Integrative Transcriptomics and Metabolomics Analysis of Body Color Formation in the Leopard Coral Grouper (Plectropomus leopardus)

Body color is an important economic and ecological trait in aquatic animals, which influence their economic values and determine the animal ability to survive in the marine environment. Red-colored Plectropomus leopardus is in high demand owing to its bright color and potential value for artificial breeding. High-throughput transcriptome sequencing and liquid chromatography tandem-mass spectrometry (LC-MS/MS) approaches were used to identify transcript and metabolic differences between black-colored and red-colored P. leopardus. Compared with the black-colored group, 218 and 181 differentially expressed genes were up- and down- regulated, respectively, in the red-colored group. 425 and 56 significantly different metabolites were identified in LC-MS positive and LC-MS negative ion models, respectively, between two colored groups. Based on the integrative analysis, the red-colored group exhibited greater carotenoid uptake, transport, and accumulation activity potential than those in the black-colored group and may consume more arachidonic acid for body color formation. The black-colored group showed greater melanin synthesis activity compared with the red-colored group. These results substantially improve the understanding of molecular and metabolic mechanisms underlying body color formation in P. leopardus and the potential of body color for the environment adaptation.

Penentuan Komoditas Unggulan Perikanan Tangkap di Perairan Provinsi Kepulauan Bangka Belitung

consisting of 954 islands with 218.236 tonnes capture fisheries potential. As a leading economic sector in the region, capture fisheries should be maintained sustainably. One of actions that can be done is focusing fisheries development on prime commodities. Purpose of this study were to identify prime commodities and potential commodities in Bangka Belitung waters. Location Quotient (LQ) Analysis, Shift Share (SS), and Specialization Index (SI) were used for data analysis. The result showed that there were three prime commodities i.e., red snapper (Lutjanus campecanus), mackerel (Scomberomorus commerson), and blue swimming crab (Portunus pelagicus). Other potential fisheries commodities in Bangka Belitung Province were grouper (Plectropomus leopardus), yellowtail (Caesio erythrogaster), sea catfish (Arius thalassinus), fork-tailed threadfin bream (Nemipterus furcocus), stingray (Dasyatis sp), and crab (Scylla serrata). Keywords: Bangka Belitung Province, capture fisheries, prime commodities

PENGGUNAAN ALGA GEL (NATACLHORELLA) DALAM LARVA REARING UNTUK MENINGKATKAN SURVIVAL RATE BENIH KERAPU SUNU (Plectropomus leopardus)

Kondisi Pulau Ambon yang sering hujan memberikan dampak yang kurang menguntungkan bagi kegiatan pembenihan di BBL-Ambon. Hal ini disebabkan perkembangan fitoplankton yang merupakan makanan alami bagi pertumbuhan larva dan benih tidak optimal dan mengalami kematian. Keterbatasan ketersediaan fitoplankton dapat menyebabkan kegagalan dalam kegiatan pembenihan secara keseluruhan. Ini karena fungsi dari fitoplankton sangat vital bagi kelangsungan hidup larva. Fitoplankton selain berfungsi sebagai makanan zooplankton juga menstabilkan kualitas air media pemeliharaan. Natachlorella merupakan salah produk dari fitoplankton yang dipadatkan dari jenis Chlorella dalam bentuk gel. Penggunaannya kini semakin berkembang di instalasi pembenihan pada saat kondisi musim hujan dan intensitas matahari rendah.Penggunaan natachlorela dalam pembenihan kerapu sunu belum pernah dilakukan, ini karena perkembangan pembenihan kerapu sunu yang belum berkembang optimal. Untuk itu dalam kegiatan pembenihan kerapu sunu dalam kondisi hujan BBL-Ambon menggunakan natachlorela yang dilarutkan dalam media pemeliharaan.Kegiatan ini dilakukan selama 3 siklus pemijahan dari bulan Oktober – Desember 2012. Pemberian plankton (natadechlorella sp) dilakukan pada umur larva D2 sebanyak 1 kali sehari dan diberikan pada waktu pagi hari. Ketika larva berumur D3 - D25 plankton diberikan 2 kali sehari (pagi dan sore), dengan dosisi 20 ml/10 ton air laut.Hasil yang diperoleh dari 3 bulan siklus pemijahan adalah 1020 ekor benih kerapu sunu (P. leopardus) ukuran 3 cm

OPTIMUM DENSITY OF Nannochloropsis sp. FOR MASS SCALE CORAL TROUT, Plectropomus leopardus (Lacepède, 1802)

Coral trout, Plectropomus leopardus (Lacepède, 1802)is a visual feeder. Turbidity caused by phytoplankton or clay particle in the water will affect the visual foraging of coral trout larvae. Addition of Nannochloropsis sp. has been included in standard operational procedure for marine fish larval rearing as green water. However, the density of Nannochlorposis sp. in coral trout larval rearing system has not been evaluated. This study aimed to evaluate the optimal of Nannochloropsis sp. required for rearing of coral trout larvae. Nannochloropsis sp. was given to two days old larvae (D-2), with the densities of 2 x 105, 4 x 105, and 6 x 105cell/mL. After 50 days rearing period (D-50), evaluation on the average size and total harvest were recorded. The results showed that the density of 2 x 105 cell/mL Nannochloropsis sp. was the best in survival rate (2.35 ± 1.05%) than other densities, but they were not significantly different (P>0.05) than those of 4 x 105 cell/mL (1.67 ± 0.70%) and 6 x 105 cell/mL (1.26 ± 1.05%). The lower densities, 2 x 105 and 4 x 105cell/mL, were dominated by more than 50% of > 2.7 cm sized juvenile. Histological analysis of fish eyes supported that the two lower densities produced dominant cone shape as the receptor cells in the retina observed. From an economical aspect, addition of 2 x 105 cells/mL resulted on the higher profit, hence optimum density of Nannochloropsis sp. added in coral trout larval rearing on a mass scale was 2 x 105 cells/mL.