g/kg lactitol (${\beta}$-D-galactopyranosyl-($1{\rightarrow}4$)-D-sorbitol), or 5 g/kg tributyrin (butanoic acid 1,2,3-propanetriyl ester), or 3 g/kg lactitol+5 g/kg tributyrin. Body weight and feed intake were measured weekly during the 4-week study. On day 7, four pigs per dietary treatment were sacrificed to examine small intestinal morphology and enzyme activity. The results showed that: (1) Compared with the negative control diet, the positive control diet improved weight gain and feed efficiency during weeks 1-2 and over the entire study (p<0.05), and also decreased duodenal and ileal crypt depth (p<0.05), but did not alter intestinal enzyme activity (p>0.05). Lactitol improved feed efficiency during weeks 3-4 and over the entire study (p<0.05), but did not improve weight gain and feed intake, intestinal morphology or enzyme activity (p>0.05). Tributyrin improved weight gain and reduced feed/gain during weeks 3-4 and over the entire study. Tributyrin significantly decreased crypt depth in the duodenum and ileum, and increased duodenal lactase and ileal maltase activity (p<0.05). Lactitol+tributyrin increased weight gain during weeks 3-4 and over the entire study, and improved feed efficiency during weeks 1-2 and 3-4 and over the entire study (p<0.05). Lactitol+tributyrin increased the jejunal villus height, and decreased the duodenal and ileal crypt depth (p<0.05). Lactitol+tributyrin also increased jejunal lactase and sucrase activity (p<0.05). (2) Compared with the positive control, tributyrin improved weight gain and reduced feed/gain during weeks 3-4 (p<0.05), decreased the ileal crypt depth, and improved the duodenal lactase and sucrase activity (p<0.05). Lactitol+ tributyrin improved weight gain during weeks 3-4, improved feed efficiency during weeks 3-4 and over the entire study, increased the ileal villus height, and increased jejunal lactase, sucrase and maltase activity (p<0.05). These results showed that tributyrin improved performance, intestinal morphology and enzyme activity, while the effect of lactitol was very limited. These results also showed that, compared with glutamine, tributyrin was more effective in improving intestinal morphology and enzyme activity, and tributyrin exerted a superior effect in improving performance as weaning progressed. These observations suggest that, as a chemical for repairing intestinal atrophy, glutamine and tributyrin should be used in the first and second periods of the starter phase, respectively.

• 농업생명과학연구
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• 제45권4호
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• pp.95-103
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• 2011

본 연구는 한우 거세우 95두 (평균체중 226 kg)를 이용하여 농후사료와 조사료 분리급여구, TMR구 그리고 TMR을 발효시킨 F-TMR구로 나누어 22개월동안 사육하여 도축하였을 때, 사료효율, 도체성적 및 경제성분석에 미치는 영향을 조사하기 위하여 실시되었다. 건물 및 TDN 섭취량은 육 비육 각 단계별로 F-TMR구에서 가장 많았다 (p<0.05). F-TMR구의 경우, 일일증체량은 육성기에는 처리구중 가장 적었으나, 비육후기에는 타 처리구에 비해 약 48%나 높았다 (p<0.05), 사료효율은 전 육성비육기간 동안 비슷한 수준으로 유지되었다. 도체중과 배최장근단면적에서는 F-TMR 급여구에서 가장 높았으나 (p<0.05), 등지방두께가 가장 얇았던 (p<0.05) 분리급여구에서 육량지수와 육량 A등급 비율이 높았다. F-TMR구의 근내지방도가 타구에 비해 현저히 (p<0.05) 증가되어 육질 1+등급이상 출현율이 96%에 달하였다. 경제성 분석에서 사료비는 F-TMR구가 분리급여구에 비해 40%가 증가되었으나 증체량과 육질등급의 향상으로 인하여 순수익은 29%나 증가되었다.

• 한국수산과학회지
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• 제42권3호
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• pp.257-261
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• 2009

Two feeding trials were conducted to investigate the effects of several dietary additives on growth and feed utilization of juvenile flounder. In the first experiment, three replicate groups of juveniles (average weight 1.5 g) were fed diets with or without wasabi extract and chitosan for 7 weeks. Survival rate, weight gain, protein efficiency ratio, hepatosomatic index and condition factor were not affected by the different dietary additives (P>0.05). Feed efficiency of fish fed the wasabi extract diet was significantly higher than that of fish fed the control diet (P<0.05). Daily feed intake of fish fed the wasabi extract diet was significantly lower than that of fish fed the other diets (P<0.05). In the second experiment, three replicate groups of juveniles (average weight 1.4 g) were fed diets with or without Pophyra powder for 7 weeks. Survival rate and weight gain were not significantly affected by dietary Pophyra powder (P>0.05). Feed efficiency and protein efficiency ratio of fish fed the Pophyra diet were significantly lower than those of fish fed the control diet (P<0.05). The results of these experiments suggest that feed efficiency of juvenile flounder may be improved by dietary supplementation with wasabi extract.

• 농업과학연구
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• 제42권3호
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• pp.253-259
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• 2015

This study was conducted to investigate the effect of different additives on the growth performance, feed efficiency and carcass characteristics in Holstein steers during 18month fattening periods. Twenty four Holstein steers, 5months of age and 176.6kg, were randomly allocated to 3 experimental groups 8 animals each for 18-months feeding trial. The groups were control (not additive), T1 (fed zinc, Vitamin C) and T2 (fed zinc, Vitamin C, Vitamin B6 and Selenium). According to feeding additives, final weight was not significantly different among the treatment groups, tended to be high at T2 group (827kg) compared to the other groups. Average daily gain was not different among the treatment groups during the experimental periods, but T2 group was significantly greater than T1 group in growing stage (p<0.05). The feed additives had no effects on DMI during experimental periods. Feed conversion ratio of T1 group in growing stage was significantly higher than those of other groups (p<0.05), average feed conversion ratio was tend to be decreased at T2 group rather compared with other groups. In the results of yield traits, carcass weight were relatively higher in T2 group than other groups (p<0.05). Rib-eye area, back fat thickness and yield index were similar between groups. In quality traits, marbling, meat color, fat color, texture and maturity were not significantly different among the groups. In economic efficiency, income was highest at T2 group as 91~393 thousand won among 3 groups.