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  Growth, survival, and economics of milkfish (Chanos chanos) and giant freshwater prawn (Macrobrachium rosenbergii) in monoculture and polyculture systems in brackishwater earthen ponds 

  Dela Cruz, Marwin (Springer, 2026-05-28)

  Sustainable and effective production practices are needed to meet the growing global demand for food. Here, polyculture of milkfish and freshwater prawn with modified feeding scheme (POLY) was tested against monoculture of milkfish (MONO-Fish) and monoculture of freshwater prawn (MONO-Prawn) based on growth, survival, and economic parameters for 150 days. Each group was compared in triplicates. Milkfish juvenile at 1 indiv m^-2 and freshwater prawn at 10 indiv m^-2 were randomly distributed in brackishwater ponds each with an area of 20 m × 15 m and salinity at 5–10 ppt. Significantly higher FBW and DGR were observed in milkfish grown in POLY compared with MONO-Fish (P < 0.05) while growth rates of freshwater prawn did not vary between POLY and MONO-Prawn despite the absence of feeding for prawn in POLY group (P > 0.05). Survival rates and condition factors of both species in POLY were comparable with those in MONO-Fish and MONO-Prawn (P > 0.05). Higher feed intake was observed in POLY compared to MONO-Fish but FCRs were not significantly different (P > 0.05). In addition, higher yield for milkfish were recorded in POLY than MONO-Fish (P < 0.05), whereas yield for freshwater prawn was similar with MONO-Prawn (P > 0.05). Furthermore, there was no competition between the two species instead, a facilitative relationship was observed, with freshwater prawns positively influencing milkfish growth. The polyculture system incurred the highest production cost but also generated the highest net income, ROI, NPV, and DBCR (P < 0.05), making it more profitable than monoculture.
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  Predator-induced behavioral adaptation by hatchery-bred sandfish Holothuria scabra juveniles 

  Baylon, Roselyn ; Altamirano, Jon ; Santander - de Leon, Sheila Mae ; Monteclaro, Harold (National Shellfisheries Association, 2026-05-12)

  Wild populations of sea cucumbers are under threat from overexploitation driven by the increasing global demand for their dried products called trepang or beche-de-mer. Fortunately, hatchery techniques have been developed especially for the tropical sandfish Holothuria scabra. Farming and restocking programs, however, often overlook critical behavioral factors that can affect the survival of hatchery-bred sea cucumbers, particularly predation risk. This study investigated the predator-induced behavioral adaptations of hatchery-bred sandfish juveniles under tank conditions. The Conditioned sandfish (CS) group was exposed to a predator cue (i.e., caged crab) and a conspecific distress cue (i.e., injured sandfish) for 20 h daily (1200H to 0800H) over 5 days. In contrast, the naïve sandfish (NS) group was not exposed to such cues but presented only with empty cages. The findings suggest that the daily burying behavior of sandfish is not affected by short-term exposure (≤2 days) to predator and distress cues. But, extended exposure (≥3 days) elicited a significant antipredatory response in CS, prolonging their buried state from 8 h on Day 1 to 16 h by Day 5. Meanwhile, NS showed consistent burying periods throughout. Consequently, exposures to predator and distress cues resulted in significantly fewer sandfish juveniles emerging among CS. Following the release of predator crabs on Day 6, the CS group exhibited a significantly higher proportion of unharmed sandfish (63.00%) compared with NS group (45.83%). The NS had experienced higher mortality (20.83%) and injury rates (33.33%), whereas CS demonstrated lower mortality (8.33%) and injury rates (29.00%) after 24 h. These findings confirmed that sandfish are capable of associative learning and defensive behavioral adaptations in response to a potential predation threat, including extending their burying state. Regardless of treatment, sandfish preferred to bury beneath the cages, suggesting an innate tendency to shelter even in the absence of predation cues. For practical application, it is recommended that hatchery-bred sandfish juveniles (3–5 g) should be conditioned for 3–5 days prior to release at sites that offer natural refuge or, if necessary, provided with artificial shelter to increase their survival during restocking or farm-site releases.
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  AQD Matters 2026 March - April 

  Ebojo, Nicole Ann (Aquaculture Department, Southeast Asian Fisheries Development Center, 2026-05)

  In this issue: 1) Iloilo feed mill to boost aquaculture sector; 2) 289 seaweed farmers in Palawan receive quality seedlings; 3) Breeding breakthroughs highlighted at Viet Nam symposium; 4) Joint Batangas study records 850 ...
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  Genome sequencing and genome-wide analysis uncover candidate genes and loci linked to key production traits in the Philippine black tiger shrimp (Penaeus monodon) 

  Cadorna, Kreighton ; Aguinaldo, Zae-Zae ; de la Cruz, Miguel Paolo E.; Pasaquian, Hannah Mae E.; Corre, Valeriano L.; Estepa, Fe Dolores ; Amar, Edgar ; Maningas, Mary Beth B.; Lluisma, Arturo O. (Wiley, 2026-03-16)

  Penaeus monodon (black tiger shrimp) is a key species in aquaculture globally and in the Philippines. The selection and development of stocks with desirable production traits, such as enhanced growth and disease resistance, are critical for improving production. In this study, we leveraged a newly assembled, high-quality genome sequence from a Philippine population to perform genome-wide scans for SNPs associated with key production traits. Using cohort-based extreme phenotype GWAS (XP-GWAS), we identified variants linked to resistance against white spot syndrome virus (WSSV), body weight, and carapace length-to-abdomen length (CL/AL) ratio. Candidate genes previously implicated in immune defense and growth regulation were located within 1-Mb regions surrounding these variants, reinforcing their likely functional involvement and providing biological support for the associations. These findings highlight genomic loci and gene candidates of direct relevance to selective breeding, offering molecular markers with potential utility in stock improvement programs for P. monodon. These genomic data, alongside the identified polymorphisms, constitute a valuable resource for enhancement of production and selective breeding strategies in the Penaeid species, contributing to the improvement of shrimp aquaculture.
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  Dietary supplementation of Durvillaea potatorum fucoidan enhances the immune responses and improves survival of juvenile black tiger shrimp Penaeus monodon against white spot syndrome virus and acute hepatopancreatic necrosis disease 

  Faisan, Joseph P., Jr. ; Traifalgar, Rex Ferdinand ; de la Peña, Leobert D.; Corre, Valeriano L.; Pagapulan, Mary Jessa Bell B.; Gayosa, Vyenge Erre (Springer, 2026-03-09)

  The use of natural immunostimulants as alternatives to antibiotics has gained attention in aquaculture to mitigate disease impacts. In this study, we evaluated fucoidan extracted from giant bull kelp (Durvillaea potatorum) as a dietary additive in black tiger shrimp (Penaeus monodon). Four experimental diets containing increasing levels of fucoidan (0, 1.0, 2.5, and 5.0 g kg⁻¹ diet) were tested for their effects on growth, non-specific immune parameters, and survival against white spot syndrome virus (WSSV) and acute hepatopancreatic necrosis disease (AHPND)-causing Vibrio parahaemolyticus. After 30 days of feeding, fucoidan supplementation did not adversely affect shrimp growth or culture survival, even at the highest inclusion level (5 g kg⁻¹). Non-specific immunological indices, including total hemocyte count (THC), differential hemocyte count (DHC), phenoloxidase (PO) activity, plasma total protein (PTP), and plasma agglutination titer (PAT), were enhanced by fucoidan supplementation, with improvements observed even at 1 g kg⁻¹ relative to the control group. Activation of non-specific immunity translated into increased resistance against WSSV and AHPND, with the highest survival recorded in shrimp fed 5 g kg⁻¹ fucoidan, followed by 2.5 g kg⁻¹. In comparison, similar survival rates against WSSV and AHPND were observed in the unsupplemented control and 1 g kg⁻¹ fucoidan. Overall, this study demonstrates that dietary inclusion of D. potatorum fucoidan at 5 g kg⁻¹ effectively enhances immune responses and disease resistance in P. monodon without negatively impacting growth performance, highlighting its potential as a functional feed additive in shrimp aquaculture.

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