JULIE EKASARI
Department of Aquaculture

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Evaluation of Biofloc Technology Application on Water Quality and Production Performance of Red Tilapia Oreochromis sp. Cultured at Different Stocking Densities WIDANARNI, .; EKASARI, JULIE; MARYAM, SITI
HAYATI Journal of Biosciences Vol 19, No 2 (2012): June 2012
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.4308/hjb.19.2.73

Abstract

This study evaluated the effect of biofloc technology (BFT) application on water quality and production performance of red tilapia Oreochromis sp. at different stocking densities. Three different fish densities were applied, i.e. 25, 50, and 100 fish/m3, and for each density there were Control (without external carbon input) and BFT treatments. Mixed sex red tilapia with an initial average body weight 77.89 + 3.71 g was cultured in 3 m3 concrete tanks for 14 weeks. Molasses was added on BFT treatments as the organic carbon source at a C/N ratio of 15. Control treatments of each density tested showed more fluctuated water quality parameters throughout the experimental period. The highest TAN and nitrite-nitrogen were observed in control treatment at a stocking density of 100 fish/m3 (3.97 mg TAN/L and 9.29 mg NO2-N/L, respectively). The highest total yield was observed in control treatment at the highest density treatment (43.50 kg), whereas the highest survival was obtained by BFT treatment at a density of 25 fish/m3 (97.78 + 0.77%). Total feed used in BFT was lower than that of control treatments in particular at 50 fish/m3 density (P < 0.05) suggesting that biofloc could be continuously harvested by the fish as other source of food.
Primary Nutritional Content of Bio-Flocs Cultured with Different Organic Carbon Sources and Salinity EKASARI, JULIE; CRAB, ROSELIEN; VERSTRAETE, WILLY
HAYATI Journal of Biosciences Vol 17, No 3 (2010): September 2010
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.4308/hjb.17.3.125

Abstract

Application of bio-flocs technology (BFT) in aquaculture offers a solution to avoid environmental impact of high nutrient discharges and to reduce the use of artificial feed. In BFT, excess of nutrients in aquaculture systems are converted into microbial biomass, which can be consumed by the cultured animals as a food source. In this experiment, upconcentrated pond water obtained from the drum filter of a freshwater tilapia farm was used for bio-flocs reactors. Two carbon sources, sugar and glycerol, were used as the first variable, and two different levels of salinity, 0 and 30 ppt, were used as the second variable. Bio-flocs with glycerol as a carbon source had higher total n-6 PUFAs (19.1 + 2.1 and 22.3 + 8.6 mg/g DW at 0 and 30 ppt, respectively) than that of glucose (4.0 + 0.1 and 12.6 + 2.5 mg/g DW at 0 and 30 ppt). However, there was no effect of carbon source or salinity on crude protein, lipid, and total n-3 PUFAs contents of the bio-flocs.
Microbial abundance and diversity in water, and immune parameters of red tilapia reared in bioflocs system with different fish density (25 fish/m3, 50 fish/m3, and 100 fish/m3) Agustinus, Frid; Widanarni, .; Ekasari, Julie
Jurnal Akuakultur Indonesia Vol 9, No 2 (2010): Jurnal Akuakultur Indonesia
Publisher : Jurnal Akuakultur Indonesia

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ABSTRACTThe objective of this experiment was to study microbial abundance and diversity in the water, and immune parameters of red tilapia Oreochromis sp. cultured in bioflok system with different fish stocking densities. The experiment comprised of two different factors, carbon source addition (bioflocs and control), and fish stocking density (25 fish/m3, 50 fish/m3, dan 100 fish/m3), with an experimental period of 99 days. Microbial load in water was determined biweekly, whereas immune parameters represented by fish blood profile were measured on day 0, 50, and 90. There was no significant difference in total bacteria count in the water of all treatments; there was however a tendency shown by all treatments that the microbial load in water increased along with the culture period. There were 4 genera of bacteria which particularly found in bioflok system, which are Acinetobacter sp., Corynobacterium sp., Listeria sp., dan Pseudomonas sp, and are suggested to play a role in bioflok formation. The percentage of phagocytic index of fish in bioflok system was higher than that in control, and may indicate that bioflok may stimulate the fish immune system.Keywords: bioflocs, red tilapia, bacteria, blood profile. ABSTRAKPenelitian ini bertujuan untuk mengidentifikasi kelimpahan dan keragaman jenis bakteri dalam air dan parameter imunitas ikan nila Oreochromis sp. yang dipelihara dalam sistem bioflok dengan kepadatan ikan yang berbeda. Penelitian terdiri atas dua faktor perlakuan yaitu penambahan sumber carbon (bioflok dan kontrol), dan padat penebaran ikan (25 ekor/m3, 50 ekor/m3, dan 100 ekor/m3) dengan lama waktu pemeliharaan ikan selama 99 hari. Kelimpahan bakteri diukur setiap 2 minggu sekali selama masa pemeliharaan. Parameter imunitas meliputi gambaran darah diukur dengan pengambilan contoh darah yang dilakukan pada tiga ekor ikan pada hari ke 0, 50, dan 99. Kelimpahan bakteri pada semua perlakuan pada setiap titik pengamatan tidak menunjukkan perbedaan yang nyata. Semua perlakuan menunjukkan kecenderungan peningkatan kelimpahan bakteri seiring dengan masa pemeliharaan. Terdapat 4 genus bakteri yang hanya ditemukan pada kolam bioflok yaitu Acinetobacter sp., Corynobacterium sp., Listeria sp., dan Pseudomonas sp yang diduga berperan dalam pembentukan bioflok. Persentase indeks fagositik pada ikan dengan perlakuan bioflok lebih tinggi dibanding kontrol, yang mengindikasikan peran bioflok sebagai stimulus sistem imun.Kata kunci: bioflok, nila merah, bakteri, gambaran darah.
Bacterial quorum sensing and the role of algae in bacterial diseases control in aquaculture Wiyoto, .; Ekasari, Julie
Jurnal Akuakultur Indonesia Vol 9, No 2 (2010): Jurnal Akuakultur Indonesia
Publisher : Jurnal Akuakultur Indonesia

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Bacterial disease is one of the most common diseases in aquaculture practices which have a significant impact. Several researches noted that pathogenicity of a certain bacteria can be determined by its quorum sensing activity. Quorum sensing is a communication process of a certain bacteria with the same or different species of bacteria which involves the releasing and capturing of signal molecule to and from the environment. This activity will activate a certain target gene which further resulted in the expression of a phenotype by the bacteria. With regard to this characteristic, one of the methods to control bacterial diseases is by quorum sensing disruption. Several species of algae, both micro and macro, have been found to be able to intervense bacterial quorum sensing and thus can be used as an alternative in bacterial disease control.    Key words: quorum sensing, bacterial disease, aquaculture, algae  Abstrak Penyakit bakteri adalah salah satu penyakit yang paling umum dalam akuakultur dengan dampak yang cukup signifikan. Beberapa penelitian menunjukkan bahwa tingkat patogenitas suatu bakteri salah satunya ditentukan oleh aktivitas kuorum sensing bakteri. Kuorum sensing bakteri merupakan suatu proses komunikasi yang dilakukan oleh bakteri dengan bakteri lainnya baik yang sejenis maupun berlainan jenis yang berupa pelepasan dan penangkapan molekul sinyal menuju dan dari lingkungan sekitar bakteri tersebut. Aktivitas inilah yang akan menentukan ekspresi suatu gen target seperti patogenitas, sehingga salah satu metode yang dapat digunakan dalam mengendalikan penyakit yang disebabkan oleh bakteri adalah dengan mengganggu aktivitas kuorum sensing bakteri. Beberapa jenis alga, baik mikro maupun makro, diketahui dapat mengintervensi aktivitas kuorum sensing, dan dapat menjadi salah satu alternatif bagi pengendalian penyakit bakterial. Kata-kata kunci: kuorum sensing, penyakit bakterial, akuakultur, alga
Sex Reversal on Congo Tetra Fish (Micraleptus intterruptus ) Larvae Arfah, Harton; Alimuddin, .; Sumantadinata, K.; Ekasari, Julie
Jurnal Akuakultur Indonesia Vol 1, No 2 (2002): Jurnal Akuakultur Indonesia
Publisher : Jurnal Akuakultur Indonesia

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Abstract

Experiment was performed to assess the effect of 17a-methyltestosterone (MT) treatment on Congo tetra fish larvae.  To evaluate the optimal pattern of MT treatment, three different treatments were administrated.  Three months old larvae were submerged in three different doses of MT; 1, 2 and 4 mg/l.  These studies showed that the highest percentage of male fish was obtained by 4 mg/l MT treatment, 87,17%.  The 2 mg/l and 1 mg/l MT treatments obtained 77,53% and 69,86% male respectively, two times higher than control, 38,96%.  On the other hand, the 4 mg/l MT treatment also resulted the highest percentage of hermaphrodite fishes, 17,58%.  The highest survival rate was shown by 1 mg/l MT treatment, 62,77% and the lowest was shown by the 4 mg/l MT treatment, 47,20%.  The highest rate of fish length and weight was shown by the 4 mg/l MT treatment, 4,4 cm and 1,65 gram respectively.  These findings suggest that MT treatment offers an advantage in growth of  tetra Congo larvae. Key word :  Sex reversal, methyltestosterone, Congo tetra fish, Micraleptus intterruptus.   ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh perendaman larva di dalam larutan hormon 17a-metiltestosteron pada dosis 1, 2 dan 4 mg/l larutan.  Persentase tertinggi ikan jantan dihasilkan  oleh perlakuan 4 mg/l, yaitu 87,17%.  Perlakuan 2 mg/l dan 1 mg/l masing-masing menghasilkan 77,53% dan 69,86% sedangkan kontrol menghasilkan 38,96% jantan.  Efek lain dari perlakuan MT ini adalah hermafroditisme.  Perlakuan 4 mg/l menghasilkan persentase hermafrodit tertinggi yaitu 17,58%, sedangkan pada kontrol kelangsungan hidup tertinggi diperoleh pada perlakuan 1 mg/l (62,77%) dan terendah pada perlakuan 4 mg/l (47,20%).  Hasil tersebut menunjukkan adanya pengaruh dosis hormon terhadap kelangsungan hidup ikan.  Pengukuran bobot dan panjang ikan pada setiap perlakuan menunjukkan nilai tertinggi dihasilkan oleh perlakuan 4 mg/l  yaitu 1,65 gram dan 4,40 cm.  Hal ini diduga bahwa hormon MT merangsang pula pertumbuhan ikan. Kata kunci :  Pergantian kelamin, metiltestosteron, ikan tetra Kongo, Micraleptus intterruptus.
Bioflocs Technology: Theory and Application in Intensive Aquaculture System Ekasari, Julie
Jurnal Akuakultur Indonesia Vol 8, No 2 (2009): Jurnal Akuakultur Indonesia
Publisher : Jurnal Akuakultur Indonesia

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Abstract

Bioflocs technology (BFT) is one of the developing technology in aquaculture which aimed to improve water quality and to enhance nutrient utilization efficiency. This technology is mainly based on the conversion of inorganic nitrogen in particular ammonia by heterotrophic bacteria into microbial biomass which further can be consumed by aquaculture organisms. The objective of this review is to discuss various aspect of BFT application in aquaculture including bioflocs formation process, technical requirement, bioflocs nutritional content and characterization techniques. Keywords: bioflocs, nitrogen, heterotrophic bacteria, ammonia, C/N ratio   ABSTRAK Teknologi bioflok (BFT) merupakan salah satu teknologi yang saat ini sedang dikembangkan dalam akuakultur yang bertujuan untuk memperbaiki kualitas air dan meningkatkan efisiensi pemanfaatan nutrient. Teknologi ini didasarkan pada konversi nitrogen anorganik terutama ammonia oleh bakteri heterotrof menjadi biomassa mikroba yang kemudian dapat dikonsumsi oleh organisme budidaya. Tujuan penulisan makalah ini adalah untuk memaparkan berbagai aspek dalam BFT termasuk proses pembentukan bioflok, persyaratan teknis, kandungan nutrisi bioflok dan teknik karakterisasinya. Kata kunci: bioflok, nitrogen, bakteri heterotrof, ammonia, rasio C/N
Quality evaluation of fermented products of various local agroindustrials by-products: the effect on digestibility and growth performance of common carp juvenile Suprayudi, Muhammad Agus; Edriani, Gebbie; Ekasari, Julie
Jurnal Akuakultur Indonesia Vol 11, No 1 (2012): Jurnal Akuakultur Indonesia
Publisher : Jurnal Akuakultur Indonesia

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The aim of this research was evaluating the quality and digestibility of fermented local feedstuff as well as its effect on growth performance of common carp Cyprinus carpio juvenile. The local feedstuffs tested in this experiment were kapok seed, cassava peel, copra, rubber seed, and palm kernel meal. The previously milled feedstuff was fermented with instant yeast Saccharomyces cerevisiae with a dose of 0.9% w/w and incubated for 24 hours. Following this, the fermented feedstuffs were dried, mixed with reference diet with a ratio of 3:7 and supplemented with 0.5% Cr2O3 as digestibility test indicator. Common carp juveniles with an initial average body weight of 14,11±1,28 g were cultured for 30 days. Fish feces were collected since the 6th day of culture, and followed by laboratory analyses. The results show that fermentation could increase the crude protein content of feedstuff with a range of 16.85‒31.11%, and decrease crude fiber with a range of 2.45‒31.65% with the exception of copra. Furthermore, fermentation also increased the feed digestibility including protein, energy, and total digestibility by the tested fish, as it is shown that the use of fermented feedstuffs may increase protein digestibility 3.88‒11.73%, 2,21‒10,24%, and 3,63‒72,37%. Finally, it can be concluded that fermentation can increase the digestibility of feed with local ingredients by common carp juvenile.   Keywords: fermentation, digestibility, local materials, common carp
The effectiveness of sheep rumen liquor enzyme addition on the reduction of cocoa-pod husk meal fiber content and its digestibility in tilapia diet Jusadi, Dedi; Ekasari, Julie; Kurniansyah, Azis
Jurnal Akuakultur Indonesia Vol 12, No 1 (2013): Jurnal Akuakultur Indonesia
Publisher : Jurnal Akuakultur Indonesia

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ABSTRACT Two experiments were conducted to evaluate the effect of sheep rumen liquor enzyme addition on the reduction of cocoa-pod husk meal (CPHM) fiber content, and the digestibility of hydrolyzed CPHM for tilapia Oreochromis niloticus. In the first trial, sheep rumen liquor enzyme was added with various concentration, i.e. 0, 50, 100 and 150 mL/kg CPHM with three different incubation periods, namely 0, 12, and 24 hours. In the second trial, digestibility was determined by the addition of Cr2O3 as the indicator in both reference and experimental diets, i.e. feed with hydrolyzed CPHM and unhydrolyzed CPHM. Tilapia with an average body weight of 3.86±0.44 g were stocked at a density of 15 fish/aquarium and were maintained for 15 days. In the first trial, CPHM hydrolyzed with 150 mL/kg and incubated for 12 and 24 hour showed the lowest crude fiber content (21.38% and 21.67%). Apparent digestibility coefficient of hydrolyzed CPHM was 33.95%, which was higher than unhydrolyzed CPHM (10.97%). According to the results in these experiment, it can be concluded that sheep rumen liquor enzyme addition was effective to decrease crude fiber content of CPHM and improve the apparent digestibility coefficient of CPHM for tilapia diet. Keywords: sheep rumen liquor enzyme, cocoa-pod husk meal, digestibility, tilapia  ABSTRAK Dua tahap penelitian dilakukan untuk mengevaluasi penambahan enzim cairan rumen domba dalam menurunkan kandungan serat kasar kulit buah kakao (KBK) dan mengevaluasi ketercernaan KBK yang telah dihidrolisis dengan enzim cairan rumen domba dalam pakan ikan nila Oreochromis niloticus. Pada penelitian tahap satu, enzim cairan rumen domba ditambahkan dengan konsentrasi yang berbeda yaitu 0, 50, 100, dan 150 mL/kg KBK dengan lama inkubasi yang berbeda yaitu 0, 12, dan 24 jam. Pada penelitian tahap dua, nilai ketercernaan ditentukan dengan menggunakan indikator Cr2O3 yang ditambahkan ke dalam pakan acuan dan pakan perlakuan, yaitu pakan dengan penambahan KBK yang telah dihidrolisis dengan dosis terbaik pada penelitian tahap satu (KBKe) dan kulit buah kakao tanpa hidrolisis (KBK). Ikan nila yang digunakan mempunyai bobot rata-rata 3,86±0,44 g ditebar dengan kepadatan 15 ekor/akuarium dan dipelihara selama 15 hari. Hasil penelitian tahap satu menunjukkan hidrolisis KBK dengan menggunakan cairan rumen 150 mL/kg dan lama waktu inkubasi 12 jam dan 24 jam mempunyai nilai serat kasar KBK terendah yaitu sebesar 21,38% dan 21,67%. Sedangkan pada uji ketercernaan terlihat bahwa nilai ketercernaan bahan KBKe lebih tinggi (33,95%) dibandingkan dengan KBK (10,97%). Dengan demikian dapat disimpulkan bahwa penambahan enzim cairan rumen domba dapat menurunkan kandungan serat kasar kulit buah kakao dan meningkatkan ketercernaan kulit buah kakao pada pakan ikan nila. Kata kunci: enzim cairan rumen domba, kulit buah kakao, ketercernaan, ikan nila
Nursery Culture Performance of Litopenaeus vannamei with Probiotics Addition and Different C/N Ratio Under Laboratory Condition WIDANARNI, .; YUNIASARI, DEBY; SUKENDA, .; EKASARI, JULIE
HAYATI Journal of Biosciences Vol 17, No 3 (2010): September 2010
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.4308/hjb.17.3.115

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Application of bioflocs technology and probiotics has improved water quality and production of Pacific white shrimp (Litopenaeus vannamei) culture. This experiment was to verify the effect of probiotic bacteria addition and different carbon:nitrogen (C:N) ratio on water quality and performance of Pacific white shrimp nursery culture. Nursery culture was carried out for 25 days in an aquarium under laboratory condition with stock density of one Post-Larvae (PL) (poslarval) per liter (24 PL/aquarium) of PL16 shrimp. Different C:N ratio resulted a significant difference on shrimp production performance. Treatment of 10 C:N ratio demonstrated the best shrimp growth (20.37 + 0.48% per day in weight and 6.05 + 0.41% per day in length), harvesting yield (1180 + 62 g/m3) and feed efficiency (121 + 6%). There was however no significant difference observed between treatments in water quality.
The growth performance and resistance to salinity stress of striped catfish Pangasius sp. juvenile in biofloc system with different feeding rates Meritha, Wellya Wichi; Suprayudi, Muhammad Agus; Ekasari, Julie
Jurnal Akuakultur Indonesia Vol 17, No 2 (2018): Jurnal Akuakultur Indonesia
Publisher : ISSA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19027/jai.17.2.113-119

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ABSTRACTThis study aimed to evaluate the growth performance and resistance to salinity stress of striped catfish juvenile reared in biofloc with different feeding rate (FR). The treatments applied in this study were rearing the fish in biofloc with FR 5% and 8% of biomass per day, and rearing the fish with a FR of 8% per day without biofloc system as the control. The fish with an initial average length of 1.81 ± 0.20 cm were stocked in 9 units of  50 L aquaria with density of 40 ind/aquaria (800 ind/m3) for 15 days rearing period. In biofloc systems, the addition of tapioca as a source of organic carbon was done every day with an estimated C/N ratio of 10. No water exchange was done in biofloc systems, whereas regular water exchange was applied in the control. Results of the experiment showed that survival was not significantly different amongst treatments (P>0.05).  However, the specific growth rate of the fish in biofloc system with a FR of 8% per day showed the highest value and was significantly different from other treatments (P<0.05). Fish reared in biofloc system tend to have lower feed conversion ratios (FCRs) than the control. The lowest FCR was found in fish reared in biofloc system with 5% FR and significantly lower than control (P<0.05).  Salinity stress test was conducted by soaking 15 juveniles in water with a salinity of 20 g/L for an hour. The survival of fish after salinity stress test were significantly higher for fish reared in bifloc system than control (P<0.05). These data showed that rearing striped catfish juvenile in biofloc system could reduce FCR, increase the growth, and robustness of fish. Keywords: biofloc, feeding rate, growth, salinity stress test, striped catfish  ABSTRAKPenelitian ini bertujuan untuk mengevaluasi kinerja pertumbuhan dan ketahanan benih ikan patin terhadap stres salinitas yang dipelihara dalam sistem bioflok dengan tingkat pemberian pakan (FR) berbeda. Perlakuan yang terdapat dalam penelitian ini adalah benih patin yang dipelihara dalam sistem bioflok dengan FR 5% dan 8% per hari, dan pemeliharaan benih dengan FR 8% per hari tanpa penambahan sumber karbon sebagai kontrol. Benih patin dengan panjang rata-rata awal 1,81 ± 0,20 cm dipelihara dalam 9 unit akuarium dengan volume air 50 L dan kepadatan 40 ekor/akuarium (800 ekor/m3) selama 15 hari. Pada sistem bioflok, penambahan tapioka sebagai sumber karbon dilakukan setiap hari dengan C/N 10. Pada sistem bioflok tidak dilakukan pergantian air, sedangkan pada kontrol dilakukan pergantian air. Kelangsungan hidup ikan tidak berbeda nyata antar perlakuan. Namun, tingkat pertumbuhan spesifik ikan dalam sistem bioflok dengan FR 8% per hari menunjukkan nilai tertinggi dan berbeda nyata antar perlakuan (P<0,05). Benih yang dipelihara pada sistem bioflok memiliki rasio konversi pakan (FCR) yang lebih rendah dibandingkan kontrol, namun tidak terdapat perbedaan yang signifikan antara perlakuan bioflok (P>0,05). Uji stres salinitas dilakukan dengan merendam 15 ekor benih patin pada air dengan salinitas 20 g/L selama satu jam. Kelangsungan hidup setelah uji stres salinitas dari benih yang dipelihara di bioflok secara signifikan lebih tinggi dibandingkan kontrol (P<0,05). Hasil penelitian menunjukkan bahwa pemeliharaan benih patin pada sistem bioflok dapat menurunkan FCR, dan meningkatkan pertumbuhan dan ketahanan ikan terhadap stres salinitas. Kata kunci: bioflok, feeding rate, pertumbuhan, uji stres salinitas, ikan patin