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An innovative biofloc technology for the nursery production of Pacific whiteleg shrimp, Penaeus vannamei in tanks
(International Network for Natural Sciences, 2022-10-09)
Nursery production of shrimp is usually done in small ponds; however, the use of small and circular tanks with plastic liners is gaining popularity. From an industry standpoint, there is still a need to assess how nursery systems can be of benefit to the shrimp production cycle. Hence, the use of small circular tanks coupled with the incorporation of biofloc technology was assessed in terms of its viability during the nursery production of the Pacific whiteleg shrimp, Penaeus vannamei. A 450m<sup>2</sup> plastic lined circular tank was installed and prepared for the stocking of P. vannamei postlarvae (PLs) at a density of 500 PLs per m<sup>2</sup>. Biofloc was produced and maintained throughout the nursery phase using brown sugar as carbon source at a carbon to nitrogen (C:N) ratio of 10. Water quality was monitored daily, while presumptive Vibrios were enumerated weekly. Sampling for growth was done at the 14<sup>th</sup> day post-stocking and weekly until harvest on the 30th day. The different water quality parameters were within optimum levels required for shrimp growth. Presumptive Vibrios were dominated by the yellow colonies. At the end of the nursery phase, there was 100% survival and the shrimp attained an average body weight of 1.26 g and a feed conversion ratio (FCR) of 0.43. Our results indicate that the use of small circular tanks with biofloc during the nursery production phase of whiteleg shrimp is feasible and can be incorporated in the grow-out culture of this shrimp species....
Molluscan aquaculture in the Philippines: A review
(Springer, 2023-04-25)
Molluscs are among the most valuable resources of the Philippines, an archipelagic country of 7,107 islands bounded by 36,000 km of coastline and 26.6 million ha of coastal waters. In 2020, production from mussels and ...
Grow-out culture of oyster Magallana bilineata (Röding, 1798) using pouches: A comparison of growth and survival in the river and earthen pond
(College of Agriculture and Food Science, University of the Philippines Los Baños, 2023-03)
Oysters are among the most in-demand aquaculture commodities in the Philippines and worldwide. With the decreasing culture area and the deteriorating water quality of oyster beds, there is a need to explore new culture ...
Motile aeromonads recovered from tilapia (Oreochromis niloticus) cultured in earthen ponds in the Philippines: Assessment of antibiotic susceptibility and multidrug resistance to selected antibiotics
(AquacultureHub Inc., 2022-07)
A total of 177 motile Aeromonas spp., comprised of A. hydrophila (n=162) and A. sobria (n=15), isolated from the water, sediment, gills and intestines of tilapia collected from the grow-out culture earthen ponds in the ...
Growth and carrageenan quality of sporophyte and gametophyte of the commercially important red seaweed Kappaphycus alvarezii
(Science and Technology Information Institute, Department of Science and Technology, 2022)
One dilemma facing the farming of the carrageenophyte Kappaphycus is the deteriorating quality of seedstock. Rejuvenating the commercial stocks using spores from reproductive wild parents that are sexually and asexually ...
Genomic analysis of Vibrio harveyi strain PH1009, a potential multi-drug resistant pathogen due to acquisition of toxin genes
(Elsevier, 2023-03-25)
In has increasingly been observed that viral and bacterial coinfection frequently occurs among cultured shrimp and this coinfection could exacerbate the disease phenotype. Here, we describe a newly discovered bacterial strain, Vibrio harveyi PH1009 collected from Masbate Island, Philippines that was found to be co-infecting with the White Spot Syndrome virus a sample of black tiger prawn, Penaeus monodon. The genome of V. harveyi PH1009 was sequenced, assembled, and annotated. Average Nucleotide identity calculation with Vibrio harveyi strains confirmed its taxonomic identity. It is a potential multi-drug and multi-heavy metal resistant strain based on the multiple antibiotic and heavy metal resistance determinants annotated on its genome. Two prophage regions were identified in its genome. One contained genes for Zona occludens toxin (Zot) and Accessory cholera toxin (Ace), essential toxins of toxigenic V. cholerae strains apart from CTX toxins. Pan-genome analysis of V. harveyi strains, including PH1009, revealed an “open” pan-genome for V. harveyi and a core genome mainly composed of genes necessary for growth and metabolism. Phylogenetic tree based on the core genome alignment revealed that PH1009 was closest to strains QT520, CAIM 1754, and 823tez1. Published virulence factors present on the strain QT520 suggest similar pathogenicity with PH1009. However, PH1009 Zot was not found on related strains but was present in strains HENC-01 and CAIM 148. Most unique genes found in the PH1009 strain were identified as hypothetical proteins. Further annotation showed that several of these hypothetical proteins were phage transposases, integrases, and transcription regulators, implying the role of bacteriophages in the distinct genomic features of the PH1009 genome. The PH1009 genome will serve as a valuable genomic resource for comparative genomic studies and in understanding the disease mechanism of the Vibrio harveyi species....
Inclusion of live mud polychaete (Marphysa iloiloensis) in the feeding regime improved the hatchery performance of domesticated Indian white shrimp (Penaeus indicus)
(Elsevier, 2023-03-07)
A 60-day feeding trial was conducted to evaluate the effect of inclusion frequency of hatchery-bred mud polychaete, Marphysa iloiloensis, as part of a combination diet on the reproductive performance and larval quality of ...
Effect of size grading on growth of yellow Pacific shortfin eel (Anguilla bicolor pacifica)
(Wiley, 2023-03-22)
Heterogeneous growth, which is common among farmed fish, can be remedied by size grading. This study focused on whether the size grading process, which is commonly practiced in aquaculture, improves the subsequent growth ...
A technical and economic evaluation of supplemental feeding strategies for Nile tilapia (Oreochromis niloticus L.) reared in lake-based cages
(AquacultureHub Inc., 2022-03)
Tilapia cage farming in eutrophic lakes uses low stocking densities since tilapias can thrive mainly on natural food or minimal supplementary feeding. For semi-intensive Nile tilapia cage culture, feeding strategies to ...
Biofloc-based nursery production system: Heeding the call towards a sustainable shrimp culture industry in the Philippines
(International Network for Natural Sciences, 2022)
The increasing global population resulted in intense pressure on the food production sectors to meet the rise in food demand. The aquaculture industry, which is one of the major food production sectors, provides opportunities ...