Indonesia

Performance of Eel (Anguilla bicolor) maintened in containers of different colors. Growth is the main driver in increasing the profitability of aquaculture. In addition to maintenance management the color of the container is also a factor supporting the growth of eels. This study aims to determine the effect of the color of different rearing containers on the growth and appetite response of eel. The test fish used were elver stage eels with an average weight (129 ±131g). The method used is an experiment with two treatments they are grey and green. The test fish were placed in a container measuring 19x4 m2 and a water level of 1m with a stocking density of 1100 individuals each, 30 days of rearing. The variables observed were growth performance including SR (Survival Rate), ADG (Average Daily Growth), FCR (Food Conversion Ratio), SGR (Specific Growth Rate). The results obtained indicated that there was a significant difference in the average growth of fish reared in grey and green containers. Grey container treatment was proven to get higher yields with average final weight values (192.4 ± 4.5 g), FCR (1.01 ± 0.02), ADG (2.01g/day ± 0.06), SGR (1 .25%BW/day±0.02). Based on the results of the study it can be concluded that there is a significant difference in the growth of eels reared in ash and green containers. The color of the ash container proved to be better in supporting growth performance.Keywords: Elver; Green; Grey; Nocturnal

The Japanese abalone “tokobushi” (Haliotis diversicolor Reeve) supports a valuable fishery off Tanegashima Island, southern Japan. However, catches have been declining, probably caused by over harvesting and other factors. Understanding the effects of macroalgal type and water temperature on the consumption rates of tokobushi has applications for the management of its population such as to identify sites with appropriate quality and quantity of macroalgae and the favorable water temperature during stock enhancement. Under controlled conditions, the effects of macroalgal type and water temperature on the macroalgal consumption rates of tokobushi were evaluated. On a short-term basis (24-h feeding), consumption rates were higher on leathery brown algae (Sargassum fusiforme, Sargassum patens, Sargassum duplicatum, Sargassum alternato-pinnatum, Undaria pinnatifida and Laminaria japonica), corticated red algae (Acanthophora spicifera, Gracilaria gigas, Carpopeltis affinis and Ceramium sp.) and foliose green algae (Ulva pertusa and Enteromorpha intestinales) than on siphonous green algae (Codium spp.) and filamentous green algae (Chaetomorpha crassa and Cladophoropsis zollingeri). Averaged across 20 species of macroalgae, the mean consumption rate was 4.96 ± 0.27%wet-TW.d−1 (wet alga and wet abalone; TW = total weight) or 1.37 ± 0.19%dryTW.d−1 (dry alga and dry abalone). On a long-term basis (20 days feeding), tokobushi had higher consumption rates on the green alga Ulva pertusa and the brown alga Sargassum fusiforme than on the red alga Meristotheca papulosa. When presented with a choice of species (3 days feeding), tokobushi ate more of the brown alga Sargassum fusiforme and the red alga Gracilaria gigas than the green alga Codium cylindricum. Consumption rates generally increased with temperature. Generally, tokobushi prefer macroalgae with high percent dry weight composition, most of which are brown and red algae, and eat more at water temperatures around spring/fall (17°C, 21°C) and summer (27°C) in Kagoshima, Japan.

This research was conducted at Hatchery Fishery Laboratory in University of Muhammadiyah Malang on February 15 - March 17, 2018. The purpose of this research was to identify the meat bone meal (MBM) and poltry by-product (PBM) test on granule and the best treatment to the growth and survival rate of Eel (Anguilla bicolor) stadia elver. The method used was experiemental by Completely Randomized Design (RAL) with 3 different treatments on granule composition, P1 (Commercial Granule), P2 (70% Commercial Granule and 30% MBM), P3 (70% Commercial Granule and 30% PBM), and each treatment done repeatedly three times. Furthermore, the data were analyzed by ANAVA and continued with BNT test. The results of this study indicated that the meat bone meal (MBM) and poltry by-product (PBM) test on granule had a significant effect on the absolute growth rate, a very significant effect on DGR, and not significantly different on Eel. The absolute best growth rate was on P2 2.24 ± 0.71. The best DGR was on P1 (5.55 ± 0.33). Based on the research results, it was concluded that feeding the granule based on meat bone meal increased the growth and survival rate, and also could be the substitution granule for Eel ( Anguilla bicolor). Keywords: Anguilla bicolor, MBM, PBM, Growth

Aquatic plants are always exposed to various types of stresses and the marine algae have been considered as useful bioindicators for detecting different kinds of environmental alterations. Present investigation was carried out to test the comparative response of red algae (Gracilaria salicornia and Digenea simplex) and green algae (Enteromorpha compressa and Sargassum muticum) to the contaminants present in their surrounding growth medium. The results of the study show that the studied macroalgae responded differently in terms of physiological and biochemical parameters. Green algae exhibited higher concentration of Chl a, b, total chlorophyll content and Chl a:b ratio and carbohydrates content. Whereas, red algae showed higher content of carotenoids, phycocyanin and phycoerythrin and protein content. Moreover, red algae G. salicornia and D. simplex showed lower level of hydrogen peroxide content and TBARS and higher values of proline and glycine betaine content and activities of antioxidant enzymes viz. superoxide dismutase, peroxidase, and catalase than the green algae. Taking all these together, it can be concluded that red algae possess strong defense system than the green algae. Among the studied species, red algae G. salicornia was found best in having a stronger defense system.

Agar, a natural biopolymer extracted from red algae, holds immense potential for revolutionizing healthcare, including biomedical engineering. This study explores the feasibility of extracting agar from red algae (Gracilaria tenuistipitata) abundantly available in the coastal area of Cox’z Bazar, Bangladesh. Five extraction methods were investigated, including control and treatments with water and NaOH solutions at 2%, 4%, and 6% concentrations. Each method was applied to three extraction cycles, producing 15 samples for comprehensive analyses. The extracted agar samples were characterized through Fourier-transform infrared spectroscopy (FTIR), gel strength testing, melting and gelling temperature assessments, pH value measurement, and sulfate content analysis to determine their suitability for potential biomedical applications. Statistical tools such as ANOVA and Tukey's HSD test were employed to evaluate the influence of the pretreatment process on the yield and characteristics of agar. The results revealed significant variations across methods, emphasizing the critical role of extraction conditions in determining agar yield and characteristics. Among different alkali treatment methods, the sample processed with 2% NaOH and two hours treatment provided the highest agar yield of 11.67 %. Thus, two hours treatment with 2% NaOH was determined to be the optimal condition for agar extraction. This preliminary study suggests that the red algae is a promising source of agar for wider applications, including biomedical engineering. The agar extracted from abundant local sources in Bangladesh could unlock its potential for advancing healthcare solutions and sustainable national economic growth.

This research was designed to evaluate the nutrient content of brown (Laminaria Sp. and Padina australis) and red algae (Eucheuma cottonii and Gracilaria Sp.) from Kelapa beach, Tuban, East Java. The algae were cleaned from dirt and other materials before drying under the sun. All of the algae were ground and analyzed using proximate analysis (dry matter (DM), ash, organic matter (OM), ether extract (EE), crude protein (CP), crude fiber (CF), and nitrogen-free extract (NFE)) and gross energy with a bomb calorimeter. Data were analyzed descriptively by calculating the average of data obtained. The result showed that brown algae of Padina australis had the highest DM (30.59%) and CP (12.57%). The red algae of Eucheuma cottonii had the highest OM (76.58%), EE (2.85%), CF (8.80%), NFE (56.38%), and gross energy (2,911 Cal/g) but had the lowest DM (13.67%) and CP (8.55%). In opposite with Gracilaria sp. had the highest ash (65.63%) and the lowest OM (34.37%), EE (0.21%), CF (2.49%), NFE (19.95%) and gross energy (1,083 Cal/g). Based on this study, brown algae (Laminaria sp and Padina australis) and red algae (Eucheuma cottonii and Gracilaria sp.) have the potential as ruminant feed, especially as mineral and soluble carbohydrate sources.

Eel is a species with high economic value, but its slow growth and low survival rate are problems that need to be addressed through the development of effective cultivation technology. This study aimed to investigate the effects of vitamin C dosage on the growth and survival of eels (Anguilla bicolor). This study was conducted at the UPR. Mina Mandiri, Beutong District, Nagan Raya Regency, during the period August to October 2023. The method used was a completely randomized design with four treatment levels and three replications, namely 0, 200, 300, and 400 mg/kg feed. ANOVA results showed that the dose of vitamin C had a significant effect on the growth and survival of eels (P < 0.05). Further tests using Duncan's method showed significant differences between treatments in growth parameters, but there was no significant difference in survival. The 200 mg/kg feed dose showed the highest and optimal results in terms of increasing the growth and survival of eel fish.Keywords: Culture technology; eel; growth; vitamin C

Two types of ubiquitin genes were isolated from the marine red alga Gracilaria lemaneiformis: a ubiquitin-52 amino acid fusion protein gene, and a 6-unit polyubiquitin gene. Alignment of polyubiquitins among three red algae (Gracilaria lemaneiformis, Gracilaria verrucosa, Aglaothamnion neglectum) and other species revealed that there were six ubiquitin repeats in all three red algae polyubiquitins, and that glutamine was the final amino acid residue in the terminal repeat of the polyprotein in the two Gracilaria sequences. Southern blot analysis revealed that both genes were encoded by low-copy number genes. Semi-quantitative RT-PCR was performed to investigate the expression of these two genes in two phases of G. lemaneiformis. The result revealed that the monoubiquitin was phase-relative, and upregulated in tetrasporophytes compared with female gametophytes. The polyubiquitin gene was expressed at similar levels in both phases.

Activated carbon obtained from red algae Gracilaria changii was used as an adsorbent to remove Pb (II) and Cu (II) from an aqueous solution. The raw red algae were first impregnated with phosphoric acid, followed by thermal activation. The Box–Behnken design was used to optimize the activation process. The optimum activation parameters were 84%, 650 °C, and 175 min for acid concentration, activation temperature, and activation time, respectively. The obtained activated carbon had a high surface area of 867 m2/g. The removal of Pb (II) and Cu (II) was evaluated using a batch adsorption study. The effect of solution pH on the removal of metal ions was investigated within the range of 2–7. The effect of three important adsorption parameters (initial metal ion concentration, adsorbent dosage, and contact time) was analyzed using central composite design. The optimum removal of Pb (II) and Cu (II) was 76% and 36%, respectively. The adsorption kinetics obeyed the pseudo-second-order model, while the adsorption isotherm obeyed the Langmuir model.

Insects are a potential substitute for conventional meat and can be part of a sustainable human diet due to their valuable nutrients and relatively low environmental production impact. One species that is already produced for human consumption and livestock feed is the mealworm, i.e., larvae of Tenebrio molitor. Knowledge of the effects of temperature, and particularly photoperiod, on mealworm development is scarce, but crucial for the improvement of rearing. Therefore, the effects of three temperatures (20 °C, 25 °C, and 30 °C), in combination with three photoperiods (long-day-16 h:8 h light:dark; short-day-8 h:16 h light:dark, and constant darkness) on mealworm survival, developmental time, and growth rate were tested. We describe a significant effect of temperature on survival rate, developmental time, and growth rate. Furthermore, significant effects of photoperiod on developmental time and growth rate were found. At 25 and 30 °C and constant darkness, the highest survival and growth rate, along with the shortest developmental time, were observed. Our data can be used to improve the mass rearing of mealworms for an efficient production of food and feed.

This work aims to test growth methodology and to evaluate cultivation potential of the red algae Hypnea musciformis (carragenophyte), Gracilaria cervicornis (cf.) and Gracilaria caudata, (agarophytes). In vitro growth was tested for the three algae, and in situ growth was tested for Gracilaria cervicornis (cf.). Preliminary results indicate high growth rates to in situ and in vitro tests, when compared to literature results. Gracilaria cervicornis (cf.) in vitro growth rates ranged from 1,8 to 5,7 % day-1, and in situ growth rates ranged from 2,3 to 8,7 % day-1. Gracilaria caudata presented lower growth rates, which ranged from 0,8 and 4,9 % day-1. Hypnea musciformis presented highest growth rates, which ranged from 5,6 and 15,2 % day-1. This results are preliminary. For a good evaluation of productive and cultivation potencial of this algae, complementary tests are needed. However, observed growth rates suggest this algae deserves more research aiming to implement its cultivation on Enseada de Armacao do Itapocoroy (Penha, SC).

Wound healing in the mouth has its challenges due to masticatory movements and the presence of bacteria that can inhibit its process. The aim of this study was to analyze the contents of red algae (Gracilaria verrucosa) from Indonesia, and its potential as a wound-healing agent for oral wounds using animal model. Red algae content was determined by phytochemical tests and gas chromatography-mass spectroscopy (GC-MS). The wound was made by making an incision on the gingival mucosa of Rattus norvegicus and the parameters assessed were bleeding time, number of fibroblast cells, and time of wound closure. Three doses of G. verrucosa gel were used (2.5%, 5%, and 10%) and the gels were applied twice a day, at 6:00 and 18:00. Application was carried out topically by applying 0.1 ml of gel to the incision wound using a 1 mL syringe. Our phytochemical test indicated that the G. verrucosa contained alkaloids, steroids, flavonoids, and phenols. The dominant contains of the G. verrucosa were glycerol (36.81%), hexadecenoic acid (20.74%), and cholesterol (7.4%). The hemostasis test showed that the 2.5% G. verrucosa extract gel had the shortest bleeding time, 33.98±2.66 seconds. On the seventh day of the initial proliferation phase, the number of fibroblasts was not significantly different among groups. On day 14, the number of fibroblasts was only significantly different between 10% G. verrucosa and untreated group (p=0.007). On day 28, however, both 5% and 10% G. verrucosa were significantly higher compared to untreated group, both had p=0.010. Daily clinical examination showed that animals that were given 2.5% and 5% of G. verrucosa extract gel experienced wound closure on day 10. Animals treated with 10% of extract gel, all wounds healed on day 9. This study suggested that G. verrucosa extract could accelerate wound closure and wound healing.

The activities of selected biomarkers including 7-ethoxycoumarin-O-deethylase (ECOD) and glutathione S-transferase (GST) were measured in the red algae (Gracilaria corticata) obtained from the Oman Sea. Chemical analyses were used to assess the polycyclic aromatic hydrocarbons (PAHs) in the red algae. Total PAH concentrations in the red algae ranged from 3.61 to 8.14 ng g-1 dry weight. Mean GST and ECOD activity also varied from 8.87 to 15.32 nmol/mg protein/min and from 0.31 to 1.02 pmol/min/mg protein, respectively. Significant correlations were found between the total PAH levels and the selected biomarkers (p < 0.01). The results showed that ECOD and GST enzymes reacted to PAHs in phase I and II detoxification mechanisms of red algae (G. corticata), which extend the use of these biomarkers for investigation of the biological effects of PAH pollution as well as determination of pollution bioavailability. Environ Toxicol Chem 2019;38:1947-1953. © 2019 SETAC.

The growth of over a 1000 eels from three different watersheds was investigated. Because of the difficulties of sexing eels we were only able to compare the size of females with that of eels with lobulate organs (some of the latter are potential females). Generally female eels grow faster than the others. There was little difference in the growth of eels with lobulate organs even though there was a great difference in the eel population density in the three localities. But, in any one locality there was a large range of growth. It is suggested that the competition for food is most acute amongst the smaller size groups. As they grow, eels tend to become cannibalistic and find small eels and elvers an easy source of food.The growth of some continental eels has been related to temperature but this is not confirmed by experimental work. Nevertheless eels eat little or nothing at low temperature as is shown by the large percentage of eels with empty stomachs in our samples.

Ikan Sidat or eel fish ( A nguilla bicolor) is a popular fish commodity in domestic trade as well as for export commodity. The use of marine yeast as fodder suffers from some weaknesses since it contains nucleic acids and rigid thick cell walls that obstruct the absorbance of nutrition. Optimizing the use of marine yeast as fodder ingredients can be done by fragmenting and reducing the yeast. This research attempts at optimizing the use of marine yeast regarding its rate of growth, fodder efficiency and the survival rate of eel fish. This research employs the complete random design using 4 different treatments and 3 repetition. In the four treatments, the fodder contained protein (45%) and iso energy (3.600 kkal.kg -1 fodder), which were applied to the treatment A 0% (control), B 5% (complete), C 5% (fragmented) and D 5% (reduced). The parameters used in this study were survival rate, specific growth rate, ratio of fodder conversion, ratio of protein efficiency, energy retention, protein retention and rate of metabolism. The data of this study showed the best result in the treatment D, 5% (reduced), showing survival rate value of 95.56%, specific growth at 1.12, food conversion ratio of 2.27, protein efficiency ratio of 0.98, protein retention at 18.26%, energy retention of 16.57, and protein metabolism rate at 81.96%. Keywords: eel fish, growth, marine yeast.