03 SEAFDEC/AQD External Publications

Genome sequencing and genome-wide analysis uncover candidate genes and loci linked to key production traits in the Philippine black tiger shrimp (Penaeus monodon)

Mon, 16 Mar 2026 00:00:00 GMT

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. 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.

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

Mon, 09 Mar 2026 00:00:00 GMT

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 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.

Growth performance and feed utilization of snubnose pompano (Trachinotus blochii) fed with Pirenella sp. as a dietary supplement

Fri, 06 Mar 2026 00:00:00 GMT

Growth performance and feed utilization of snubnose pompano (Trachinotus blochii) fed with Pirenella sp. as a dietary supplement Somblingo, Edgar; Baliao, Dan D.; Mamauag, Roger Edward; Ciacico, Albert; Villanueva, Roy Sustainable aquaculture requires the exploration of alternative, eco-friendly feed sources that can reduce production costs and dependence on commercial feeds. Pirenella sp., a common brackish water snail often considered a pest in aquaculture ponds, has potential as a natural feed ingredient for carnivorous fish species such as the snubnose pompano (Trachinotus blochii). This study assessed the growth performance, survival rate, and feed conversion ratio (FCR) of snubnose pompano fed with Pirenella sp. as a dietary supplement. Nine hapa nets (5 × 5 × 1.5 m) were installed in a brackish water pond and assigned to three treatments with three replicates each: 100% commercial feed (T1), 50% commercial feed + 50% snails (T2), and 100% snails (T3). Results showed that Treatment I achieved the highest growth performance, while Treatment II exhibited comparable outcomes, indicating that partial replacement of commercial feeds with Pirenella sp. did not significantly affect growth. Treatment III, which used only snails, produced markedly lower growth metrics (p<0.05). Survival rate remained at 100% across all treatments (P > 0.05). The lowest FCR (0.34) was recorded in Treatment II, suggesting optimal feed utilization. Although Treatment III had lower growth performance, it was the most cost-efficient due to the natural availability of snails. Overall, the incorporation of Pirenella sp. as a supplemental feed demonstrates potential for enhancing sustainability and reducing feed costs in pompano aquaculture while contributing to the biological control of pest snails in brackish water ponds.

Evaluation of cultivation potential and carrageenan properties of Hypnea sp. from Panay Island, Philippines

Tue, 10 Feb 2026 00:00:00 GMT

Evaluation of cultivation potential and carrageenan properties of Hypnea sp. from Panay Island, Philippines Matsuda, Ryuya; Faisan, Jr., Joseph; Sollesta-Pitogo, Hananiah; de la Peña, Leobert D. Hypnea is a cosmopolitan genus of red seaweeds and an important source of carrageenan worldwide. However, Hypnea species remain largely unutilized in seaweed aquaculture in the Philippines. This study aimed to evaluate the growth performance and carrageenan properties of an indigenous, unexploited Hypnea sp. collected from Panay Island and to compare them with those of the commercially cultivated Kappaphycus striatus. In a field cultivation experiment, Hypnea sp. showed significantly higher biomass (145.1 ± 53.7 g) than K. striatus (92.9 ± 10.3 g) up to day 28 (p < 0.001), while no significant difference was observed at days 36 and 43. The final yields were 181.0 ± 68.4 g for Hypnea sp. and 191.1 ± 33.0 g for K. striatus (p > 0.05). Semi-refined carrageenan extracted from the cultured Hypnea sp. exhibited gel-forming capacity, suggesting the presence of κ-carrageenan. However, both the viscosity and gel strength of Hypnea sp. (9.52 ± 3.53 cP; 148 ± 41.6 g cm⁻²) were significantly lower in K. striatus (70.9 ± 49.4 cP; 456 ± 201 g cm⁻²) (p < 0.001), indicating that Hypnea sp. possesses distinct carrageenan properties from conventional commercial seaweed. Although further development of carrageenan-based products tailored to its unique properties will be required for commercial utilization, these findings highlight the potential of Hypnea sp. as a candidate seaweed for aquaculture in the Philippines. Link to the electronic supplementary material.