• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.1
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• pp.1-12
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• 2005

Feed conversion efficiency contributes directly or indirectly on the cost benefit ratio of silkworm rearing and is considered to be an important physiological criterion for evaluating the superiority of silkworm breeds/hybrids. Food intake, assimilation and conversion of indigenous as well as exotic silkworm races are well studied by many researchers. In this review, an attempt has been made to consolidate works on feed conversion aspects of indigenous and exotic silkworm races. The paper also deals with the effect of various factors viz., nutritional, environmental and feeding on food assimilation and conversion parameters of mulberry silkworm.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.607-611
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• 2016

This study was conducted to investigate the effects of different water temperatures on growth, survival, biochemical composition, and blood physiological parameters of juvenile mandarin fish Siniperca scherzeri. Feed-trained juvenile fish were subjected to four water temperatures (20, 23, 26 and 29℃) with two replicate groups. The fish were fed to apparent satiation twice daily using a formulated diet containing 55% crude protein and 6% crude lipid. After the 8-week feeding trial, survival was >96% in all groups. Weight gain and feed efficiency of fish reared at 26 and 29℃ were higher than those reared at 20℃. The protein efficiency ratio, daily feed intake, and whole body proximate composition were not affected by water temperature. These results indicate that a suitable water temperature range for optimal growth and feed efficiency of juvenile mandarin fish is 26-29℃ under these experimental conditions.

• Fisheries and Aquatic Sciences
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• v.5 no.2
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• pp.103-107
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• 2002

A 6-week feeding trial was conducted to investigate the effects of six different dietary animal protein sources on growth and body composition of olive flounder, Paralichthys olivaceus in recirculating system. White fish meal (WFM), flounder muscle (FLM), carp muscle (CM), blood meal (BM), squid liver powder (SLP) and casein (CA) were used as the main animal protein sources in the six experimental diets. Fish averaging $2.9\pm0.03g$ $(mean\pm SD)$ were distributed to each aquarium as a group of 15 fish and were fed one of the six experimental diets to each treatment of triplicate groups. After 6-week of the feeding trial, fish fed white fish meal (WFM) and flounder muscle (FLM) diets showed a significant higher weight gain $(WG\%)$ (P<0.05) than those of fish fed the CM, BM, SLP and CA diets. Fish fed BM diet showed the lowest WG among all the dietary treatments. Feed conversion ratio (FCR) and protein efficiency ratio (PER) showed the similar trend as WG. Hematocrit and hemoglobin were not affected by the dietary treatments. Fish fed the FLM and CM diets showed significant higher survival rate than those of fish fed BM diets, and there was no significant difference in survival of fish fed WFM, FLM, CM, SLP and CA diets. These results indicated that WFM and FLM are the best dietary protein sources tested in olive flounder.

• Journal of Wetlands Research
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• v.3 no.1
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• pp.75-89
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• 2001

Constructed wetlands were typically cost less to build and operate, and require less energy than standard mechanical treatment technology but they have similar performance to centralized wastewater treatment plants. Therefore, they were constructed especially many in rural areas, where are small villages but not industries. Accordingly, plantless column tests were performed to investigate the possibility on using zeolite as a filter medium of constructed wetland for the wastewater treatment. $COD_{cr}$ removal efficiency was 94.63% at hydraulic load $314L/m^2{\cdot}d$ and filtering hight 100cm filled with a zeolite mixture. This zeolite mixture consisted of 1 : 1 by volume of a zeolite in the diameter range of 0.5 to 1mm to a zeolite in the diameter range of 1 to 3mm. According, hydraulic load $314L/m^2{\cdot}d$ was considered as optimal. Three zeolite mixture were used to determine the optimal mixing ratio by volume of a zeolite(A) in the diameter range of 0.5 to 1mm to a zeolite(B) in the diameter range of 1 to 3mm diameter. 1 : 3, 1 : 1 and only B in A to B by volume were tested at hydraulic load $314L/m^2{\cdot}d$ and filtering hight 100cm. $COD_{cr}$ removal efficiency was more than 89% at mixing ratios of 1 : 3 and 1 : 1 in A to B. Removal efficiency was lower at the column filled with only B. Removal efficiency was better at filter medium filled with mixing ratio 1 : 1 in A to B than with the other mixing ratios. Thus, it was found that the mixture of mixing ratio 1 : 1 in A to B was appropriate for filter medium of constructed wetland. Removal efficiency was higher in down-flow than in up-flow, and $COD_{cr}$ and BOD were removed best in 20cm filter height near feeding area.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.2
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• pp.155-159
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• 2000

In the spring silkworm rearing period of year 1998, some nutritional aspects were studied in the Agricultural Research Station of the Komotini town in Greece, to investigate the feeding behaviour of some Bulgarian silkworm hybrids, suitable for spring rearing, during the fourth and fifth instal under the local climatic conditions. The silkworms were fed by locally cultivated Japanese Kinriu mulberry (Morus alba L.) variety leaves. Eight Bulgarian hybrids had been used, namely Vratza-53xVratza-52, Ukraine-20xVratza-53, Super 1xHessa 2, Merefa 2xVratza 35, as well as their reciprocal crosses. The studies showed out a remarkably higher feed intake and feed utilization by the hybrids Hessa 2xSuper-1, Merefa 2xVratza 35 and Vratza-52xVratza-53. The same hybrids showed an efficient food utilization by means of daily growths cocoon shell ratio and raw silk output. In terms of food to silk conversion efficiency Hessa 2xSuper-1 hybrid gave the best results. Larval stage duration for fourth and fifth instar was not affected by feed intake and utilization. All hybrids showed a good adaptation to the local environment and their feeding performance was equal to the international existing standards. All calculated parameters were found to be around the mean values of other up to date presented results and thus considered as acceptable for the needs of the local production.

• Fisheries and Aquatic Sciences
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• v.21 no.10
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• pp.30.1-30.6
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• 2018

A study of three feeding trials was conducted to investigate the dietary protein requirements of Pacific white shrimp (Litopenaeus vannamei) at three different growth stages. Six experimental diets were formulated to include increasing protein levels of 25, 30, 35, 40, 45, and 50% (designated as P25, P30, P35, P40, P45, and P50, respectively) for three feeding trials. The three feeding trials were conducted in different-sized shrimp at 0.65 g (trial 1), 4.80 g (trial 2), and 10.5 g (trial 3). Triplicate groups of shrimp were fed one of the experimental diets for 36, 42, and 48 days in trials 1, 2, and 3, respectively. In trial 1, the growth performance was not affected by the dietary protein levels. However, protein efficiency ratio was significantly higher in P30 diet compared to P40, P45, and P50 diets. In trial 2, growth rate was significantly higher in P35 diet than in P25 diet. In trial 3, the lowest growth performance was obtained in P25 diet which significantly differed from that of other experimental diets. Broken line analysis of growth data indicates that the optimal dietary level of crude protein is 34.5, 35.6, and 32.2% for small-, medium-, and large-sized (juvenile, sub-adult, and adult stages) Pacific white shrimp, respectively.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.5
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• pp.669-678
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• 2009

The reduction of excess activated sludge from petrochemical plant was investigated by the electro fenton (E-Fenton) process using electrogenerated hydroxyl radicals which lead to mineralization of activated sludge to $CO_2$, water and inorganic ions. Factors affecting the disintegration efficiency of excess activated sludge in E-Fenton process were examined in terms of five criteria: pH, $H_2O_2/Fe^{2+}$ molar ratio, current density, initial MLSS (mixed liquid suspended solids) concentration, $H_2O_2$ feeding mode. TSS total suspended solid and $TCOD_{cr}$ reduction rate increased with the increasing $H_2O_2/Fe^{2+}$ molar ratio and current density until 42 and $6.7 mA/cm^2$, respectively but further increase of $H_2O_2/Fe^{2+}$ molar ratio and current density would reduce the reduction rate. On the other hand, as expected, increasing pH and initial MLSS concentration of activated sludge decreas TSS and $TCOD_{cr}$ reduction rate. The E-Fenton process was gradually increased during first 30 minutes and then linearly proceed till 120 minutes. The optimal E-Fenton condition showed TSS reduction rate of 62~63% and $TCOD_{cr}$ (total chemical oxygen demand) reduction rate of 55~56%. Molar ratio $H_2O_2/Fe^{2+} = 42$ was determined as optimal E-Fenton condition with initial $Fe^{2+}$ dose of 5.4 mM and current density of $6.7{\sim}13.3 mA/cm^2$, initial MLSS of 7,600 mg/L and pH 2 were chosen as the most efficient E-Fenton condition.

• Nutritional Sciences
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• v.9 no.2
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• pp.92-96
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• 2006

Studies were carried out to determine the effect of feeding diet containing 5% canola oil on growth, feed efficiency, and fatty acid profile of bacon in finishing pigs and of longissimus muscle in horses fattening for meat production. In experiment 1, twenty cross-bred barrows and twenty cross-bred gilts (average weight, 80 kg) were blocked by sex and weight, and five barrows or five gilts were allotted to one of eight pens $(6.25m^2/pen)$, respectively. Four pens (two with barrows and two with gilts) randomly selected were assigned to a control diet containing 5% tallow and the remaining four pens to a diet containing 5% canola oil. The average daily weight gain, daily feed intake and feed efficiency over a 6-wk feeding period were not different (p>0.05) between the two diets, nor was backfat thickness. Fatty acid profile in bacon fat showed that the 0-3 fatty acid ($\alpha-linolenic$ acid) content in pigs fed diet containing 5% canola oil was approximately three times (P<0.01) as much as in pigs fed tallow. In experiment 2, thirty-two Jeju horses (average $weight{\pm}SE,\;244{\pm}5kg$) were blocked by sex and weight, and two horses of the same sex and similar body weight were allotted to one $(15m^2/pen)$ of eight pens. Eight pens (four with males and four with females) selected randomly were assigned to a control diet containing 5% tallow and the remaining eight pens to a diet containing 5% canola oil. The average daily weight gain, daily feed intake and feed efficiency for concentrates without roughages over a 5-month feeding period were not different (P>0.05) between the two diet groups. Fatty acid profile in the muscle fat showed that the 0-3 fatty acid (a-linolenic acid) content in horses fed diet containing 5% canola oil was approximately two times (P<0.01) that in horses fed tallow. The increased (P<0.01) 0-3 fatty acid content in pigs and horses fed canola oil decreased the ratio of n-6 to n-3 fatty acids compared to the control, indicating a significant improvement in pork and horsemeat fatty acid profile for health benefit. Our study demonstrated that feeding diet containing 5% canola oil may help produce pork and horsemeat with more health benefit, increasing their $\alpha-linolenic$ acid content without deleterious effects on growth of pigs and horses.

• Fisheries and Aquatic Sciences
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• v.5 no.2
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• pp.122-126
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• 2002

A feeding trial was conducted to determine compensatory growth of juvenile olive flounder in the spring. Five treatments of fish with 3 replicates were prepared: the control group fish (C) fed twice daily for 8 weeks, the Sl, S2, S3 and S4 fish fed for 7, 6, 5 and 4 weeks after 1, 2, 3 and 4 weeks of starvation, respectively. Survival of olive flounder was not significantly different among treatments. Weight gain of flounder in S2 was significantly (P<0.05) higher than that of fish in S3 or S4, but not significantly different from that of fish in C or Sl. The poorest weight gain was observed in fish of S4 treatment. Specific growth rate (SGR) for flounder in S2 was significantly (P<0.05) higher than that for fish in C or S4, but not significantly different from that of fish in Sl or S3. Feed intake (g/fish) was proportional to duration of days of feeding except for flounder in S2, but not significantly different among C, Sl or S2. Feed efficiency ratio (FER) and protein efficiency ratio (PER) for flounder in S2 were significantly (P<0.05) higher than for fish in C, but not significantly different from those for fish in Sl, S3 or S4. Hepatosomatic index (HSI) and condition factor (CF) for flounder in Sl, S3 and S4 were not significantly different from those for fish in C, but significantly (P<0.05) lower than S2 except for CF in Sl at the end of the experiment. Proximate composition of the whole body of flounder was not significantly different among treatments. In considering results of the experiment, juvenile olive flounder achieved compensatory growth when properly fed after starved up to 2 weeks in the spring. Compensatory growth of fish was supported by improvement in SGR, FER and PER in fish starved.

• Korean Journal of Food Science and Technology
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• v.11 no.1
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• pp.50-55
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• 1979

To study the effects of diets containing Ginseng extracts as foods, Sprague-Dawley strain rats were fed several diets containing the Ginseng extracts(Ginseng nectar, Ginseng orange juice, Ginseng drink) for 12 week. The Ginseng diets contained 555 mg or 1,110 mg of Ginseng extracts per kg of the diet. During the feeding, growth rate, feed efficiency ratio, organ weight, hematocrit value, SGOT and SGPT activity were compared with those of the control rats. As results of growth rate, feed efficiency ratio, organ weight, hematocrit value and SGPT activity showed no statistical significance between Ginseng fed animals and the controls. The experimental animals showed slightly lower SGOT activity and higher serum cholesterol than the controls did. The difference was, however, not statistically significant. No abnormalities of liver, spleen and kidney tissues were observed in the rats fed with the diets containing the Ginseng extract. As result of swimming test, a statistically significant increase of the swimming time was observed in the experimental animal groups, especially in Group V.