The Journal of Fish Nutrition (JFN) has an objective to publish and provide high-quality scientific contributions to the field of fish nutrition. These contributions are sourced from innovative research that encourages science and technology development in the field of fish nutrition on a national and international scale. This journal serves as a communication medium for researchers, academics, students, and communities.
EFFECTS OF Moina sp. FEEDING FREQUENCY ON THE GROWTH PERFORMANCE AND SURVIVAL OF Hemibagrus nemurus LARVAE
The Asian redtail catfish (Hemibagrus nemurus) is a freshwater species with high economic value and considerable aquaculture potential. However, the development of its culture is still constrained at the hatchery stage, particularly by the low survival rate of larvae during early rearing. This study aimed to evaluate the effect of Moina sp. feeding frequency on the growth performance and survival of H. nemurus larvae. The experiment was conducted for 15 days in June 2025 at the Microalgae and Fish Nutrition Laboratory, Faculty of Agriculture, Universitas Islam Riau, Pekanbaru, Indonesia. A completely randomized design with one factor was applied, consisting of five feeding frequencies and three replicates. The treatments were feeding Moina sp. at frequencies of 1, 2, 3, 4, and 5 times per day. Three-day-old larvae were used, with an initial average body weight of 0.01 ± 0.00 g and an initial average total length of 0.40 ± 0.00 cm. The observed parameters included final weight, final length, absolute weight gain, absolute length gain, specific growth rate, and survival rate. The results showed that feeding frequency had a significant effect on the growth and survival of H. nemurus larvae. The best performance was obtained at a feeding frequency of 5 times per day, resulting in a final weight of 0.09 ± 0.01 g, final length of 1.26 ± 0.01 cm, absolute weight gain of 0.09 ± 0.01 g, absolute length gain of 0.86 ± 0.01 cm, specific growth rate of 18.13 ± 0.38%, and survival rate of 82.00 ± 4.62%. Water quality parameters throughout the experiment remained within acceptable ranges for larval rearing. Therefore, feeding Moina sp. 5 times daily is recommended as the most effective feeding frequency to improve the growth and survival of H. nemurus larvae
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UTILIZATION OF FISHERY WASTE-BASED FEED IN THE CULTURE OF STRIPED CATFISH (Pangasius hypophthalmus)
Siamese catfish (Pangasius hypophthalmus) aquaculture faces the challenge of high feed costs due to reliance on commercial fish meal, while fishery processing byproducts such as bones, scales, heads, gills, and offal remain underutilized and have the potential to pollute the environment if allowed to accumulate. This study aims to describe the utilization of fishery byproducts as raw materials for self-produced feed and to analyze their effect on the growth performance of Siamese catfish fry. The alternative fish meal was processed from waste consisting of heads, bones, skin, and scales through the stages of washing, boiling, roasting, drying, and grinding, then formulated together with rice bran, tapioca flour, and vitamins into pellet-shaped feed. This feed was provided to Siamese catfish fry during a 70-day rearing period, with body weight and length measured every 7 days. The results showed that the fish meal was grayish-brown in color with a fine, uniform texture, while the resulting pellets were brown and had a dense texture. The average fish weight increased from 7.0 grams on day 7 to 13.1 grams on day 70, with an absolute weight gain of 6.1 grams, an absolute total length gain of 2.17 cm, a specific growth rate of 0.99% per day, and a survival rate reaching 100%. These results indicate that fishery waste has great potential to be utilized as a substitute for commercial fish meal in self-sufficient feed formulations that support optimal growth of Siamese catfish fry while reducing environmental pollution caused by waste from the fish processing industry.
ANALYSIS OF THE EFFECT OF ADDING FERMENTED MATURE COCONUT WATER AS AN ADDITIONAL NUTRIENT SOURCE IN COMMERCIAL FEED ON THE GROWTH PERFORMANCE OF CATFISH (Clarias sp.)
This study aimed to analyze the effect of supplementing commercial feed with fermented mature coconut water as an additional nutrient source on the growth performance of African catfish (Clarias sp.). The experiment was conducted using a Completely Randomized Design (CRD) consisting of four treatments: P1 (control), P2 (5%), P3 (10%), and P4 (15%) fermented mature coconut water, equivalent to the addition of 50, 100, and 150 mL per 100 g of commercial feed, respectively. Each treatment was conducted in triplicate using 10 fish per container, with an initial average weight of 17–20 g and an average total length of 8–10 cm, for a culture period of 45 days. The observed parameters included absolute weight gain, absolute length gain, specific growth rate (SGR), feed conversion ratio (FCR), feed utilization efficiency (EPP), and survival rate (SR). Data were analyzed using analysis of variance (ANOVA), followed by Duncan’s Multiple Range Test at a 5% significance level. The results showed that supplementation with fermented mature coconut water significantly affected (P<0.05) absolute weight gain, SGR, FCR, and feed utilization efficiency, but had no significant (P>0,05) effect on absolute length gain or survival rate. The best performance was obtained in treatment P3 (10%), which resulted in an absolute weight gain of 18.66 g, an absolute length gain of 4.11 cm, an SGR of 3.60% day⁻¹, an FCR of 1.12, a feed utilization efficiency of 83.68%, and a survival rate of 93.33%. It can be concluded that supplementation with 10% fermented mature coconut water is the most effective dose for improving the growth performance and feed utilization efficiency of African catfish.
ANALYSIS OF BROILER HATCHERY WASTE AS A PROTEIN SOURCE IN DIETS FOR COMMON CARP (Cyprinus carpio) FINGERLINGS
Common carp (Cyprinus carpio) is a freshwater aquaculture species with high economic value that requires high-quality feed to support optimal juvenile growth. The utilization of chicken hatchery waste meal as an alternative protein source has the potential to reduce the dependence on fish meal in feed formulations. This study aimed to evaluate the effect of fish meal substitution with chicken hatchery waste meal on the growth performance of common carp juveniles. The experiment was conducted for 50 days from March to May 2024 at the Mataram City Fisheries Service, while proximate analysis of the experimental diets was performed at the Laboratory of Animal Nutrition and Feed Science, Faculty of Animal Science, University of Mataram. A Completely Randomized Design (CRD) consisting of five dietary treatments and three replications was applied. The treatments included fish meal substitution with chicken hatchery waste meal at levels of 0%, 25%, 50%, 75%, and 100%. Juvenile common carp (5–7 cm in length) were stocked at a density of 15 fish per container and fed daily at 3% of total biomass. The observed parameters included specific growth rate (SGR), feed conversion ratio (FCR), feed efficiency (FE), survival rate (SR), and water quality. The results showed that replacing fish meal with chicken hatchery waste meal significantly affected (P < 0.05) the specific growth rate (SGR) and feed efficiency (FE). These findings indicate that chicken hatchery waste meal has considerable potential as an alternative protein source in formulated diets for common carp juveniles.
COMPARISON OF IMMERSION AND ORAL ADMINISTRATION OF 17Α-METHYLTESTOSTERONE HORMONE ON MALE SEX RATIO OF NILE TILAPIA (Oreochromis niloticus)
Nile tilapia (Oreochromis niloticus) is one of the most important freshwater aquaculture commodities. The production of all-male populations is considered beneficial due to the faster growth rate of male fish. This study aimed to compare the effectiveness of immersion and oral administration of 17α-methyltestosterone (MT) hormone on male sex ratio in Nile tilapia. A Completely Randomized Design (CRD) consisting of five treatments and three replications was used: P0 (control), P1 (immersion MT 2 mg/L), P2 (oral MT 50 mg/kg feed), P3 (oral MT 60 mg/kg feed), and P4 (oral MT 70 mg/kg feed). Seven-day-old larvae were reared for 50 days. Parameters observed included male sex ratio, survival rate, weight gain, length gain, specific growth rate, and water quality. The results showed that MT treatment significantly increased the percentage of male fish compared to the control. The highest male percentage was observed in P4 (87.8%), followed by P1 (86.7%), P3 (76.7%), and P2 (72.2%), while the control produced only 52.2% males. Hormonal treatments had no significant effect on survival rate, weight gain, length gain, or specific growth rate (P>0.05). It can be concluded that both immersion and oral administration methods were effective in increasing male sex ratio in Nile tilapia with relatively similar effectiveness.
OPTIMIZATION OF Spirulina sp. POWDER DOSAGE IN FEED TO ENHANCE SURVIVAL AND IMMUNE RESPONSE OF JUVENILE GIANT GOURAMI (Osphronemus gouramy)
The purpose of this study was to determine the optimal dose of Spirulina sp. flour in feed that can increase the growth, survival, and immune response of juvenile gourami (Osphronemus gouramy). This study used a Completely Randomized Design (CRD) with 4 treatments and 3 replications, namely, P1 (Control), P2 (Spirulina sp. 3 g/kg feed), P3 (Spirulina sp. 5 g/kg feed), P4 (Spirulina sp. 7 g/kg feed). The results of the study, the addition of Spirulina sp. flour. in feed affects (P<0.05) the growth, survival, and immune response of juvenile gourami (Osphronemus gouramy) with optimal doses of 5 and 7 g/kg feed. This treatment increased growth by 56%, absolute length by 24%, red blood cells by 115%, white blood cells by 121%, hemoglobin by 28%, and survival rate by 80%.
CULTURE OF NATURAL FEED Phronima sp. AT DIFFERENT SALINITY LEVELS
This study aimed to analyze the effect of different salinity levels in the rearing medium on population growth, reproduction, life cycle, and nutritional content of Phronima sp. The research was conducted at the Science and Technology Area Laboratory (KST) Kurnaen Sumadiharga, Marine Aquaculture Research Center BRIN, North Lombok, for 25 days. A Completely Randomized Design (CRD) was applied with four salinity treatments (35, 30, 25, and 20 ppt) and four replicates each. Parameters observed included juvenile count, developmental duration from juvenile to adult, egg count per female, survival rate, and proximate nutritional composition. ANOVA results indicated that salinity differences had no significant effect (P > 0.05) on any biological parameter. The number of juveniles produced ranged from 14.75–16.25 individuals per female, while the number of F1-generation eggs per female ranged from 10.20–10.94 eggs. The life cycle of Phronima sp. lasted approximately 18 days, comprising the egg-bearing female stage (days 0–3), juvenile stage (days 3–15), and adult stage (days 15–18). Survival rate ranged from 70.01–74.97%. The highest protein content was found at 35 ppt (42.01%), while the highest lipid content was recorded at 25 ppt (6.62%). Overall, the salinity range of 20–35 ppt remains within the physiological tolerance of Phronima sp., supporting its successful culture as an alternative natural feed to replace Artemia.
EFFECT OF DIFFERENT DOSES OF A CHICKEN AND QUAIL MANURE MIXTURE ON THE POPULATION GROWTH OF Daphnia sp.
This study aimed to analyze the effect of different fertilizer doses using a combination of 25% chicken manure and 75% quail manure on the population growth of Daphnia sp., as well as to determine the optimal dose of the combined fertilizer for Daphnia sp. population growth. The study was conducted for 16 days using a Completely Randomized Design (CRD) consisting of five treatments with three replications, namely P1 (0 g/L), P2 (2 g/L), P3 (4 g/L), P4 (6 g/L), and P5 (8 g/L). The observed parameters included life cycle, population growth, population density, body length growth, and water quality. The results showed that the application of different doses of combined chicken manure and quail manure significantly affected the population density of Daphnia sp. (p < 0.05), but did not significantly affect the body length growth of Daphnia sp. (p > 0.05). The highest population density was obtained in the P5 treatment (8 g/L) with a value of 1,337 ind/L. The population growth of Daphnia sp. showed adaptation, exponential, stationary, and death phases, while its life cycle consisted of egg, incubation, neonate, juvenile, and adult phases. All water quality parameters were within the optimal ranged. Based on the results of the study, a dose of 8 g/L was the best dose for increasing the population density of Daphnia sp. in a culture medium with a combination of 25% chicken manure and 75% quail manure.
ACUTE LETHAL TOXICITY TEST OF HYPOCHLORITE AGAINST POPULATION CELL DENSITY OF Nannochloropsis sp.
This study aimed to determine the acute lethal concentration of hypochlorite causing 50% mortality of Nannochloropsis sp. cell population within a 2-hour exposure period (LC50-2 hours). The study employed a Completely Randomized Design (CRD) with five concentration levels (0, 7.5, 15, 22.5, and 30 ppm) and four replications. Mortality percentage data were analyzed using probit analysis. The results showed that increasing hypochlorite concentration was linearly associated with increasing cell mortality, yielding the probit regression equation y = 1.5657x + 2.2921 (R² = 0.9101). The resulting LC50-2 hours value was 53.64 ppm. This threshold value is expected to serve as a reference for determining safe application concentrations of calcium hypochlorite in mass culture of Nannochloropsis sp., as well as a basis for further research on its selective effectiveness against zooplankton contaminants.
THE EFFECTIVENESS OF SUPPLEMENTING FEED WITH PROBIO-7 ON THE GROWTH PERFORMANCE AND SURVIVAL RATE OF PANGASIUS (Pangasius sp.)
The pangasius is a freshwater fish that has been cultivated in various locations. The aim of this study was to determine the effect of adding Probio-7 to the feed on the growth and survival of pangasius (Pangasius sp.). The study was conducted at BBIS Noekele, Tuatuka village, Kupang Regency, East Nusa Tenggara Province. This study employed a Completely Randomised Design (CRD) with three treatment levels of Probio-7 dosage, namely 10 ml/kg of feed, 20 ml/kg of feed, and 30 ml/kg of feed. The parameters observed included absolute weight gain, absolute length gain, specific growth rate, survival rate, and water quality parameters comprising temperature and pH. The observational data were analysed using Analysis of Variance (ANOVA) at a 95% confidence level. The results obtained showed that the administration of Probio-7 had a significant effect (P<0.05) on absolute weight gain, absolute length gain, and daily specific growth rate. A Probio-7 dose of 30 ml/kg feed yielded the best results, with absolute weight gain of 15.8 ± 1.4 g, absolute length of 6.9 ± 0.6 cm, and a specific growth rate of 3.56 ± 0.09 g%/day. Survival rates increased significantly at the 30 ml/kg dose, with values exceeding 95%. Water quality during the study remained within the optimal range (temperature 27.8–27.9°C and pH 6.6–6.7). Thus, Probio-7 at a dose of 30 ml/kg of feed effectively enhances the growth and survival rate of pangasius.
EFFECTIVENESS OF PROBIOTIC PROBIO 7 ON GROWTH IN MILKFISH (Chanos chanos)
Chanos chanos or milkfish is an important and highly profitable aquaculture product in Indonesia. However, efforts to increase milkfish growth remain challenging, necessitating strategies to improve feed efficiency. This study was conducted to assess the effect of Probio 7 on the growth of milkfish fed commercial feed at various doses and to determine the most effective dose. A completely randomized design (CRD) was used in this study. This design consisted of four treatments and three replications: A (0 ml), B (10 ml), C (15 ml), and D (20 ml). The results showed that the administration of the probiotic Probio 7 had a statistically significant effect (P < 0.05) on increasing absolute weight growth, specific growth rate (SGR), and feed utilization efficiency (EP), survival rate (SR), and water quality based on all observed parameters. Treatment C (15 ml) was the most effective, with an absolute weight gain of 11.84 g, an SGR of 1.36 g%/day, an EP of 71.92%, and an FCR of 1.39. In all treatments, the survival rate reached 100%, indicating that probiotic administration had no impact on fish survival. Water quality conditions throughout the study remained within the optimum range for fish growth, as indicated by a temperature of 28.3–30.1 °C, salinity of 32–35 ppt, and pH of 7.6–8. The results showed that Probio 7 supplementation at a dose of 15 ml was able to improve nutrient utilization from feed and milkfish growth.
FUNCTIONAL FEED ADDITIVES IN FINFISH AQUACULTURE: GUT HEALTH, IMMUNITY, AND DISEASE RESISTANCE
The intensification of finfish aquaculture has increased the demand for functional nutritional strategies that support growth, gut health, immune competence, and disease resilience while reducing dependence on antibiotics. This narrative review synthesizes peer-reviewed evidence published between 2020 and 2026 on probiotics, prebiotics, synbiotics, phytogenic compounds, essential oils, yeast derivatives, beta-glucans, nucleotides, organic acids, enzymes, seaweed metabolites, and multi-component blends. Current evidence indicates that these additives can improve feed utilization, digestive function, gut microbial balance, mucosal immunity, antioxidant defense, and resistance to pathogen challenge. Their effects, however, depend on additive type, dose, formulation stability, feeding duration, fish species, life stage, rearing conditions, and basal diet composition. Rather than treating functional additives as generic supplements, this review emphasizes their selection according to specific biological targets and production constraints. A precision aquafeed approach that integrates mechanistic understanding with dose-response evaluation, formulation stability, economic feasibility, and farm-scale validation is needed to develop safe, reproducible, and practical functional feeds for sustainable aquaculture.
LEVEL OF DIGESTIBILITY AND ABSORPTION OF CARP (Cyprinus carpio L.) SEED FEED USING A COMBINATION OF GLUTAMINES AND PROBIOTICS
This study aimed to determine the best combination for improving feed digestibility and nutrient absorption in common carp fry. The study employed a factorial Completely Randomized Design (CRD) with two factors: glutamine at different levels (0% /kg feed, 1%/kg feed, 2%/kg feed, and 3%/kg feed ) and probiotics at different levels (0 ml/kg feed, 5 ml/kg feed, 10 ml/kg feed, and 15 ml/kg feed).The results showed that the simultaneous interaction between glutamine and probiotic supplementation had a significant effect (P < 0.05) on the overall feed consumption rate. Based on the findings, the best treatment combination was 2% glutamine supplemented with 10 ml probiotics per kg of feed. This combination produced the following results: Feed Consumption Rate (FCR) of 142.66 ± 2.36 g, Protein Digestibility (PD) of 94.13 ± 1.05%, Feed Utilization Efficiency (FUE) of 93.83 ± 9.89%, Protein Efficiency Ratio (PER) of 2.93 ± 0.31%, and Protein Nutrient Retention (PNR) of 156.69 ± 16.51%.Therefore, the supplementation of 2% glutamine combined with 10 ml/kg feed probiotics is recommended as an effective nutritional strategy to enhance feed utilization efficiency and optimize the growth performance of common carp fry.
PLANKTON DYNAMICS AS NATURAL FOOD INDICATORS DURING NILE TILAPIA (Oreochromis niloticus) LARVAL REARING IN AQUAPONIC, BIOFLOC, AND AQUABIOPONIC SYSTEMS
Plankton communities are important in Nile tilapia larval rearing because they function as natural food, a pathway for nutrient and energy transfer, and an ecological indicator of changes in the rearing medium. This study evaluated plankton abundance, genus composition, and ecological indices during Nile tilapia (Oreochromis niloticus) larval rearing in aquaponic (AP), biofloc (BF), and aquabioponic (AB) systems. A 45-day experiment was conducted using a completely randomized design with three treatments and four replicates. Each experimental unit contained 30 L of water and 30 larvae. Plankton was sampled on days 0, 15, 30, and 45 by filtering 10 L of culture water, concentrating the sample to 50 mL, and observing the concentrated sample using a hemocytometer. Plankton community data were interpreted descriptively, and no statistical significance is claimed for plankton parameters. The three systems developed distinct plankton trajectories. AP showed gradual recovery of plankton abundance and an increase in diversity and evenness by day 45 (H’ = 1.79; E = 0.92). BF produced the highest final abundance, driven by Oscillatoria on day 45 (104.00 ×10³ ind. mL⁻¹; approximately 78% of the community), but showed lower final evenness (E = 0.42) and higher Simpson dominance (C = 0.76). AB showed an early Chlorella peak on day 15 (53.25 ×10³ ind. mL⁻¹) and later shifted toward a more even community by day 45 (H’ = 1.79; E = 0.92). These findings indicate that high plankton abundance does not necessarily represent a balanced natural food community. Based on descriptive plankton community indicators, AP and AB appeared more supportive of balanced plankton communities for tilapia larval rearing, whereas BF required stricter management of organic load, floc volume, pH, and nutrient input to prevent cyanobacterial dominance.
THE EFFECT OF TUNA HEAD MEAL FEED ON THE GROWTH OF NILE TILAPIA (Oreochromis niloticus)
The objective of this study was to determine the effect of using tuna head meal as a substitute for commercial feed on the growth and feed utilization efficiency of Nile tilapia. The method used was an experimental method with a Completely Randomized Design (CRD) consisting of five treatments and three replications, namely P1 (100% commercial feed), P2 (75% commercial feed + 25% tuna head meal), P3 (50% commercial feed + 50% tuna head meal), P4 (45% commercial feed + 55% tuna head meal), and P5 (100% tuna head meal). The observed parameters included feed consumption rate, absolute weight growth, absolute length growth, specific growth rate (SGR), feed utilization efficiency (FUE), feed conversion ratio (FCR), and survival rate (SR). The data were analyzed using ANOVA followed by Duncan’s test at a 95% confidence level. The results showed that feeding with a combination of tuna head meal had a significant effect (P<0.05) on absolute weight growth, SGR, FUE, FCR, and feed consumption, but had no significant effect (P>0.05) on absolute length growth and survival rate. The best treatment was obtained in P4, with an absolute weight growth of 4.93 g, SGR of 0.024%/day, FUE of 54.11%, and FCR of 1.85. Based on the results, it can be concluded that tuna head meal can be used as a substitute ingredient for commercial feed and provides optimal results at a 55% inclusion level.
WATERBORNE POLYSTYRENE MICROPLASTIC EXPOSURE DEPRESSES GROWTH PERFORMANCE OF SIAMESE FIGHTING FISH (Betta splendens)
This study evaluated the effects of waterborne polystyrene microplastic exposure on the growth performance of Siamese fighting fish (Betta splendens) over a 45-day rearing period. A completely randomized design with four treatments and three replicates was applied: 0, 50, 100, and 150 mg/L. The evaluated growth variables comprised absolute length gain, specific length growth rate, absolute weight gain, specific growth rate, feed conversion ratio (FCR), and survival rate (SR). Data were analyzed using one-way ANOVA followed by Tukey’s test at the 5% significance level. Polystyrene microplastic exposure significantly affected absolute length gain, specific length growth rate, absolute weight gain, and specific growth rate (p < 0.05). Fish reared without microplastic exposure consistently showed the highest growth performance, whereas the 150 mg/L treatment produced the lowest values across the principal growth endpoints. By contrast, FCR tended to increase with increasing microplastic concentration, but the effect was not statistically significant (p > 0.05). SR remained 100% in all treatments, indicating that the tested exposure levels produced sublethal rather than lethal effects under the present experimental conditions. Water quality remained within a range generally tolerated by betta fish, suggesting that the observed response was more closely associated with microplastic exposure than with overt deterioration of the rearing medium. Overall, waterborne polystyrene microplastic exposure reduced the growth performance of B. splendens and should be considered a relevant emerging stressor in ornamental fish culture.
THE EFFECT OF INCORPORATING CASSAVA LEAF MEAL WITH FISH MEAL, GROUNDNUT CAKE AND SOYBEAN MEAL BASED DIETS AT THE EXPENSES OF SOYBEAN MEAL ON GROWTH PERFORMANCE AND FEED UTILIZATION OF CATFISH (Clarias gariepinus)
The potential of cassava leaf meal (CLM) as a partial replacement for soybean meal in the diet of African catfish Clarias gariepinus juveniles was carried out in this study. Six isonitrogenous diets containing 35% crude protein were formulated with graded CLM inclusion levels of 0, 5, 10, 15, 20, and 25%. 630 juveniles were randomly distributed into concrete tanks and fed the experimental diets at 3% body weight for 8weeks in a completely randomized design. Each treatment was replicated thrice for the experiment. Proximate composition and cyanide content of the diets were determined, also, growth performance and nutrient utilization parameters were evaluated. No significant differences (p>0.05) were observed among treatments for growth, feed intake, feed conversion ratio, or protein efficiency ratio. However, fish fed the 10% CLM diet consistently showed higher weight gain, specific growth rate, and protein efficiency ratio compared to other treatments. At higher inclusion levels (≥20%), growth performance and feed efficiency tended to decline, likely due to increased dietary fiber and cyanogenic compounds. These findings indicate that cassava leaf meal can replace soybean meal up to 25% without adverse effects on juvenile catfish performance, with an inclusion level of about 10% appearing most favorable. Cassava leaf meal therefore represents a viable, locally available plant protein source for sustainable aquaculture feed formulation.
THE USE OF BIOFLOC MEAL AS A FEED INGREDIENT FOR TILAPIA (Oreochromis niloticus)
This study aimed to determine the optimal percentage of biofloc meal that can be used as a feed ingredient for tilapia (Oreochromis niloticus). The research employed an experimental method using a Completely Randomized Design (CRD) consisting of five treatments with three replications. The treatments included P0 (commercial feed without biofloc, as control), and feeds containing biofloc meal at levels of 20% (P20), 25% (P25), 30% (P30), and 35% (P35). The observed parameters were absolute weight gain and specific growth rate (SGR). The collected data were analyzed using the Kruskal–Wallis test at a 95% significance level. The results showed that the inclusion of biofloc meal up to 35% in the diet produced specific growth rates and absolute weight gains that were not significantly different (p > 0.05) from those obtained with commercial feed. The absolute weight gain ranged from 1.9 to 2.6 g, while the specific growth rate ranged from 1.6 to 2.1% per day. These findings indicate that biofloc meal can be utilized as a feed ingredient in tilapia diets at inclusion levels of up to 35% without negatively affecting growth performance.
OPTIMIZATION OF PHOSPHORUS AND POTASSIUM CONCENTRATIONS TO ENHANCE Chaetoceros amami PRODUCTIVITY AS LIVE FEED FOR PEARL OYSTER (Pinctada maxima)
Chaetoceros amami is a highly nutritious phytoplankton that plays an important role as natural feed for pearl oysters (Pinctada maxima), with its productivity influenced by the availability of phosphorus (P) and potassium (K). This study aimed to analyze the effect of phosphorus and potassium concentrations on the productivity of C. amami using a factorial Completely Randomized Design (CRD) with two factors, namely phosphorus (0, 1, 2, 3 parts per million/ppm) and potassium (0, 3, 6 ppm), with 3 replications, resulting in 36 experimental units. Treatment codes were expressed as combinations of PxKy, where x and y indicate the concentrations of phosphorus and potassium (ppm), respectively; P0K0 served as the control. Nitrogen was kept constant at 7.5 ppm. The parameters observed included peak cell density, relative growth, doubling time, and water quality, measured every 12 hours for 72 hours. The results showed that the treatments and the phosphorus-potassium interaction significantly affected peak cell density and relative growth (p<0.05), but had no significant effect on doubling time (p>0.05). The P1K3 treatment exhibited the best performance (density of 2,592,000 cells/ml; relative growth of 101.3%; doubling time of 48.9 hours), representing an increase of 19.3–47.5% compared to the control, while the P3K0 treatment showed the lowest performance due to nutrient imbalance and phosphorus toxicity. This study recommends the combination of 1 ppm phosphorus and 3 ppm potassium as the optimal formulation for efficient and economical mass production of C. amami, supporting the cultivation of pearl oysters (P. maxima).
EFFECT OF NITROGEN CONCENTRATION ON GROWTH AND PRODUCTIVITY OF Chaetoceros amami AS LIVE FEED FOR PEARL OYSTER LARVAE
Pearl oyster (Pinctada maxima) is a high economic value fisheries commodity whose aquaculture success highly depends on the availability of quality live feed during the larval phase. Chaetoceros amami is a microalgae that plays an important role in supporting the oyster growth. Nitrogen is an important factor affecting microalgae growth as it plays a fundamental role in the synthesis of proteins, nucleic acids, and chlorophyll. This study aimed to analyze the effect of nitrogen concentration on growth and productivity of Chaetoceros amami as live feed for Pinctada maxima larvae. The research was conducted at the Pearl Oyster Hatchery Laboratory of PT. Mutiara Surya Indonesia using a Completely Randomized Design with five nitrogen concentration treatments (0; 2.5; 5; 7.5; 10 ppm) and three replications. Parameters observed included peak density, relative growth rate, and doubling time. The results showed that nitrogen concentration had a highly significant effect (p<0.05) on the growth of Chaetoceros amami. The nitrogen concentration of 7.5 ppm resulted in the highest mean peak density and relative growth rate of 1,985×10³ cells/mL and 133%, respectively, as well as the shortest doubling time of 39 hours, which were significantly different from other treatments. Increasing nitrogen concentration up to 10 ppm actually decreased growth performance by 31.8% due to excessive nitrogen toxicity effects. This study concluded that nitrogen concentration of 7.5 ppm is the optimal concentration for cultivating Chaetoceros amami as natural feed for pearl oyster Pinctada maxima larvae, with a 43% increase in biomass productivity compared to control.
THE EFFECT OF COMBINED FEEDING OF FRESH MAGGOT, DRIED MAGGOT (Hermetia illucens) AND COMMERCIAL FEED ON THE GROWTH OF CATFISH (Clarias gariepinus)
Catfish (Clarias gariepinus) is a freshwater fishery commodity that has bright prospects for development. Steps to address the problem of relatively high feed prices can be reduced by seeking alternative feeds. Maggot (Hermetia illucens) can be utilized as an alternative feed ingredient that meets the requirements as a protein source without relying on commercial feed. The purpose of this study is to analyze the effect of feeding combinations of fresh whole maggot, dried maggot, and commercial feed on catfish growth. This study used an experimental method. The design pattern used was a Completely Randomized Design (CRD) tested using Analysis of Variance (ANOVA) with a 95% confidence level, using six treatments and three replications: P0 (100% commercial feed), P1 (50% commercial feed + 50% fresh maggot), P2 (50% commercial feed + 50% dried maggot), P3 (50% fresh maggot + 50% dried maggot), P4 (25% CF + 25% FM + 50% DM), P5 (25% CF + 50% FM + 25% DM). The commercial feed, fresh maggot, and dry maggot were mixed directly according to the treatment and then given to the fish. The results showed that the combination feed significantly affected absolute length growth, absolute weight growth, specific growth rate (SGR), and survival rate (SR), but did not have a significant effect on feed utilization efficiency and feed conversion ratio (FCR). Treatment (P2) with 50% commercial feed and 50% dried maggot provided the best growth results with an average absolute length of 4.69 cm and absolute weight of 5.29 g, specific daily growth of 1.69%/day, and fish survival rate of 81%.
EFFECTIVENESS OF VARIOUS METHOD OF KETAPANG LEAF EXTRACTION (Terminalia catappa) TO PREVENT Aeromonas hydrophila BACTERIAL INFECTION IN NILE NILE FISH (Oreochromis niloticus) CULTIVATION
Bacterial diseases caused by (Aeromonas hydrophila) are one of the main obstacles in the cultivation of tilapia (Oreochromis niloticus), especially in intensive cultivation systems, the problem can be overcome with natural immunostimulants from the leaves of tilapia (Terminalia catappa). This study aims to analyze the effectiveness of various methods of extraction of tacumber leaves in feed on the immune response, growth, and survival of tilapia tested with A. hydrophila. The study used a complete randomized design (RAL) with five treatments and three replicates, namely positive control (feed without extract, P1), negative control (feed without extract, P2), feed with extract in the form of flour (P3), feed with extracted form of decoction (P4), feed with extract in the form of porridge (P5). The amount of extracts added is 5%. On the 46th day, infection A .hydorphila was carried out in all treatments except in P2. Parameters observed included survival rate (SR), feed conversion ratio (FCR), specific growth rate. Water quality was measured once every 10 days from days 1 to 45 while total bacterial media, hematology parameters, phagocytosis activity were observed on day 60. The results showed that the addition of ketapang leaf porridge extract (P5) had a real effect (p<0.05) on the value of SR 91.11%, FCR of 1.06, and specific weight growth rate of 3.71%/day. Total bacterial media (30.5×10³ CFU/mL), as well as increased immune response as indicated by Erythrocyte values of 2.10×10⁶ cells/mL, leukocyte values of 28.1× 104 cells/ml, leukocyte differential values (25% neutrophil cells, 7.33% monocytes, and 67.67% lymphocytes), hemoglobin of 6.8 g/dl, hematocrit of 30.48% and phagocytosis activity of67.6%, but no real effect (p>0.05) to specific long-term growth rate parameters. Thus, the method of burying ketapang leaves is effectively used as a natural immunostimulant in tilapia feed to increase resistance to A. hydrophila infection
Copyright (c) 2025 Journal of Fish Nutrition
THE EFFECT OF A COMBINATION OF DUCK EGG YOLK, SILK WORMS (Tubifex SP.), AND PELLETS ON THE GROWTH AND SURVIVAL RATE OF GIANT GOURAMI FRY (osphronemus gouramy)
This study aims to analyze the effects of combining duck egg yolk, silk worms, and pellets on the growth and survival rates of gourami fry. The method used is an experimental method with a Completely Randomized Design (CRD) involving 6 treatments and 3 replications. The treatments tested are: P0: control (silk worms), P1: 100% pellets, P2: combination of 25% silk worms + 75% pellets, P3: combination of 25% silk worms + 75% duck egg yolk, P4: combination of 50% silk worms + 50% pellets, P5: combination of 50% silk worms + 50% duck egg yolk. The parameters tested include feed consumption rate, absolute weight, absolute length, specific weight gain, specific length growth, feed conversion ratio, feed efficiency, and survival rate. The data were then analyzed using analysis of variance (ANOVA) at the 95% significance level. The results showed that the effect of providing the combination of feed in the form of silk worms, duck egg yolk, and pellets had no significant effect (p>0.05) on absolute weight, which ranged from 0.70-0.83 g, absolute length ranged from 2.43-2.63 cm, specific weight growth rate ranged from 1.74 -2.08 %/day, specific length growth rate ranged from 6.08-6.50 %/day, and survival rate ranged from 66.7-83.3%. However, there were significant differences (p<0.05) in the feed consumption rate, with the highest rate in P1 at 7.91 g/fish and the lowest in P3 at 5.21 g/fish. Feed efficiency was highest in P3 at 66.40%, while the lowest was in P1 (100% pellet) at 37.79%. The highest feed conversion ratio was observed in P1 at 2.70, and the lowest in P3 at 1.55. The combination of silk worms, duck egg yolk, and pellets resulted in similar growth for weight, length, specific weight, and specific length. However, for feed conversion ratio and feed efficiency, the highest results were obtained with a combination of 25% silk worms and 75% duck egg yolk.
UTILIZATION OF MAGGOT FLOUR (Hermetia illucens) FERMENTED USING ASPERGILLUS NIGER IN FEED FOR THE GROWTH OF GOURAMI FISH (Osphronemus goramy) JUVENILE
This study evaluated the utilization of maggot flour fermented with Aspergillus niger in gourami fish seed feed. The research was conducted using a one-factor Complete Random Design (RAL) with five treatments and three replications. The treatment used was feed without fermented maggot flour (P0), feed containing 25% fermented maggot flour (P1), feed containing 50% fermented maggot flour (P2), feed containing 75% fermented maggot flour (P3), and 100% feed containing fermented maggot flour (P4). Fish with an average initial weight of 2.93 ± 4.00 g were stocked into 15 net cages (1 × 1 × 1 m³) at a density of 25 fish per cage. The fish were fed test feeds at 10% of their body weight, 3 times daily (08:00, 13:00, and 17:00), for 56 days. Feed digestibility was assessed in an aquarium (60 × 40 × 40 cm³) at a dense stocking density of 10 fish per m³. The test feed contained 0,5 % Cr2O3. The results indicated that the inclusion of 75% fermented maggot meal yielded the best outcomes, with feed digestibility of 74.36%, protein digestibility of 88.76%, feed efficiency of 46.10%, protein retention of 33.38%, specific growth rate of 3.29% per day, and a survival rate of 100%.
THE EFFECT OF FEED VARIATION ON THE REPRODUCTIVE EFFICIENCY OF GUPPY FISH (Poecilia reticulata)
The purpose of this study is to analyze the impact of varying types of feed on the reproductive performance of guppy fish. The method used is an experimental method with a Completely Randomized Design (CRD) consisting of 4 treatments (P0: Pellet, P1: Bloodworms, P2: Mosquito larvae, P3: Water fleas) and 3 replications. The parameters tested include gonadal maturation, larval count, larval sex ratio, number of breeding adults, gestation period, survival rate, and water quality. The data obtained were tested for normality, and non-normal data were analyzed using the Kruskal-Wallis test. Normal data were analyzed using ANOVA at a 5% significance level, followed by Duncan's test at a 5% significance level. The results showed that varying feed types had no significant effect (p > 0.05) on the gonadal maturation parameter (ranging from TKG 3 to 4), larval sex ratio (ranging from 29.6% to 60.4%), and the number of breeding adults (ranging from 66% to 100%), as well as the gestation period (ranging from 12 to 17 days). However, the different feed types had a significant effect (p < 0.05) on the number of larvae (ranging from 8 to 22) and survival rate (ranging from 43.6% to 90.6%). It can be concluded that bloodworms and mosquito larvae provide the best results for the number of larvae and survival rate parameters.
Copyright (c) 2021 Journal of Fish Nutrition
ASSESSMENT OF ENVIRONMENTAL SUITABILITY FOR SPINY LOBSTER (Panulirus homarus) AND RABBITFISH (Siganus sp.) POLYCULTURE BASED ON PHYTOPLANKTON COMMUNITY STRUCTURE IN FLOATING NET CAGES
This study aims to analyze the composition and abundance of phytoplankton as a bioindicator of environmental suitability in a polyculture farming system of spiny lobster (Panulirus homarus) and rabbitfish (Siganus sp.) in floating net cages (FNC). Phytoplankton plays an important role in maintaining aquatic ecosystem stability and reflects water quality conditions through changes in community structure. Sampling was conducted at three points around the FNC using a purposive sampling method. The observed parameters included abundance, diversity, dominance, and evenness indices, which were analyzed descriptively to assess the condition of the waters. The results show that phytoplankton abundance falls within the eutrophic category, with moderate diversity (H’), high evenness (E), and low dominance (D). One external factor contributing to eutrophication in aquatic environments is aquaculture activities using FNC systems. Phytoplankton from the class Bacillariophyceae were found in the highest numbers, particularly the species Rhizosolenia sp. and Synedra sp. Several studies indicate that both species are naturally found in the stomach contents of lobsters and serve as natural feed for P. homarus and rabbitfish. Values of physical and chemical water quality parameters indicate that the FNC Ujung Betok waters remain suitable for aquaculture activities. Based on bioindikator analysis and the physical–chemical conditions of the waters, the Ujung Betok FNC is suitable for the polyculture farming of spiny lobster and rabbitfish.
GROWTH AND SURVIVAL OF TILAPIA (Oreochromis niloticus) USING A COMBINATION OF PELLETS AND LEMNA (Lemna perpusilla)
This study aims to examine the growth and survival rate of tilapia fish fed a combination of pellets and Lemna perpusilla. The test animals used in this study were tilapia (Oreochromis niloticus) raised in concrete ponds using a complete randomized design (CRD) with treatments consisting of 100% L. perpusilla + 0% pellets, 25% L. perpusilla + 75% pellets, 50% L. perpusilla + 50% pellets, and 0% L. perpusilla + 100% pellets. The results showed that the highest absolute weight gain in fish fed mixed feed was observed in the 0% L. perpusilla + 100% pellet treatment, while the highest survival rate in this study was observed in the 0% L. perpusilla + 100% pellet treatment, which was 95%. The results of the analysis of variance for absolute weight growth between treatments showed a significant effect (P<0.05), while the survival rate showed no effect (p>0.05). In conclusion, feeding a combination of pellets and L. perpusilla had a significant effect on specific growth rate. The highest specific growth rate was observed with 25% L. perpusilla combined with 75% pellets, while the survival rate of tilapia fed a combination of pellets and L. perpusilla during the rearing period was not significantly affected. The highest survival rate was shown by feeding 50% L. perpusilla combined with 75% pellets and 25% L. perpusilla combined with 50% pellets.
ANALYSIS OF LENGTH-WEIGHT RELATIONSHIP OF TILAPIA (Oreochromis niloticus) FRY AS GROWTH BIOINDICATOR DURING THE EARLY CULTIVATION STAGE
This study aims to analyze the length-weight relationship of Nile tilapia (Oreochromis niloticus) seeds, specifically black tilapia and red tilapia, as growth bioindicators during the early rearing stage. The length-weight relationship was analyzed using an allometric model, along with a comparison of absolute and specific growth rates between the two varieties. The research was conducted at the UPTD Fish Seed Center in Bontang City, East Kalimantan, with the seeds being reared for 30 days in tarpaulin ponds. The results showed that black tilapia had a stronger length-weight relationship compared to red tilapia, with a negative allometric growth pattern observed in both varieties. Black tilapia exhibited higher absolute growth rates, while red tilapia had a higher specific growth rate. The feed conversion ratio (FCR) indicated better feed efficiency in red tilapia. This study is expected to serve as a reference for the management of tilapia farming, particularly in the seed stage, by considering the differences in strain and feed utilization efficiency.
THE EFFECT OF FEEDING COMMERCIAL FEED WITH DIFFERENT PROTEIN LEVELS FROM DIFFERENT PRODUCERS ON SURVIVAL AND GROWTH OF HOVEN’S CARP (Leptobarbus hoevenii)
Hoven’s carp is a local freshwater fish commodity that has high economic value, but its availability in nature is decreasing. Protein is a key element needed for growth and health in all types of fish. This study aims to determine the effect of giving commercial feed with different protein levels and determine the right protein level for the survival and growth of Hoven’s fish (Leptobarbus hoevenii) fingerlings. The method used in this research was an experimental method giving commercial feed with different protein levels, namely P18-20, P29, P35, and P40. The experimental design used a Completely Randomized Design (CRD) consisting of four treatments and three replications. Parameters observed included survival, total length growth, absolute weight growth, Specific Growth Rate, feed utilization efficiency, and feed conversion ratio. The results showed that giving commercial feed with different protein levels did not have a significantly different effect on survival (P>0.05). However, it gave a significantly different effect on total length growth, absolute weight growth, specific growth rate, feed conversion ratio, and feed utilization efficiency (P<0.05). Total length growth of P35 2.47 cm, absolute weight growth of P35 6.69 g, specific growth rate of P35 1.57%, feed utilization efficiency of P35 68.99%, and feed conversion ratio of P35 1.46 showed the best values. The best treatment was found in feed P35 using the FF–999 brand produced by PT. Central Proteina Prima with a protein content of 35%, seen from the highest total length growth, absolute weight growth, specific growth rate, and feed utilization efficiency, as well as the lowest feed conversion ratio.
EFFECTIVENESS OF Chaetoceros sp. CULTURE AS LIVE FEED FOR PEARL OYSTER: COMPARISON OF LABORATORY AND FIELD METHODS
Chaetoceros sp. is an important microalga in aquaculture that requires culture system optimization to enhance productivity and production efficiency. This study aimed to analyze the growth dynamics of Chaetoceros sp. in laboratory and outdoor culture systems and evaluate growth parameters and water quality factors affecting culture productivity. The study employed a completely randomized design with two treatments: laboratory culture (environmental control) and outdoor culture (natural conditions). Parameters observed included population density, relative growth, specific growth rate, doubling time, and water quality parameters (temperature, pH, salinity, light intensity) over 4 days of cultivation. Laboratory culture demonstrated superior performance with maximum population density of 3.60 × 10⁶ cells/ml, relative growth of 105.7 ± 12.27, specific growth rate of 19.7 ± 1.8%, and doubling time of 3.88 ± 0.34 days. Outdoor culture yielded maximum density of 3.28 × 10⁶ cells/ml, relative growth of 87.1 ± 12.44, specific growth rate of 16.9 ± 2.0%, and doubling time of 4.49 ± 0.51 days. Both methods achieved optimal exponential phase on day 3. Water quality parameters showed better stability in laboratory culture with lower variability. Strict environmental control in laboratory culture can reduce growth variability and improve predictability of Chaetoceros sp. culture results. Although laboratory culture is more technically efficient, outdoor culture remains viable for community applications considering cost efficiency and environmental sustainability.