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In this study, the effects of oral administration of probiotic Bacillus sp. D2.2 and prebiotic from sweet potato extract on growth performance and resistance against Vibrio harveyi in Pacific white shrimp (Litopenaeus vannamei) were investigated. During 32-day feeding experiment, 360 individuals of Pacific white shrimp (PL15) with initial weight of 0.02 ± 0.002 g were fed with basal diet as control (A); supplemented with 6% probiotic and 0% prebiotic (B); 6% probiotic and 2% prebiotic (C); 6% probiotic and 4% prebiotic (D). At the end of feeding trial, weight gain (WG), average daily growth (ADG), feed conversion ratio (FCR), and survival rate (SR) were assessed. WG, ADG and FCR of the shrimp were significantly better in treatment D than those of the shrimp in other treatments. Control and treatment D as the best feeding trial were selected for challenge test with infectious V. harveyi. Survival rate and mean time to death (MTD) of the shrimp fed the supplemented diet were not significantly different (P>0.05) to the control. Infection levels in shrimp were evaluated using morphological scoring methods. Infection levels of V. harveyi in shrimp fed the diet were lower compared to the control.

Redclaw crayfish (Cherax quadricarinatus) is a freshwater crayfish with high economic value, which entices fish farmers to farm and increases its production. Males of this species have larger harvest size than females, so it is proposed to culture an all-male population for increasing yields. This research aims to find out the effect of sea cucumber steroid extract and 17α-methyltestosterone at different temperatures on sex reversal of juvenile C. quadricarinatus. This research was designed using factorial complete random design method. The treatments were observed in controlled temperatures at 27 °C and 31 °C, with a dose of sea cucumber steroid extracts (SCSE) of 50 mg • kg −1 and 50 mg • kg −1 of 17α-methyltestosterone. The results indicated that both SCSE and 17α-methyltestosterone were most effective at 27 °C on increasing the male percentage of juvenile crayfish, which were up to 75.16 % and 73.79 % respectively. These steroid hormones had a significant effect on decreasing the number of female individuals and also on increasing total length, daily weight gain, and growth of juvenile crayfish. However, they did not make a significant effect on survival rate, the percentage of intersex and feed conversion ratio of juvenile freshwater crayfish.

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Techniques for producing Holothuria scabra or sandfish sea cucumbers from aquaculture have been developed rapidly in the recent years to address the issues of decreasing sandfish population and increasing market demand. During the process of culturing H. scabra, the early stages of sandfish (i.e. larvae and juveniles) are the most critical of the development. Therefore, the Research and Development Division of the Marine Bio Industry -LIPI conducted a study to assess the growth performance of juvenile H. scabra cultured in four different rearing conditions: (i) indoor concrete tank, (ii) indoor fiberglass tank, (iii) outdoor concrete tank with 1 mm hapa mesh, and (iv) outdoor concrete tank with 3 mm hapa mesh. Each of the rearing condition was set with an initial juvenile density of 15 juveniles per tank with a mean initial weight of 14 g, and fed ad libitum with a mixed feed consisting of Enhalus acoroides sea grass, Pennisetum purpureum napier and cow manure. The experiments were conducted for 20 weeks between April 26 -September 23, 2013. After the experimental period, juveniles reared in the outdoor concrete tank with 1 mm mesh show the best performance with respect to their survival rate (48.89 ± 3.85 %), mean final weight (22.07 ± 1.01 g), final biomass (162.05 ± 18.17 g) and specific growth rate (0.15 ± 0.03% per day). Further studies that combine rearing conditions with different bottom substrates as well as investigating the effect of light are needed to optimize the production of H. scabra from aquaculture.

Meningkatnya kebutuhan dan aktivitas teknologi informasi (TI), mengakibatkan meningkatnya kebutuhan sumber daya TI. Cloud Computing merupakan mekanisme yang memungkinkan pengguna "menyewa" sumber daya TI dan memanfaatkan sesuai kebutuhan. Dengan konsep ini akan memberikan keuntungan bagi organisasi, yaitu tidak perlu mengeluarkan biaya operasional, perawatan dan investasi diawal yang besar untuk membeli infrastruktur, sehingga fokus terhadap bisnis utamanya. Selain keuntungan yang ditawarkan, permasalahan lain muncul seperti tingkat layanan, sehingga perlu ada jaminan dan kesepakatan antara penyedia dan pengguna dalam bentuk perjanjian yang disebut Service Level Agreement (SLA). SLA merupakan harapan dan kewajian yang disepakati oleh penyedia layanan dan konsumen, dari mulai penetapan sampai pengakhiran layanan. Penelitian mengusulkan model penilaian kapabilitas proses layanan untuk mengetahui tingkat kapabilitas proses yang mengacu pada ISO/IEC 15504 yang memiliki dimensi proses dan kapabilitas. Setiap proses memiliki tujuan, aktivitas (base practice) dan keluaran (work product) yang merupakan hasil analisis standar pada Cloud Computing. Penelitian mengambil studi kasus di Walden Global Services. Hasil penelitian menunjukan level kapabilitas proses layanan SLA berada pada posisi level 0. Dapat disimpulkan bahwa base practice sebagian kecil dilakukan dan work product sebagian kecil dihasilkan dari aktivitas dan proses yang dijalankan. Untuk meningkatkan level kapabilias proses, diusulkan langkah-langkah peningkatan prosese level kapabilitas sampai level 3.

HighlightToxicity and pathological effects of A. catenella were investigated on shellfish larvaeUnfiltered exudates of A. catenella caused significant mortality of blue mussel larvaeApplication of 0.22 mm filtration on A. fundyense exudates potentially decrease the toxicity effectsPathological effects of A. catenella occurred as early as 3 h after exposureThe prevalence and intensity of necrosis increased with exposure duration to A. catenella exudatesAbstractBlooms of the toxic dinoflagellate Alexandrium catenella have affected shellfish industries globally due to their capacity to produce paralytic shellfish toxins(PST). This study aimed to investigate the toxicity effect of exudate A. catenella on larvae of blue mussel Mytilus galloprovincialis and Pacific oyster Crassostrea gigas and filtration methods to reduce the toxic effect. Blue mussel and Pacific oyster larvae were assessed their survival and histopathological changes after exposure to extracellular exudates of A. catenella ranging from 100 to 1,000 cells ml-1 . The results showed that exposure to exudate A. catenella caused significantly higher larval mortality (39 to 52%) than exposure to an equivalent biovolume of the nontoxic species, Tisochrysis lutea (33%) or unfed controls (17%). Filter-sterilization (0.22 µm) of exudates and activated carbon filtration decreased the mortality of Pacific oyster larvae to a level similar to controls (unfed), with the exception of the highest concentrations (600 and 1,000 cells ml-1 ) and mortality of bluemussel larvae mortality by 32% respectively. Blue mussel larvae exposed to exudate A. catenella showed pathological changes mainly in the stomach (digestive gland and style sac) as early as three hours after onset of exposure. The findings of this study suggest that early detection of blooms in the vicinity of mussel and Pacific oyster hatcheries and taking steps to mitigate their effects, is important to reduce the effects of A. catenella blooms on shellfish larval rearing.