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Analysis of Changes in Ion Concentration with Time and Drainage Ratio under EC-based Nutrient Control in Closed-loop Soilless Culture for Sweet Pepper Plants (Capsicum annum L. 'Boogie') (EC 기준 순환식 파프리카 수경재배에서 시간 경과 및 배액율에 따른 이온농도 변화 분석)

  • Ahn, Tae-In;Shin, Jong-Wha;Son, Jung-Eek
    • Journal of Bio-Environment Control
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    • v.19 no.4
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    • pp.298-304
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    • 2010
  • Nutrient uptake by plants and drainage ratio in culture beds can affect ion balance and concentrations of nutrient solutions in electrical conductivity (EC)-based closed-loop soilless culture. This study was conducted to analyze ion concentration changes with time and drainage ratio under EC-based nutrient control in closed-loop soilless culture for sweet pepper plants (Capsicum annum L. 'Boogie'). At first experiment, ion concentrations of the nutrient solution were periodically analysed while collected drainage was being reused by mixing with fresh nutrient solution at a dilution rate of EC $2.2\;dSm^{-1}$. Changes in ion concentrations of $K^+$, $Ca^{2+}$, $Mg^{2+}$, $NO_3^-$, $SO_4^{2-}$, and $PO_4^{3-}$ were 1.13, 5.35, 0.92, 0.9, 1.10, $0.19\;meq{\cdot}L^{-1}$, respectively. Ion balance such as $K^+$ : $Ca^{2+}$ and $SO_4^{2-}$ : $NO_3^-$ were mainly affected during the recirculation of nutrient solution. At second experiment, ion concentrations and EC of drainage were compared before and after replenishment under different four drainage ratios of 7%, 16%, 39%, and 51%. Ion ratios of the recirculated nutrient solutions such as $K^+$ : $Ca^{2+}$ for cation and $SO_4^{2-}$ : $NO_3^-$ for anion were investigated. ECs of drainage decreased with increase of drainage ratio and each ion concentration showed the same trends as EC did. Ion balances in drainage with drainage ratio were a little different from each other, but each ratio could be corrected by replenishment process. The ion balance at 7% drainage ratio was closest to initial ratio and followed by 16%, 51%, and 39% in the order. Ion balance such as $K^+$ : $Ca^{2+}$ and $NO_3^-$ : $PO_4^{3-}$ were mainly affected the correction process.

A Study on the Au Recoverability from Mongolian Tailings (몽골 광미로부터 Au 회수 가능성에 관한 연구)

  • Ko, Chin-Surk;Burentogtokh, Togtokhmaa;Lee, Jong-Ju;Park, Cheon-Young
    • Korean Journal of Mineralogy and Petrology
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    • v.33 no.1
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    • pp.41-51
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    • 2020
  • The purpose of this study was to investigate the possibility of eco-friendly/efficient recovery of valuable resources, such as Au from mine tailings, which are environmental pollutants in the Mongolian mine sector. For this purpose, this study selected 4 place of mine tailings of the Mongolian mines sector and carried out mineralogy evaluation of the valuable resources in the tailings. In this study, flotation was performed to separate and concentrate valuable resources in the tailings. Microwave nitric acid leaching was used to leach the valuable resources contained in the sample and to improve the Au grade. Chloride leaching attempted to leach Au from the leaching residues. XRD analysis of the tailings samples showed that most of the samples consisted of silicate minerals. As a result of confirming the content of the element through XRF analysis, the SiO2 content was very high, the Fe2O3 content was 2.32-4.23%, and the content of PbO, CuO and ZnO components were all within 2%. As a result of flotation for the tailings samples, the recovery of Au was the highest in Bayanairag sample (95.38%). As a result of microwave nitric solution experiment on Au concentrate sample obtained by flotation, the content of Au in the microwave nitrate leaching residue increased by 12.15% from 192.72 g/ton to 216.14g/ton in Khamo sample, the highest increase was 57.58% in Bayanairag sample. TCLP tests on tailings generated after flotation showed dissolution characteristics within EPA. Chloride leaching test was performed to recover Au from solid residues. The leaching rate was 87.43-89.35% within 10 minutes. For Khamo sample, 100% Au was leached after 60 minutes of leaching time. Therefore, in order to process the tailings continuously generated in Mongolia, applying the same process as the present study is expected to effectively recover the valuable resources contained in the tailings.

Preliminary Study on the Development of a Platform for the Optimization of Beach Stabilization Measures Against Beach Erosion III - Centering on the Effects of Random Waves Occurring During the Unit Observation Period, and Infra-Gravity Waves of Bound Mode, and Boundary Layer Streaming on the Sediment Transport (해역별 최적 해빈 안정화 공법 선정 Platform 개발을 위한 기초연구 III - 단위 관측 기간에 발생하는 불규칙 파랑과 구속모드의 외중력파, 경계층 Streaming이 횡단표사에 미치는 영향을 중심으로)

  • Chang, Pyong Sang;Cho, Yong Jun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.6
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    • pp.434-449
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    • 2019
  • In this study, we develop a new cross-shore sediment module which takes the effect of infra-gravity waves of bound mode, and boundary layer streaming on the sediment transport into account besides the well-known asymmetry and under-tow. In doing so, the effect of individual random waves occurring during the unit observation period of 1 hr on sediment transport is also fully taken into account. To demonstrate how the individual random waves would affect the sediment transport, we numerically simulate the non-linear shoaling process of random wavers over the beach of uniform slope. Numerical results show that with the consistent frequency Boussinesq Eq. the application of which is lately extended to surf zone, we could simulate the saw-tooth profile observed without exception over the surf zone, infra-gravity waves of bound mode, and boundary-layer streaming accurately enough. It is also shown that when yearly highest random waves are modeled by the equivalent nonlinear uniform waves, the maximum cross-shore transport rate well exceeds the one where the randomness is fully taken into account as much as three times. Besides, in order to optimize the free parameter K involved in the long-shore sediment module, we carry out the numerical simulation to trace the yearly shoreline change of Mang-Bang beach from 2017.4.26 to 2018.4.20 as well, and proceeds to optimize the K by comparing the traced shoreline change with the measured one. Numerical results show that the optimized K for Mang-Bang beach would be 0.17. With K = 0.17, via yearly grand circulation process comprising severe erosion by consecutively occurring yearly highest waves at the end of October, and gradual recovery over the winter and spring by swell, the advance of shore-line at the northern and southern ends of Mang-Bang beach by 18 m, and the retreat of shore-line by 2.4 m at the middle of Mang-Bang beach can be successfully duplicated in the numerical simulation.

Development of dry milling suitable rice cultivar to invigorate rice processing products

  • Jeung, Ji-Ung
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.10-10
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    • 2017
  • Rice consumption has been continuously decreasing as the eating habits of Koreans have become westernized and diversified. The per capita annual rice consumption in Korea has dropped sharply from 136.4 kg in 1970 to 61.9 kg in 2016. The Korean government, therefore, has been trying to promote rice consumption by invigorating the processed food industry using rice flour. To facilitate the market for processed rice foods, it is essential to develop proper milling technology in terms of flour particle size and damaged starch content to produce high quality rice flour at competitive cost. Dry milling and wet milling are the two major processes used to produce rice flour. Although the dry milling process is relatively simple with a lower production cost, damaged starch content increases because of the high grain hardness of rice. In wet milling, the quality of rice flour is improved by reducing flour particle size as well as damaged starch content through soaking procedures. However, the production costs are high because of the additional expenses associated with the disposal of waste water, sterilization and drying of the wet flour. Recently developed technologies such as jet milling and cryogenic milling also require expensive investment and production. Therefore, developing new rice cultivars with dry milling adaptability as well as good processing properties is an important goal of rice breeding in Korea. 'Suweon 542' is a floury endosperm mutant line derived from sodium azide treatment on a high-yield, early maturing, and non-glutinous japonica rice cultivar, 'Namil'. Compared with the wild type, after dry milling process, the grain hardness of 'Suweon 542' was significantly lower because of its round and loosely packed starch granules. Also, the flour of 'Suweon 542' had significantly smaller particles and less damaged starch than 'Namil' and other rice cultivars and its particle size distribution was similar to a commercial wheat cultivar. Recently, through collaborations with nine universities and food companies, a total of 21 kinds of processed prototypes, using the dry milling flour of 'Suweon 542', were evaluated. In the production of major rice processing products, there was no significant quality difference between the flours prepared by wet milling and dry milling. Although the amount of water added to the dough was slightly increased, it was confirmed that the recipe applying the wet flour could be used without significant change. To efficiently transfer the floury endosperm characteristics of 'Suweon 542' to other commercial rice cultivars, it is essential to develop DNA marker tightly linked to the target gene. Association analysis using 70 genome-wide SSR markers and 94 F2 plants derived from 'Suweon 542'/'Milyang 23' showed that markers on chromosome 5 explained a large portion of the variation in floury grains percentage (FGP). Further analysis with an increased number of SSR markers revealed that the floury endosperm of 'Suweon 542' was directed by a major recessive locus, flo7(t), located in the 19.33-19.86 Mbp region of chromosome 5, with RM18639 explaining 92.2% of FGP variation in the F2 population. Through further physical mapping, a co-segregate and co-dominant DNA marker with the locus, flo7(t) was successfully developed, by which, thereby, breeding efficiency of rice cultivars having proper dry milling adaptability with high yield potential or useful functional materials would be improved. 'Suweon 542' maintained the early maturity of the wild type, Namil, which can be used in rice-wheat double cropping systems in Korea not only for improved arable land but also for sharing flour production facilities. In addition to the high susceptibility against major rice diseases, nevertheless, another possible drawback of 'Suweon 542' is the high rate of viviparous under prolonged rainfall during the harvesting season. To overcome susceptibility and vivipary of 'Suweon 542', the progeny lines, derived from the crosses 'Suweon 542' and 'Jopyeong', an early maturing rice cultivar with multiple resistance against rice blast, bacterial blight, and rice strip virus, and 'Heugjinju', a anthocyanin pigment containing black rice cultivar, were intensively evaluated. As the outputs, three dry milling suitable rice elite lines, 'Jeonju614', 'Jeonju615', and 'Jeonju616' were developed.

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A Study on Minimizing the Residual $^{18}F$-FDG in the Tubing Using Nitrogen Gas (FDG 합성 후 질소가스를 이용한 튜빙의 잔류 $^{18}F$-FDG 최소화를 위한 방법의 유용성)

  • Kim, Dong-Il;Park, Hoon;Seok, Jae-Dong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.1
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    • pp.8-12
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    • 2010
  • Purpose: In $^{18}F$-FDG automated synthesizer, deliver is done in automated mode after synthesis until the dispenser. After the delivery, the yield is calculated from the radioactivity which was read by the dose calibrator located in the dispenser. However, when the distance between the automated synthesizer and the dispenser is far, there are $^{18}F$-FDG residues, which results in loss of the amount of $^{18}F$-FDG. This study investigated the usefulness of a method that minimizes $^{18}F$-FDG residues. Materials and Methods: The structure of the tubing between the (TRACERlab Mx FDG; GE.) and the dispenser is that the distance is 8 m and the internal diameter is 1/16 inch. The synthesis process of The module goes through the synthesis process of trap, synthesis, delivery in the automated module. The time taken for synthesis is about 25 to 26 minutes, after which rinsing is done. However, after rinsing, as the distance of the tubing increased, there were 10~13% of $^{18}F$-FDG residues. Therefore, a method of using push syringe and $N_2$ gas in manual mode to minimize $^{18}F$-FDG residues is analyzed. Results: In manual mode, there were $^{18}F$-FDG residues of 4~5% for the push syringe, and there were $^{18}F$-FDG residues of less than 1% for the $N_2$ gas, which showed that the method using $N_2$ gas had superior usefulness. Also, there were no $^{18}F$-FDG residues in the cleaning the next day. Conclusion: The distance between the synthesizer and the dispenser needs to be reduced as much as possible, to reduce the rate of loss of $^{18}F$-FDG resulting from the distance of the tubing. However, in case the distance between the synthesizer and the dispenser has to be increased due to the system structure, using push syringe and $N_2$ gas simultaneously is a useful method for minimizing $^{18}F$-FDG residues.

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Effect of Whalakyuoleyng-dan plus Yinsamyangwui-tang on Anti-angionesis (활락효영단합인삼양위탕(活絡效靈丹合人蔘養胃湯)이 혈관신생(血管新生) 억제(抑制)에 미치는 영향(影響))

  • Ko, Ki-Wan;Park, Joon-Hyuk;Kang, Hee;Kim, Sung-Hoon;Yu, Young-Beob;Shim, Bum-Sang;Choi, Seung-Hoon;Ahn, Koo-Seok
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.7 no.1
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    • pp.77-97
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    • 2001
  • Anti-angiogenesis is one of therapies which have been high-lightened on the research of cancer treatment. Anti-angiogenesis means that new blood vessels are created from a existing capillary tube and it is a important process on metastasis and permeation when cancer is created or formed. Since angiogenesis have been under research, a complete recovery oriented treatment against cancer have been suggested blocking metastasis, delaying the growth of cancer cell, and blocking the supply of oxygen and nutritive substance through the web of blood vessels. Until now, there are several anti-angiogenesis, which have been known to the public, such as thalidomide, angiostatin, endostatin, 2-methoxyestradiol, TNP-470, and marimastat, etc. Additionally, 17 clinical testing projects about anti-angiogenesis are on the process in NCI(National Cancer Institute). Especially, TNP-470 showed effectiveness against cancer on clinical testing after finishing animal testing. Based on existing researches showing that Yinsamyangwui-tang is effective to strengthening body resistance and Whallakhyolenyng-dan effects cells on the inside of blood vessel because Whallakhyolenyng- dan restrains cell adhesion during the restraining period of a blood vessel, I tried to research the effect of Whalakhyolenyng-dan plus Yinsamyangwui-tang on angiogenesis. I made a conclusion putting into operation through using SK-Hep-1 (KCLB 30052), A549(KCLB 10185), AGS(KCLB 21739), and BCE(Bovine Capillary Endothelial Cell). Followings are the results of my experimental research: 1. According to the researching results of anti-cancer activation against cancer cell, Whallkhyoleyng dan plus Yinsamyangwui-tang decreased the number of cancer cells -- While injecting $600{\mu}g/ml$, injected groups decreased 3.1% more comparing with the contrastive group of SK-Hep-1, 49.7% more comparing with the contrastive group of A549, and 31.0% more comparing with the contrastive group of AGS. 2. According to the researching results of DNA composition effect between BCE and cancer cell, Whallakhyoleyng-dan plus Yinsamyangwui-tang reduced the rate of SK-Hep-1 synthesis inhibition by 59.1% at $600{\mu}g/ml$ intensity comparing with contrastive group; for A549, 72.6%; for AGS, 6.1%, for BCE, 28.9%. 3. According to the researching results about the effect of BCE cell to angiogenesis, angiogenesis was restrained at $400{\mu}g/ml$ intensity during 18 hours observation. 4. In the case of aortic ring assay, the half level of angiogenesis was reduced comparing with the contrastive group while injecting with $400{\mu}g/ml$ intensity; with $800{\mu}g/ml$, under 10% comparing with contrastive group; and with $1600{\mu}g/ml$, complete restrain. According to the above results, Whallakhyoleyng-dan plus Yinsamyangwui-tang was proved to have an anti-angiogenetic effects.

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Design and Fabrication for the Development of Auto Pattern Maker (자동취형기 개발을 위한 설계 및 제작)

  • Lee, Young-Il;Kim, Jung-Hee;Park, Jee-Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.3
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    • pp.231-239
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    • 2013
  • Purpose: To design and fabricate the auto pattern maker for the development. Methods: we got the necessary data, needed in design, by using CAD. Based on the these data, we fabricated the trial product for the development of the auto pattern maker. Results: The auto pattern maker were composed with combinations of many elements; pattern making assembly, control panel, frame attachment and prober unit. The pattern making assembly was comprised of the cutter, the pattern holder, pattern remover and silence cover which could minimize the sound during the cutting process. The control panel was designed to be connected and operated with the main printed circuit board. The prober could get the eye shape data by scanning of 1.8 degrees around the groove of the frame through the encoding data according to the address. After starting, scanning was carried out in two passes, i.e. one right-handed and one left-handed. Communication connector could send the eye shape data from auto pattern maker to outer system with the RS232C transmission system. By using the one-way analysis of variance, we got the error rate of cut pattern size for ${\Phi}22mm$, ${\Phi}55mm$ and ${\Phi}62mm$. Because F-value was 0.510 and p-value was 0.601, no statistically significant differences were found. Also, the mean cutting error of the auto pattern maker was 0.0274 mm. Conclusions: we could succeed in making the trial product by applying it to the development of the auto pattern maker. The role of this auto pattern maker is to find a exact required size of lens to fit the frame by measuring the frame. The acquired data are transferred to outer system for grinding and finishing with patternless process. Also, the trial product can produce pattern to fit the frame. Therefore, it was confidently expected that the optometrists could handily produce pattern to fit the frame with this trial product and dispense the ophthalmic lens because of its efficiency and convenience compared to the past.

A Study on the Post-Receptor Mechanism of Adenosine Receptor on Norepinephrine Release in the Rat Hippocampus (흰쥐 해마에서 Norepinephrine 유리에 미치는 Adenosine Receptor의 Post-Receptor 기전에 관한 연구)

  • Choi, Bong-Kyu;Kim, Do-Kyung;Yang, Kyung-Moo
    • The Korean Journal of Pharmacology
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    • v.32 no.1
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    • pp.1-11
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    • 1996
  • Since it has been reported that the depolarization-induced norepinephrine (NE) release is inhibited by activation of presynaptic $A_1-adenosine$ heteroreceptor in hippocampus, a large body of experimental data on the post-receptor mechanism of this process has been accumulated. But, the post-receptor mechanism of presynaptic $A_1-adenosine$ receptor on the NE release has not been clearly elucidated yet. Therefore, it was attempted to clarify the post-receptor mechanisms of the $A_1-adenosine$ receptor-mediated control of NE release in this study. Slices from rat hippocampus were equilibrated with $^3H-norepinephrine$ and the release of the labelled products was evoked by electrical stimulation (3 Hz, 5 $Vcm^{-1}$, 2 ms, rectangular pulses), and the influence of various agents on the evoked tritium-outflow was investigated. Adenosine, in concentrations ranging from $1{\sim}30{\mu}M$, decreased the NE release in a dose-dependent manner, without affecting the basal rate of release. The adenosine effects were significantly inhibited by 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, $2{\mu}M$), a selective $A_1-receptor$ antagonist. The responses to N-ethylmaleimide (NEM, 10 & $30{\mu}M$), a SH-alkylating agent of G-protein, were characterized by increments of the evoked NE-release and the basal release, and the adenosine effects were completely abolished by NEM pretreatment. $4{\beta}-Phorbol$ 12,13-dibutyrate (PDB, $1{\mu}M$), a specific protein kinase C (PKC) activator, increased the evoked NE release, whereas polymyxin B sulfate (PMB,0.1 mg), a PKC inhibitor, decreased the release, and the adenosine effects were inhibited by these agents. Nifedipine $(1{\mu}M)$, a $Ca^{2+}-channel$ blocker of dihydropyridine analogue, did not affect the adenosine effect. Tetraethylammonium (TEA, 3 mM) increased the evoked NE release, and inhibited the adenosine effects, but glibenclamide, a ATP dependent $K^+-channel$ blocker, did not. Finally, 8-bromo cyclic AMP (100 & $300{\mu}M$), a membrane-permeable analogue of cAMP, did not alter the NE release, but adenosine effects were inhibited by pretreatment with 8br-cAMP. These results suggest that the decrement of the evoked NE-release by $A_1-adenosine$ receptor is mediated by the C-protein, which is coupled to protein kinase C, adenylate cyclase system and TEA sensitive $K^+-channel$, and that nifedipine-sensitive $Ca^{2+}-channel$ and glibenclamide-sensitive $K^+-channel$ are not involved in this process.

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Effect of Okadaic Acids (OA) on Nuclear Maturation and Mitochondrial Activity of Hanwoo COCs during in vitro Maturation (소 난구복합체의 체외성숙시 Okadaic Acid (OA)가 핵성숙 및 Mitochondria 활성에 미치는 영향)

  • Choi S. H.;Han M. H.;Cho S. R.;Kim H. J.;Choe C. Y.;Son D. S.;Kim Y. K.;Lee M. H.;Jeoung Y. G.;Chung Y. H.
    • Journal of Embryo Transfer
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    • v.20 no.3
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    • pp.303-309
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    • 2005
  • This study was conducted to examine the effects of OA on metaphase of meiosis II and the mitochondrial activity of cytoplasm in bovine cumulus oocytes complexes(COCs) during in vitro maturation. Hanwoo COCs were collected from the slaughterhouse cow ovaries and matured in TCM199 supplemented with $0.1\%$ PVA, 0.2 uM, 2 uM, 20 uM OA for the maturation rate of OA concentration. For the maturation effects between OA and cycloheximide(CX), COCs were matured in TCM199 with 25 ug/mL CX, 25 ug/mL CX (6 hrs culture) plus 2 uM OA or 2 uM OA only at a atmosphere $5\%\;CO_2,\;95\%$ air $39^{\circ}C$ for 6, 12, 24 hrs. To evaluate the nuclear types of matured COCs, cumulus cells were removedby $0.5\%$ hyaluronidase sol. and oocytes were fixed in 1:3 acetic acid ethyl alcohol for 30 sec. and then stained with $0.1\%$ basic Fuchsin sol. For the detection of fluoriscent intensity (FI) of matures oocytes, cumulus cells were removed same as performed above and were stained with 20 nM mite tracker for 20 min. at $39^{\circ}C$. Mitochondrial activity of FI in matured oocytes was imaged by laser conforcal microscopy (Fluoview, Olympus, Japan) and were measured scanned face on 5 um from median to endpoint of oocytes. Statical analysis of nuclear types observed the three replicates was carried out with ANOVA and Fisher's protected least significant difference test using the STATVIEW program. FI of matures oocytes was compared the multiples of the least intensity among the measured oocytes. Maturing in TCM199 supplemented with $0.1\%$ PVA, 0.2 uM, 2 uM, 20 uM OA, metaphase B were showed 72.0, 50.0, 70.0, $68.8\%$, respectively and there were different significant(p<0.05). In the case of treatment with OA and CX, metaphase were $73.8\%,\;8.2\%,\;45.5\%,\;73.7\%$ in $0.1\%$ PVA-TCM199, 25 ug/mL CX, 25 ug/mL CX plus OA or 2uM OA only, respeclively. FI was revealed the increasing tendency during the process of maturation. Whereas FI in CX was decreased about 3 times compared to the other treatments of 6 hrs maturation. We conclude that OA regulates bovine COCs maturation and induces the mitochondrial activity during the process of maturation.

PROPAGATION OF GRASS CARP AND SILVIR CARP, 1971 (초어 및 백련의 종묘 생산에 관한 연구, 1971)

  • KIM In-Bae;PAIk Eui In
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.4 no.3_4
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    • pp.113-120
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    • 1971
  • In 1971, about 150,000 fingerlings of grass and silver carps were produced and distributed from the Fishculture Laboratory of Pusan fisheries College. The adults Were those transplanted from Japan in 1963. Findings during the process of this production are summarized as following : 1. Brood fish must be handled with a great care during the catching, hormone injection and maturity inspection so as the fish are not injured, otherwise, the eggs would not mature perfectly. Scale fall also affects significantly. 2. The amount of pituitary to be injected is preferable to be 2 to 3 times or more in donor's body weight to obtain good results. 3. The eggs should be spawned or stripped and inseminated as soon as mature. If the spawning is delayed the eggs become overmature and the hatching rate decreases significantly. 4. The water once used for the incubation of eggs should not be reused. The eggs under hatching process were melted away when water once used for incubation was reused. 5. A great care must be paid to keep water in quality when the net cage culture system is employed for raising fry or early fingerlings of Chinese carps. The best method to keep water in quality is to supply water in the cage continuously through a pipe or hose. 6. Heavy outbreaks of Spirogyra occured when clear well water was supplied into the cage, and a great number of fry or fingerlings were trapped or entangled resulting in a significant decrease of fish under rearing. It was prevented when moderately bloom-ed pond water was supplied into the cage. 7. Silver carp fry are usually captured and transported in the cool season because they can not be handled in the warm season owing to a high mortality, but cage cultured small size fingerlings ranging from 1.5 to 2 cm in total length are easily handled and transported even in the hot summer season, thus it enables the fish farmers to start growing them one season earlier.

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