scholarly journals The Growth and Survival of The European lobster (Hommarus gammarus) Larvae in Pseudo-Green Water and Clear Water Under Low Density Conditions

2021 ◽  
Author(s):  
Umur ÖNAL ◽  
Hakan BAKİ
Keyword(s):  
Green Water ◽  
Low Density ◽  
Clear Water ◽  
Growth And Survival ◽  
European Lobster

scholarly journals Can turbid water and refuges with aquatic macrophytes increase the survival and growth of Brycon amazonicus larvae?

2021 ◽  
Vol 10 (15) ◽  
pp. e227101522737
Author(s):  
Joana Paula de Souza Cornélio ◽  
Luís Gustavo Tavares Braga ◽  
Marle Angélica Villacorta-Correa
Keyword(s):  
Aquatic Macrophytes ◽  
Aquatic Organisms ◽  
Fish Farming ◽  
Green Water ◽  
Clear Water ◽  
Initial Development ◽  
Turbid Waters ◽  
Randomized Design ◽  
Survival And Growth ◽  
Completely Randomized Design

The productivity of aquatic organisms and higher concentration of suspended solids that occur in areas flooded by Whitewater Rivers and the presence of aquatic macrophytes are conducive to the initial development of matrinxã (Brycon amazonicus). The objective of this study was to evaluate whether turbid waters and refuges with aquatic macrophytes improve the survival and growth of the larvae of Brycon amazonicus, a species of great interest in Amazonian fish farming. For this, two experiments were conducted using a completely randomized design and with four replicas per treatment up to 120 hours after hatching (HAH), In experiment I: Brycon amazonicus larvae at 24 HAH were subjected to three treatments with different types of water: clear water (CW); clayey water (AW) and green water (GW). Experiment II: larvae with 24 HAH were maintained in clear water (CW); clear water with refuge (CWR); green water (GW); green water with refuge (GWR); clayey water (AW) and clayey water with refuge (AWR). Experiment I showed that clayey water, followed by green water, increased the survival of larvae (73.92 and 54.32%). Growth was best in larvae maintained in green water. In experiment II, the use of aquatic macrophytes did not influence the survival and growth of the larvae. Thus, we suggest the use of turbid (clayey and green) waters without refuge to increase the survival and growth of Brycon amazonicus larvae.

scholarly journals PENGARUH FREKUENSI PEMBERIAN Moina sp. SEBAGAI PAKAN AWAL PADA PEMELIHARAAN LARVA IKAN GABUS Channa striata DENGAN SISTEM AIR HIJAU

2018 ◽  
Vol 13 (3) ◽  
pp. 239 ◽  
Author(s):  
Adang Saputra ◽  
Dedi Jusadi ◽  
Muhammad Agus Suprayudi ◽  
Eddy Supriyono ◽  
Mas Tri Djoko Sunarno
Keyword(s):  
High Mortality ◽  
Fish Larvae ◽  
Water System ◽  
Green Water ◽  
Feeding Frequency ◽  
Growth And Survival ◽  
Chlorella Sp ◽  
Randomized Design ◽  
Channa Striata

Ikan gabus Channa striata merupakan salah satu komoditas ikan air tawar yang memiliki nilai ekonomis tinggi. Kendala dalam pengembangan budidaya ikan gabus adalah tingginya tingkat kematian pada stadia pemeliharaan larva. Tingginya kematian pada stadia larva karena kecukupan jumlah pakan dan nutrisi pakan awal yang tidak optimum. Tujuan percobaan adalah menentukan frekuensi pemberian Moina sp. yang tepat sebagai pakan awal pada pemeliharaan larva ikan gabus pada sistem air hijau (dengan menambahkan Chlorella sp.). Penelitian dirancang dengan rancangan acak lengkap. Perlakuan yang diberikan adalah frekuensi pemberian Moina sp. per hari sebagai pakan awal: A. enam kali tanpa pemberian Chlorella sp. (kontrol), B. enam kali + Chlorella sp., C. empat kali + Chlorella sp., dan D. dua kali + Chlorella sp. Hasil penelitian menunjukkan pemberian pakan awal dari jenis Moina sp. pada pemeliharan larva ikan gabus pada sistem air hijau dengan frekuensi pemberian dua, empat, dan enam kali dalam sehari memberikan performa sintasan (93,42%-94,29%) dan pertumbuhan tidak berbeda secara nyata (P>0,05). Frekuensi pemberian Moina sp. sebanyak dua kali sehari merupakan perlakuan yang efektif untuk sintasan dan pertumbuhan larva ikan gabus pada pemeliharaan dengan sistem air hijau.Snakehead fish Channa striata is one of the highly-valued freshwater fish commodity. However, its aquaculture development is hampered by a high mortality during larval stage rearing. This high mortality is suspected to be caused by insufficient quantity and quality of food. The purpose of this study was to determine the appropriate feeding frequency using Moina sp. as an initial food for snakehead fish larvae reared in a green water system (Chlorella sp.). A completely randomized design was arranged for this experiment where the treatments consisted of different feeding frequencies of Moina sp. given to the larvae as follows: A) six times a day without the addition of Chlorella sp. (control); B) six times a day with the addition of Chlorella sp.; C) four times a day with the addition of Chlorella sp.; and D) two times a day with the addition of Chlorella sp. The results of the experiment showed that the survival rate (93.42%- 94.29%) and growth of the larvae reared in the green water system with were not significantly different (P>0.05). However, this study suggested that feeding frequency of two times per day was sufficient to support an optimum growth and survival of snakehead larvae reared in a green water system.

scholarly journals Growth, behaviour, and digestive enzyme activity in larval Atlantic cod (Gadus morhua) in relation to rotifer lipid

2006 ◽  
Vol 63 (2) ◽  
pp. 275-284 ◽  
Author(s):  
Kelly O'Brien-MacDonald ◽  
Joseph A. Brown ◽  
Christopher C. Parrish
Keyword(s):  
Enzyme Activity ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Digestive Enzyme ◽  
Green Water ◽  
Digestive Enzyme Activity ◽  
Activity Levels ◽  
Growth Behaviour ◽  
Live Prey ◽  
Growth And Survival

Abstract Atlantic cod (Gadus morhua) show great potential for aquaculture, but much is unknown about their digestive capacity and efficiency. An integrated experiment was performed on cod larvae to investigate the variability in digestive development in response to the quantity of lipid in the rotifer enrichment. Survival, growth, behaviour, and digestive enzyme data from hatching to metamorphosis [0–450 dd (degree-days)] were measured. Four treatments were used in triplicate: high lipid rotifer enrichment (HLRE), low lipid rotifer enrichment (LLRE), green water, and unfed. Swimming activity and attacks (captures + misses) on prey were higher in the HLRE group at 100 dd than in other treatments, and this difference increased thereafter. There was no difference in digestive enzyme activity between the unfed and greened treatments, while the LLRE larvae had lower activity levels than larvae fed HLRE by 100–150 dd for all enzymes assayed. The larvae in the unfed and green water treatments did not survive past 100 dd. All the LLRE cod had died by 250 dd. Results suggest that a higher quantity of lipid in the rotifer enrichment will not only promote better growth and survival in Atlantic cod larvae but appears to provide more energy, allowing larvae to capture more live prey.

scholarly journals Rearing of Freshwater Fish ‘Catla catla (Hamilton, 1822)’ Spawn to Fry in Green Water System with Harvested Rain Water in Cement Tanks

2017 ◽  
Vol 5 (1) ◽  
pp. 66-73
Author(s):  
B. P Bhoye ◽  
B. R. Chavan ◽  
V. R. Sadavarte ◽  
H. B. Dhamagaye ◽  
M. T. Kamble ◽  
...  
Keyword(s):  
Freshwater Fish ◽  
Average Length ◽  
Water System ◽  
Stocking Density ◽  
Ammonia Nitrogen ◽  
Rain Water ◽  
Green Water ◽  
Catla Catla ◽  
Growth And Survival ◽  
Length Gain

The present study on the effect of green water system with harvested rain water on growth performance of freshwater fish Catla catla. Spawn of Catla with an initial length 5.50±0.04 mm and weight 10.99±0.30 mg were stocked at the rate of 6, 8, 10 and 12 no.l-1 in cement tanks (2x1x1m). The green water system containing live phytoplankton viz., Chlorophyta, Cyanophyta and zooplankton viz., Rotifera, Cladocera, Copepoda and Protozoa were was used. The results of the study indicated that the maximum average length gain was (357.89±3.08%), weight gain (779.53±18.03%), specific growth rate (5.56±0.08%) and survival (45.20±0.13%) and were recorded significantly (P<0.05) at stocking density of 6 spawn l-1 as compared to the other stocking densities. The growth of spawn to fry was observed to decrease with increase in the stocking density. Observations on the water quality revealed that the dissolved oxygen value decreased with an increased stocking density. Whereas, the value of ammonia-nitrogen, nitrite-nitrogen, and nitrate-nitrogen increased with the increase in the stocking density. The study showed that better growth and survival of Catla catla spawn to fry stage with stocking density of 6 spawn l-1 reared for a period of16 days in cement tank. The overall results of this study indicated that green water system with harvested rain water has a potential for rearing fish seeds.

Production of marine tilapia in a green-water, closed system in Senegal: the integrated recycling aquaculture system.

2020 ◽  
Author(s):  
Nicolas de Wilde ◽  
Sylvain Gilles
Keyword(s):  
Wastewater Treatment ◽  
Energy Savings ◽  
Brachionus Plicatilis ◽  
Water Levels ◽  
Green Water ◽  
Clear Water ◽  
Aquaculture System ◽  
Suspended Growth ◽  
Growth System ◽  
Sarotherodon Melanotheron

Abstract The Integrated Recycling Aquaculture System (Système Aquacole à Recyclage Intégral, or SARI) is a photosynthetic suspended growth system that combines rearing of euryhaline tilapia (Sarotherodon melanotheron heudelotii) with a recirculating brackish planktonic wastewater treatment. Compared with classical clear-water closed recirculating systems, it brings important advantages in terms of fresh water and energy savings, and biosecurity, by limiting invasion and growth of pathogens. A prototype of SARI was installed and studied at the IRD Centre at Mbour, Senegal. When reared in intensive or semi-intensive conditions, S. melanotheron heudelotii enhances production of green algae, Chlorella spp., which reduce the water levels of ammonia from fish excretion. The algae population is controlled by the rotifer, Brachionus plicatilis, which is also fed to reared fingerlings.

Application of Improved Voltage Compensation in the SEM to Imaging of Organic Materials

1973 ◽  
Vol 31 ◽  
pp. 444-445
Author(s):  
P.J. Killingworth ◽  
M. Warren
Keyword(s):  
Electron Beam ◽  
Organic Materials ◽  
Operating Parameters ◽  
Low Density ◽  
Beam Diameter ◽  
Incident Electron Beam ◽  
Specimen Material ◽  
Voltage Compensation ◽  
Selection Of ◽  
Scanning Electron

Ultimate resolution in the scanning electron microscope is determined not only by the diameter of the incident electron beam, but by interaction of that beam with the specimen material. Generally, while minimum beam diameter diminishes with increasing voltage, due to the reduced effect of aberration component and magnetic interference, the excited volume within the sample increases with electron energy. Thus, for any given material and imaging signal, there is an optimum volt age to achieve best resolution.In the case of organic materials, which are in general of low density and electric ally non-conducting; and may in addition be susceptible to radiation and heat damage, the selection of correct operating parameters is extremely critical and is achiev ed by interative adjustment.

Quantitative defect studies in semiconductor TEM samples prepared by low angle ion milling

1995 ◽  
Vol 53 ◽  
pp. 512-513
Author(s):  
L. Mulestagno ◽  
J.C. Holzer ◽  
P. Fraundorf
Keyword(s):  
Sample Preparation ◽  
Milling Time ◽  
High Density ◽  
Low Density ◽  
Ion Milling ◽  
High Quality ◽  
Variable Angle ◽  
Major Disadvantage ◽  
Induced Defects

Due to the wealth of information, both analytical and structural that can be obtained from it TEM always has been a favorite tool for the analysis of process-induced defects in semiconductor wafers. The only major disadvantage has always been, that the volume under study in the TEM is relatively small, making it difficult to locate low density defects, and sample preparation is a somewhat lengthy procedure. This problem has been somewhat alleviated by the availability of efficient low angle milling.Using a PIPS® variable angle ion -mill, manufactured by Gatan, we have been consistently obtaining planar specimens with a high quality thin area in excess of 5 × 104 μm2 in about half an hour (milling time), which has made it possible to locate defects at lower densities, or, for defects of relatively high density, obtain information which is statistically more significant (table 1).

Intralysosomal Accumulation of Colloidal Gold-Low Density Lipoprotein Conjugates in Chloroquine-Treated Fibroblasts

1985 ◽  
Vol 43 ◽  
pp. 546-547 ◽  
Author(s):  
Dean A. Handley ◽  
Cynthia M. Arbeeny ◽  
Larry D. Witte
Keyword(s):  
Colloidal Gold ◽  
Cultured Cells ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Coated Vesicle ◽  
Low Density ◽  
Cholesterol Esters ◽  
Cultured Fibroblasts ◽  
Surface Receptors ◽  
Ldl Particles

Low density lipoproteins (LDL) are the major cholesterol carrying particles in the blood. Using cultured cells, it has been shown that LDL particles interact with specific surface receptors and are internalized via a coated pit-coated vesicle pathway for lysosomal catabolism. This (Pathway has been visualized using LDL labeled to ferritin or colloidal gold. It is now recognized that certain lysomotropic agents, such as chloroquine, inhibit lysosomal enzymes that degrade protein and cholesterol esters. By interrupting cholesterol ester hydrolysis, chloroquine treatment results in lysosomal accumulation of cholesterol esters from internalized LDL. Using LDL conjugated to colloidal gold, we have examined the ultrastructural effects of chloroquine on lipoprotein uptake by normal cultured fibroblasts.

ALCHEMI of B2-Ordered Fe50Al45Me5 alloys

1996 ◽  
Vol 54 ◽  
pp. 548-549
Author(s):  
Ian M. Anderson
Keyword(s):  
Room Temperature ◽  
Iron Aluminide ◽  
Low Density ◽  
Intermetallic Alloys ◽  
Practical Applications ◽  
Alloying Additions ◽  
Site Distribution ◽  
Good Corrosion Resistance ◽  
Room Temperature Ductility ◽  
The Matrix

B2-ordered iron aluminide intermetallic alloys exhibit a combination of attractive properties such as low density and good corrosion resistance. However, the practical applications of these alloys are limited by their poor fracture toughness and low room temperature ductility. One current strategy for overcoming these undesirable properties is to attempt to modify the basic chemistry of the materials with alloying additions. These changes in the chemistry of the material cannot be fully understood without a knowledge of the site-distribution of the alloying elements. In this paper, the site-distributions of a series of 3d-transition metal alloying additions in B2-ordered iron aluminides are studied with ALCHEMI.A series of seven alloys of stoichiometry Fe50AL45Me5, with Me = {Ti, V, Cr, Mn, Co, Ni, Cu}, were prepared with identical heating cycles. Microalloying additions of 0.2% B and 0.1% Zr were also incorporated to strengthen the grain boundaries, but these alloying additions have little influence on the matrix chemistry and are incidental to this study.

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