Sea bass culture

This brochure provides a practical guide to the hatchery, nursery, and grow-out culture of sea bass (Lates calcarifer), a high-value food fish cultivated in Southeast Asia. It outlines best practices for broodstock selection, induced spawning, larval rearing, and nursery management to ensure high survival and growth rates. Grow-out methods in ponds and cages are detailed, including optimal stocking densities, feeding regimes, and water management. A sample profitability analysis demonstrates the economic viability of sea bass farming, showing a high return on investment under proper culture conditions

AQD Matters 2024 November - December

In this issue: 1) Lab-grown seedlings boost farm growth multiple times; 2) Government collaboration, research infrastructure highlighted at PTAC Meeting; 3) Freshwater aquaculture training for Southeast Asian member countries; 4) SEAFDEC/AQD caps 2024 with a festive white Christmas celebration; 5) Multi-species freshwater hatchery to boost aquaculture in CARAGA region; 6) Milkfish, giant freshwater prawn thrive in same pond; 7) Sustaining aquaculture advancements in Southeast Asia: JIRCAS and SEAFDEC strengthen ties, map future plans; 8) Training course held for seaweed micropropagation, nursery; 9) SEAFDEC/AQD staff shares strategies to improve info dissemination; 10) SEAFDEC convenes 47PCM back-to-back with 27FCG/ASSP; 11) Researchers succeed in growing slipper lobster juveniles; 12) Does size matter? Female mate choice in freshwater gob

Investigating stocking density, culture duration, and the combination ratio of artificial feed and fresh feed for mangrove crab Scylla serrata megalopae reared in pond-based net cages

To address the crablet supply shortage for grow-out ponds, two experiments were conducted. The first aimed to identify the optimal combination of stocking density (SD) and culture duration (CD), while the second utilized this combination to determine the most effective ratio of artificial feed (F) to mussel meat (M) for nursery rearing of mangrove crab (Scylla serrata) megalopae into crablets. Each pond-based net cage (1 m2 area) was provided with 1 unit each of shelter and feeding tray. The first experiment assessed four SDs (50, 100, 200, and 300 ind.m−2) at two CDs (3 and 4 weeks). Results showed that crablets at 50 ind.m−2 had carapace width (CW) of 17.3 mm and final body weight (FBW) of 0.65 g after 4 weeks while the highest specific growth rate (SGR) of 19%/day was observed at 3 weeks. Although survival rates were higher (80–84%) at SD 50, 100, and 200 ind.m⁻2, a higher final harvested number of crablets was achieved at higher SD 200–300 ind.m⁻2 of 162 and 215 ind.m−2, respectively. Using the SD 200 ind. m⁻2, the second experiment evaluated 50F:50 M, 70F:30 M, 80F:20 M, and 100F alone on megalopa reared for 3 weeks. Results indicated that the 70F:30 M treatment obtained the highest SR of 69.9%, FBW of 0.28 g, CW of 12 mm, and SGR of 21.33%/day (p > 0.05). Our results indicate that a SD of 200–300 ind.m2 and a feed ratio of 70F:30 M for 3 weeks are recommended for optimal growth and maximizing crablet production of Scylla serrata megalopae in nursery rearing.This research is financially supported by the Southeast Asian Fisheries Development Center Aquaculture Department (SEAFDEC/AQD) with the reference code TV-01-C2021D/ 5309-T-TV-C0121D

Nursery culture of mangrove crab megalopae (Scylla serrata) in pond-based net cages

This manual, titled “Nursery Culture of Mangrove Crab Megalopae (Scylla serrata) in Pond-Based Net Cages,” is part of SEAFDEC/AQD’s effort to assess the potential of using megalopae as the starting stock in pond-based net cage nurseries. The method is intended to enhance survival rates during the grow-out stage. Given the increasing availability of hatchery-reared megalopae and the high cost of crab instars, the manual also evaluates the cost-effectiveness and practical advantages of using megalopae in nursery operations. Hatchery-sourced megalopae offer key benefits over wild-caught ones, including consistent supply, environmental sustainability, disease-free status, species certainty, and stable pricing. This approach could help increase hatchery production cycles and lower overall production expenses in the crab farming industry. The manual covers various aspects, including mangrove crab biology, site selection, pond preparation, nursery management, packing and transport procedures, and economic analysis. The authors hope this resource will serve as a practical guide for crab farmers, farm managers, aquaculture professionals, technicians, and students by providing essential knowledge on science-based aquaculture practices.The authors would like to express their sincere appreciation to the following: (1) Southeast Asian Fisheries Development Center Aquaculture Department (SEAFDEC/AQD) for funding our study with reference code: DP-03-C2024D/5309-T-TV-C0324D; (2) the mangrove crab hatchery team, previously led by Dr. Sheryll Avanceña, for providing the megalopae used in this study; (3) the staff of SEAFDEC/AQD’s Dumangas Brackishwater Station—Ms. Roselie Cabatia, Mr. Ralen Depamaylo, Mr. Nestor Ardales, Mr. Felix Javero, Mr. Efren Gonzales, Mr. Federico Sotela and Mr. Roderix Escosa—for their valuable support during the sampling, sorting, and harvesting of crablets; (4) the AQD publication review committee for their thoughtful review of the manuscript; and (5) the Development Communication team, under the leadership of Mr. Rex Delsar Dianala, for the timely editing and layout of this manual

Effect of season, culture system, and stocking density on growth performance and limb loss in blue swimming crab (Portunus pelagicus) from instar to early juvenile stage

The study investigated the growth, survival rates, and limb loss occurrence of blue swimming crabs (BSC), Portunus pelagicus from crab instar to the early juvenile stage at different culture systems (outdoor tanks, net cages in ponds, and net cages in pens), and varying stocking densities (30, 50, and 100 individuals/m2). These variables were assessed during the wet and dry seasons for 21 days following a 2 × 3 × 3 factorial design. Survival showed a significant interaction between culture systems and seasons (p p > 0.05). Results showed that pond and pen systems, particularly at moderate densities (30–50 individuals/m2), yielded significantly higher growth, survival, and biomass production compared to tank systems (p P. pelagicus, contributing valuable insights for improving aquaculture protocols and supporting stock enhancement initiatives toward sustainable fisheries.This work was supported by Aquaculture Department, Southeast Asian Fisheries Development Center (SEAFDEC/AQD), and the Department of Science and Technology- Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development (DOST-PCAARRD) (Nr-01-C2014 T)

AQD Matters 2025 May - June

In this issue: 1) SEAFDEC/AQD makes waves at Aquaculture Philippines expo; 2) Trainees from Asia and Africa upskilled in sustainable fish feed development; 3) SEAFDEC/AQD welcomes BFAR-RFO 1 staff for training on milkfish culture; 4) Nat'l consultation on revised aquaculture standards for crustaceans; 5) 600k tiger shrimp larvae stocked in SEAFDEC/AQD ponds; 6) Scientists highlights Philippine freshwater prawn farming at Giant Prawn 2025 in China; 7) Aquaculturists in Asia-Pacific dive into sandfish culture training at SEAFDEC/AQD; 8) Pompano harvest at Igang Marine Station; 9) Routine health checkup for sea bass broodstock; 10) SEAFDEC/AQD shares seaweed research progress at international congress; 11) OJT Fellowship for trainees; 12) Chief, Deputy Chief attend 57th SEAFDEC Council Meeting; 13) Artificial diet boosts reproduction in Indian white shrimp; 14) SEAFDEC/AQD nets 2.7 tons of milkfish after 106 days of culture; 15) SEAFDEC/AQD Chief attends annual diplomatic reception at Malacañang; 16) Trainees from Quezon and Sulu learn abalone culture; 17) Farmers, fisherfolk from Laguna learn freshwater aquaculture; 18) SEAFDEC/AQD, Japanese experts map out future collabs; 19) SEAFDEC/AQD showcases aquatic animal health research, biosecurity measures in FAO-led study tour; 20) SEAFDEC/AQD, BFAR to collaborate with Blue Horizon seaweed projec

Mangrove crab culture

This brochure provides a comprehensive guide on the culture and farming of mangrove crabs (Scylla spp.), highlighting key aspects of hatchery, nursery, and grow-out operations. It covers species identification, broodstock selection, larval rearing techniques, and essential water quality parameters for successful crab farming. Detailed information on nursery site selection, stocking densities, feeding strategies, and transportation methods for crablets is also included. Additionally, the brochure presents an economic analysis of mangrove crab farming, outlining the costs, returns, and profitability based on monitored market prices. With proper management practices, mangrove crab aquaculture offers a sustainable and profitable venture for farmers and entrepreneurs in the industry

AQD Matters 2025 March - April

In this issue: 1) Dr. Takahiro Sajiki named SEAFDEC/AQD Deputy Chief; 2) SEAFDEC/AQD offers expertise to boost Palau's aquaculture development; 3) DA-BFAR Caraga partners with SEAFDEC on milkfish training; 4) Women's Month celebrated with Wellness Talk; 5) SEAFDEC/AQD leads int'l workshop on sustainable aquaculture, aquatic animal health; 6) New aquaculture feed mill rises with AQD's support; 7) Training course on giant freshwater prawn held; 8) SSS holds seminar and assistance caravan; 9) BFAR staff gain practical skills in milkfish aquaculture at SEAFDEC/AQD; 10) Training course aims to boost Thailand's milkfish production; 11) Fighting deadly shrimp diseases: Effectiveness of probiotics and disinfectio

Effects of restricted feeding rates on growth, production, and economics of Nile tilapia (Oreochromis niloticus) and giant freshwater prawn (Macrobrachium rosenbergii) polyculture in pond-based biofloc and traditional grow-out system

The combined effects of restricted feeding rates [50–75% apparent satiation (AS) and 100% AS] and culture systems [biofloc (BFT) and traditional pond system (TP)] on the growth, production, and economics of Nile tilapia-freshwater prawn polyculture were examined in a 2 × 2 factorial feeding trial for 120 days. Each treatment was carried out in triplicate following complete randomized design. Nile tilapia fingerlings (2.09 g) and freshwater prawn post larvae (PL20; 0.05 g) were stocked at an initial density ratio of 6:6 individuals/m2. Lower dissolved oxygen (DO) and higher Total Ammonia Nitrogen (TAN) and nitrite concentrations were observed in BFT system. Similarly, higher levels of DO were recorded in 50–75% AS-fed group, while TAN, nitrite, nitrate, and total suspended solids (TSS) were significantly higher at 100% AS-fed group. Culture system, feeding rate, and their interactions had significant effect on final body weight (FBW) and daily growth rate (DGR) of Nile tilapia. Lower FCR in Nile tilapia was noted in both BFT system and 50–75% AS-fed group. For freshwater prawn, the highest FBW and DGR were obtained in BFT system and fed 100% AS. However, survival rates and condition factor did not differ across all treatments for both species. Higher yield for both species and more large-size tilapia were obtained when fed at 100% AS. An increase in yield and significant improvement on the size distribution of prawns were also achieved in BFT system. Although both BFT and 100% AS have led to better performance, cost and return analysis have instead revealed better profitability using TP system and feeding rate of 50–75% AS. The lower cost of production in these treatments has economically compensated for the unfavorable growth, yield, and size distribution.The authors thank SEAFDEC Aquaculture Department for funding this study under the code TV-04-F2021T

The impact of indoor biofloc-based system on water quality, growth, and disease resistance of black tiger shrimp

The present study investigates the efficiency of an indoor biofloc-based system for the intensive culture of black tiger shrimp (Penaeus monodon). Water quality, growth performance, and disease resistance of black tiger shrimp (0.35 ± 0.07 g) were evaluated after 90 days of rearing in a zero-water exchange system. Shrimp were stocked at 180 individuals/m3 in nine 5-ton concrete tanks under three treatments: biofloc with molasses (M), biofloc with wheat flour (WF), and a control group reared in a conventional clear water (CW) flow-through system. The WF treatment resulted in significantly higher final weight and improved FCR compared to CW (p < 0.05). Survival was also significantly higher in both biofloc-based treatments despite elevated concentrations of total ammonia nitrogen, nitrite-nitrogen, and nitrate-nitrogen levels in the WF group (p < 0.05). Additionally, Kaplan–Meier survival analysis indicated that shrimp reared and challenged in the biofloc system exhibited better resistance to Vibrio parahaemolyticus (VPAHPND1212), as evidenced by higher survival rates. Although total hemocyte count, prophenoloxidase, and respiratory burst activities were not significantly different from the control group (p > 0.05), they were consistently elevated in the biofloc-based treatments. Overall, biofloc-based treatments, specifically WF, proved effective in biofloc formation, contributing to improved water quality, enhanced immune response and disease resistance, and superior growth performance in P. monodon. This study highlights the potential of indoor biofloc systems as a sustainable strategy for intensive P. monodon culture in indoor biofloc tanks.This work was supported by the Aquaculture Department, Southeast Asian Fisheries Development Center (NR-01-C2020T)