Journal of Aquaculture Science

The Effect of Different Protein Concentration in Rice Bran Suspension as Feed on Cysts Production of Artemia salina

2023-08-29T16:00:45+07:00

Artemia salina is a natural food source known for its high nutritional quality. It is commonly used in larval rearing due to its ability to produce long-lasting cysts that can hatch at any time. These characteristics make A. salina very suitable for sustainable cultivation. In this study, the feed consisted of rice bran suspension enriched with Isolated Soy Protein (ISP) meal. The aim was to investigate the effect of different protein concentrations in the rice bran suspension feed on cyst production in A. salina broodstock. This study used a Completely Randomized Design (CRD) with five treatments and four replications. The treatments included P0 (without ISP meal, 25% protein concentration), P1 (ISP meal, 40% protein concentration), P2 (ISP meal, 45% protein concentration), P3 (ISP meal, 50% protein concentration), and P4 (ISP meal, 55% protein concentration). Data analysis was performed using ANOVA followed by Duncan's multiple range test. The results showed that variations in protein concentration with the addition of ISP flour had a significant effect (P < 0.05) on total cyst production and cyst production per broodstock of A. salina. The highest total cyst production (710.67 cysts/L) was achieved in P4 with a protein concentration of 55%, while the highest cyst production per broodstock (28.67 cysts/broodstock) occurred in P2 with a protein concentration of 45%.

Effect of Different Molasses Doses in Bacterial Growth (Commercial Probiotics)

2024-07-22T04:52:57+07:00

The study investigated the optimal dose of molasses for the cultivation of commercial probiotics containing Bacillus amyloliquefaciens and Bacillus subtilis. A two-month laboratory experiment was conducted at the Faculty of Fisheries and Marine Sciences, Jenderal Soedirman University, using a Completely Randomized Design (CRD) with four treatments: K (0 ppm), A (5 ppm), B (10 ppm), and C (15 ppm), each with three replications. The study measured optical density (OD) and bacterial growth over 48 hours. The results showed that Treatment C (15 ppm) produced the highest OD value (0.014), indicating substantial bacterial growth. However, it exhibited the slowest growth phase. In contrast, Treatment A (5 ppm) demonstrated the fastest growth phase and achieved the highest bacterial density throughout the study. This suggests that 5 ppm of molasses is ideal for rapid bacterial proliferation. Treatment K (0 ppm) resulted in the lowest OD (0.0042) and led to bacterial death by the end of the experiment, highlighting the necessity of molasses for bacterial survival and growth. In conclusion, a 5 ppm molasses dose (Treatment A) proved to be the most effective for promoting optimal bacterial growth and density, while higher doses resulted in slower growth, and no molasses inhibited bacterial survival

Growth and Survival of Seabass (Lates calcarifer) Cultured under Different Salinity Levels and Tank Colours

2025-01-03T09:00:46+07:00

This study investigated the interaction between salinity and container colour on survival, growth, and feed conversion ratio in barramundi (Lates calcarifer). This study used a Randomised Block Design (RCD), with juvenile sea bass (2-3 g weight, 5-6 cm length) stocked into a 70 litre aquarium. The study was conducted with a combination of three salinity levels (0, 15, and 30 ppt) and three container colours (blue, black, and orange). Each treatment consisted of 35 juveniles fed 40% crude protein pellets (0.7-1 mm) at 7% of biomass, three times a day for 28 days. There was a significant interaction between salinity and container colour on L. Calcarifers growth. Blue containers supported better weight gain at all salinity levels. Meanwhile, orange containers reduced the negative impact of high salinity on growth. Although, this interaction was not significant for length growth or feed conversion.

Stress Response and Pathology of Hybrid Groupers (Epinephelus lanceolatus × Epinephelus fuscoguttatus) Infested Trichodina sp. Maintained in Hatchery from Bali, Indonesia

2025-01-13T11:22:08+07:00

The demand for grouper fish continues to increase, with the Ministry of Fisheries' annual production target of 9,000 tons. However, intensive cultivation systems pose risks due to poor water quality, making grouper fish susceptible to disease and health problems. This study investigated the impact of Trichodina sp. infection on the blood glucose levels of hybrid grouper fish. The study was conducted in May 2024 by observing 30 fish and measuring blood glucose. The results showed that 20 fish showed glucose levels above the normal range (> 57.6 mg/dL), ranging from 61 to 114 mg/dL. In contrast, nine fish had glucose levels in the normal range (28.8 - 57.5 mg/dL), and one fish had low glucose levels of 26.7 mg/dL. High glucose levels in most fish indicate stress or metabolic disorders, possibly related to Trichodina sp. infestation. This parasitic infection can compromise the fish's immune system, making the fish more susceptible to disease. The results emphasize the need for effective parasite management and optimal water quality in intensive culture systems. To maintain grouper health and productivity, it is important to monitor water quality, control ectoparasites, and conduct further research on the long-term effects of these infections on blood glucose and overall health.

Natural Occurrence of Hybrid Koi and Mahseer in Artificial Ponds: Evidence of The Dangers of Releasing Non-Native Fish into The Wild

2025-04-08T08:49:15+07:00

The introduction of non-native species into new environments poses significant ecological risks, including the potential for hybridization with native species, leading to genetic pollution and the creation of hybrid species. This study investigates the natural occurrence of hybridization between koi (Cyprinus carpio var. koi), an ornamental species, and the native mahseer (Tor dourorensis) in an artificial pond in Padang, West Sumatra, Indonesia. The coexistence of these species over five years resulted in the emergence of hybrid offspring, which exhibited a blend of morphological traits from both parent species. Meristic and morphometric analyses revealed that the hybrids closely resembled mahseer in certain characteristics, particularly dorsal and caudal fin rays, while also displaying koi-like traits such as body color and fin shapes. The hybridization of these two species raises concerns about the genetic integrity of native mahseer populations and the potential ecological consequences. Hybrids may possess competitive advantages that could further threaten already vulnerable mahseer populations. The findings emphasize the urgent need for effective management strategies and regulations to prevent the release of non-native species into sensitive ecosystems. Public awareness campaigns and regulatory measures should be strengthened to mitigate the risks of hybridization and protect biodiversity in freshwater environments. This study serves as a critical reminder of the far-reaching consequences of introducing non-native species, particularly in regions with delicate ecological balances.

Effects of Dietary Coffee Husk Fermentation on The Growth of Catfish (Pangasianodon hyphophthalmus)

2025-02-13T09:59:16+07:00

Coffee husk fermentation (CHF) might be utilized as an alternative plant protein source. This research evaluated dietary CHF supplementation's effects on growth for striped catfish. This study consisted of five grade levels of CHF as a treatment. The treatments were P0 (without the addition of CHF), P1 (addition of 6% CHF), P2 (addition of 12% CHF), P3 (addition of 18% CHF), and P4 (addition of 24% CHF). The results determined that dietary CHF inclusion had no significantly different effect on specific growth rate (SGR) and feed efficiency (P > 0.05). However, the P1 group (6% CHF) produced the best protein retention (PR), which was significantly different from the control (P0) and other CHF treatments (P < 0.05). No significant differences were observed in survival rates among the treatments. The inclusion of CHF up to 24% in the diet was found acceptable, as it did not negatively impact the striped catfish’s overall health or growth performance. Although growth rate, feed efficiency, and survival did not significantly differ (P > 0.05).

The Effect of Adding Carrot Flour (Daucus carota) to Commercial Feed on Increasing the Brightness of the Body Color of Goldfish (Carassius auratus)

2025-04-08T10:31:22+07:00

One type of freshwater ornamental fish that is popular and in demand is the goldfish (Carassius auratus) because it has an attractive color that appears on its body, so food is needed that can trigger the appearance of attractive fish colors. The purpose of this study was to determine the effect of giving carrot flour and the right dose to increase the brightness of the color and growth of goldfish. The research design used was a completely randomized design (CRD) with an experimental method, four treatments, and three replications. The treatments tested were 0% carrot flour + 100% commercial feed (A), 5% carrot flour + 95% commercial feed (B), 10% carrot flour + 90% commercial feed (C), and 15% carrot flour + 85% commercial feed (D). The parameters observed were an increase in color brightness, absolute weight gain, feed conversion ratio, survival rate, and water quality (temperature, DO, and pH). The addition of carrot flour can improve the color brightness of goldfish but has no significant effect on absolute weight growth, feed conversion ratio, or goldfish survival. Water quality parameters measured during the study were still within a reasonable range for goldfish rearing.

Artificial Fertilization Techniques in Bronze Featherback (Notopterus notopterus): First Report and Preliminary Findings

2025-02-24T13:16:33+07:00

The Java-native bronze featherback (Belida Jawa), Notopterus notopterus, has been designated as a protected species under limited protection status by the Decree of the Minister of Maritime Affairs and Fisheries of Indonesia No. 83 of 2024, with captive breeding efforts undertaken for conservation and aquaculture to meet increasing consumer demand. This study provides a preliminary evaluation of artificial fertilization techniques in N. notopterus, focusing on hormone-induced spawning using Ovaprim™. The objective was to determine the effectiveness of hormone injection, optimal egg stripping timing, and hatching success under controlled water quality conditions. Two female broodstock received different dosages of Ovaprim™, and successful egg stripping was conducted after a 41-hour latency period. Fertilization rates of 30% and 11.23% were observed for the first and second females, respectively; however, hatching success remained extremely low at 0.52% for the first female, with no larvae hatching from the second. Despite maintaining water quality parameters such as temperature, pH, conductivity, and total dissolved solids within acceptable limits, the poor hatching rate suggests that additional factors, including ammonia concentration and dissolved oxygen levels, may have impacted embryonic development. This study establishes a foundational basis for artificial reproduction in N. notopterus, emphasizing the need for further research to optimize hormone protocols, sperm viability, and environmental conditions. These findings contribute to the advancement of aquaculture strategies for the conservation and sustainable management of this ecologically important species.

Back Matter

2025-04-29T13:10:36+07:00

Front Matter

2025-04-29T12:52:20+07:00