Application of Artificial Feed with Different Protein Content on Blacksaddled Coral Grouper Plectropomus Laevis Nursery

Blacksaddled coral grouper Plectropomus laevis is an export commodity and possess high economic value in Asian markets, but the wild population is already threatened. The purpose of this study was to determine the best food for improving growth and survival rate. The nursering were conducted using 9 fiberglass tanks with 1 m3 of volume for 6 month, with three treatment and 3 replicates. Three different foods were used as treatments, i.e.: Local commersial pellet with crude protein content 50% (A), im-port commersial pellet with cure protein content 55% (B) and trash fish (sardine) (C). The initial size of blacksaddled coral grouper seed were 2.5 cm total lengths (TL), 0.45 g body weight (BW). The stocking density of fry was reared at 250 fish per m3. A complete random design was used as an experiment design. Data was analysed using ANOVA statistics. Feeding times were twice a day at 08.00 and 15.00 local time; with dose at satiation. The samplings of fry were conducted every 15 day to measure of survival rate (SR), TL and BW. On the end of experiment was calculated economic ana-lized (BC ratio). The result showed that there was significant different (P<0.05) among treatments for SR and growth rate (GR). The better SR and GR was at treatment B with SR 96.5%, and GR 0.75g/day followed by treatment C (SR 90.5%: GR 0.54g/day) and treatment A (SR 81.5%: GR 0.42g/ day. The food conversion ratio was 1.15 in treatment A, 1.02 in B and 4.81 (wet weight) in C. From economic analized showed that the best BC ratio was in pellet 55% protein (B), followed by trash fish (C) and pellet 50% protein (A) with BC ratio of 1.75, 1.72 and 1.41 respectively

APPLICATION OF ARTIFICIAL FEED WITH DIFFERENT PROTEIN CONTENT ON BLACKSADDLED CORAL GROUPER Plectropomus laevis NURSERY

Blacksaddled coral grouper Plectropomus laevis is an export commodity and possess high economic value in Asian markets, but the wild population is already threatened. The purpose of this study was to determine the best food for improving growth and survival rate. The nursering were conducted using 9 fiberglass tanks with 1 m3 of volume for 6 month, with three treatment and 3 replicates. Three different foods were used as treatments, i.e.: Local commersial pellet with crude protein content 50% (A), im-port  commersial pellet with cure protein content 55% (B) and trash fish (sardine) (C). The initial size of blacksaddled coral grouper seed were 2.5 cm total lengths (TL), 0.45 g body weight (BW). The stocking density of fry was reared at 250 fish per m3. A complete random design was used as an experiment design. Data was analysed using ANOVA statistics. Feeding times were twice a day at 08.00 and 15.00 local time; with dose at satiation. The samplings of fry were conducted every 15 day to measure of survival rate (SR), TL and BW. On the end of experiment was calculated economic ana-lized (BC ratio). The result showed that there was significant different (P<0.05) among treatments for SR and growth rate (GR). The better SR and GR was at treatment B with SR 96.5%, and GR 0.75g/day followed by treatment C (SR 90.5%: GR 0.54g/day) and treatment A (SR 81.5%: GR 0.42g/ day. The food conversion ratio was 1.15 in treatment A, 1.02 in B and 4.81 (wet weight) in C. From economic analized showed that the best BC ratio was in pellet 55% protein (B), followed by trash fish (C) and pellet 50% protein (A) with BC ratio of 1.75, 1.72 and 1.41 respectively.

Development of Digestive Enzymes Activity on Black Saddled Coral Grouper (Plectropomus Laevis) Larvae

Protease, amylase, and lipase enzymes were used as biological indicators to measure larvae's food digestion. The aim of this study was to describe digestive enzyme activity development of black saddled coral grouper (Plectropomus laevis) larvae. The just hatching larvae were reared in concrete tank 2x3x1 m3 with stocking density of 10 larvae/L. In the larval rearing media were added with Nanochloropsis oculata at 105 cel/ml started from 1 day old (D-1). The larvae was fed with rotifer (Brachionus rotundiformis) at 10-20 ind/ml started from D-2 and artificial diet from D-10. To analyze the protease, amylase, and lipase enzymes activities, samples were taken 0.5-1 g or about 1000 larvae on D-3, D-4, D-6, D-8 and 500 larvae on D-10, D-12, D-16, and D-20. The result showed that the protease, amylase, and lipase enzymes activity were positively correlated with the growth. Digestive enzymes activity was increased when larvae started on endogenous feeding (D-3), become down on D-6, stable on D-8 to D-10, increased on D-12, and reached the highest level on D-16. Digestive enzymes activity was higher when larvae started feeding with artificial diet compared to the larvae before feeding with artificial diet

PEMATANGAN GONAD DAN PEMIJAHAN INDUK IKAN NAPOLEON (Cheilinus undulatus) DENGAN PERBANDINGAN SUMBER PROTEIN PAKAN YANG BERBEDA

Untuk pengembangan budi daya ikan napoleon, Cheilinus undulatus perlu disiapkan teknologi perbenihannya

EXPERIMENTAL INFECTIONS OF MILKY HEMOLYMPH DISEASE IN SPINY LOBSTER Panulirus homarus

Milky hemolymph disease of spiny lobster (MHD-SL) is categorized as the most destructive disease in farming spiny lobster. Therefore, it is required to investigate the routes of milky disease infection in spiny lobster as a basic knowledge in order to prevent milky disease transmission. The aim of the present study was to perform an experimental infection of milky disease in spiny lobster Panulirus homarus. Experimental infection of milky disease was carried out by several modes of infection which were injection, immersion and per os exposure. Injection of each 0.2 mL undiluted and diluted hemolymph from the diseased lobster resulted in a cumulative mortality of 100% at 15 days post-infection (dpi), and 75% at 16 dpi, respectively. Experimental infection through water immersion caused in a cumulative mortality of 50% at 7 dpi. In contrast, no mortality was observed in per os exposure as well as in control groups. Results of this experimental study provided evidence for horizontal transmission of MHD-SL among P. homarus. Histopathological analysis exhibited that there were masses of Rickettsia-like bacteria (RLB) in the connective tissues of the gill, hepatopancreas, gonad, midgut, and muscle tissues of the affected lobsters. Mass of RLB was not only found in the moribund lobsters but also in the surviving lobsters with milky hemolymph appearance

PENGAMATAN PEMIJAHAN ALAMI, PERKEMBANGAN EMBRIO DAN LARVA IKAN KERAPU BATIK, Epinephelus microdon DALAM BAK TERKONTROL

Kerapu batik, Epinehelus microdon telah berhasil dipijahkan di Loka Penelitian Perikanan Pantai Gondol. Wadah pemeliharaan berupa bak beton volume 20 m3 yang diisi 16 ekor induk (4 jantan dan 12 betina) dengan ukuran bobot 1500-2500 gram, pergantian air 400% hari dan pemberian pakan dengan ikan dan cumi-cumi 3-5% biomassa per har

Editorial of the First Edition Journal of Sylva Indonesiana

This editorial is an opening remark of the first edition Journal of Sylva Indonesiana (JSI) containing the growth and development of the journal managed by Faculty of Forestry Universitas Sumatera Utara (“Fahutan USU”). In the first stage, “Jurnal Ilmiah Pertanian Kultura” published by Faculty of Agriculture USU has been targeted by faculty member of “Fahutan USU” for dissemination of their research results. This journal has been accredited by Directorate General of Higher Education in 2003 consequently its scope become specific, forestry science did not include therein. Hence, at that time, Program Study of Forestry Science under management of Faculty of Agriculture USU initiated the issuing of Peronema Forestry Science Journal in 2005 in order to accommodate scope of forestry science. Unfortunately the service and production of this journal become stagnant because most of the editorial staff pursued higher education in outside Medan city and the funding for publishing and printing vanished. In 2012, with the new spirit, Program of Forestry Science re-issued the new journal called “Foresta” Indonesian Journal of Forestry. It was a pity, the production process of this journal discontinued regarding to no submission of the manuscripts. All of the research results of undergraduate students of Program Study of Forestry Science have been uploaded into Peronema Forestry Science Journal in online version since 2014. In connection with establishment of organization structure of Faculty of Forestry completely, the publishing of JSI has been started in 2018 even though the editorial works of this journal has been begin since 2017, comprise call of paper, blind-review process, correspondence with the authors, layout and editing, including upload in the journal website. Supply of the manuscripts is provided not only from undergraduate research results of Faculty of Forestry’s students but also from the outside. With the commitment of the funding from the Faculty of Forestry USU, hopefully JSI can reach the target as the national accredited journal and it can achieve the status to be a reputation journal in the field of forestry in the future

MONITORING MUSIM, FEKUNDITAS DAN KUALITAS TELUR IKAN KAKAP PUTIH, Lafes calcarifer DARI HASIL PEMIJAHAN ALAMI DALAM KELOMPOK

Pengamatan musim pemijahan alami pada ikan kakap putih bertujuan untuk mengetahui efektivitas pemijahan dilihat dari musim, fekunditas, derajat pembuahan, dan penetasan telur. Induk betina yang digunakan untuk pemijahan memiliki bobot tubuh (BW) 1 ,8-4,2k9 (TL 48-68 cm) dan jantan 1,5-2,0 kg (TL 47-56 cm) dengan rasio 8 :

Correlation Between Community Knowledge Level of River Ecosystem Services and Littering Behavior in Belawan Hilir Sub-watershed

Belawan watershed is one of the watersheds that have a primary role in North Sumatra Province. The flow of the Belawan watershed crosses 2 (two) regencies/cities, i.e., Deli Serdang Regency and Medan City. In more detail, Medan City is located in the Belawan Hilir Sub-watershed. Several main rivers in Medan have been polluted and shallowed, as a result of people's habit of littering the river. People who live around the Belawan watershed have a significant role in the sustainability of the river and its ecosystem services. This study aims to analyze the level of community knowledge of river ecosystem services in the Belawan Hilir sub-watershed and to measure the correlation between the community knowledge level and the behavior of river littering. The respondents were sampled using Simple Random Sampling, while the number of samples was calculated using the Slovin formula. Data was collected through structured interviews by compiling a list of questions (questionnaires). The correlation between community knowledge levels and behavior of river littering was determined using spearman correlation analysis. The community knowledge level was 63% (good category). There was a moderate-positive correlation between the community knowledge level and the behavior of river littering (0.512 correlation coefficient). Community awareness can be increased through online-based socialization using social media or by providing more waste management training programs

THE GROWTH PATTERN OF BLACKSADDLED CORALGROUPER LARVAE (Plectropoma laevis LACEPÈDE, 1801) AND THEIR CONSUMPTION RATE TO ZOOPLANKTON ROTIFER (Brachionus rotundiformis)

Blacksaddled coralgrouper Plectropoma laevis has been started to conserve to prevent from over exploitation. The study purposes were to determine the growth pattern during larvae to juvenile stage of Blacksaddled coralgrouper and their consumption rate to zooplankton rotifers Brachionus rotundiformis. Domesticated broodstocks have been rearing in 100,000 l concrete tanks. The eggs from spawning broodstocks were hatched and the larvae have been kept to juvenile. Larvae rearing was done in 6,000 l concrete tanks. During the rearing period, larvae were fed with zooplankton rotifer, artemia and artificial food. Parameters measured were eggs and oil globule diameter, larval total length, length of larval dorsal fin and ventral fin, the number of zooplankton that consumed by larvae and water temperature. Microscopic method was used to measure the parameters. The result showed that eggs and oil globule diameter ranged in 800-850 μm and 168-200 μm, respectively. Total length of newly hatched larvae was 2.53±0.13 mm. The growth pattern of total length from larva to juvenile stage was exponential, while the growth pattern of dorsal fin and ventral fin length was linear. Larvae grew very fast after 35 days old. The pattern of larval consumption rate to zooplankton rotifers was linear. Time period from larvae to juvenile stage was 45-55 days on water temperature 27-29oC.Keywords: growth, consumption rate, rotifers, larvae, Blacksaddled coralgroupe