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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....
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 ...
Phylogenetic analysis of tilapia lake virus (TiLV) isolates from the Philippines based on partial genome segment 3 sequences
(College of Agriculture and Food Science, University of the Philippines Los Baños, 2022-03)
This study aimed to expand current knowledge on TiLV genetic diversity by sequence analysis of a portion of genome segment 3 of TiLV detected from the Philippines. This includes a recently deposited sequence in GenBank ...
Economic analysis of stake and rack-hanging methods of farming oysters (Crassostrea iredalei) in the Philippines
(Elsevier, 1998)
The cost efficiency of stake and rack-hanging methods of farming oysters are compared. Annual costs and returns data for both methods were obtained from a socioeconomic survey conducted in 1991 at the Aquaculture Department of the Southeast Asian Fisheries Development Center (SEAFDEC/AQD). On average, 14 kg m<sup>−2</sup> (shell-on) and 22 kg m<sup>−2</sup> (shell-on) were produced using the stake and rack-hanging methods, respectively. The translog cost function for 58 oyster farms was estimated using iterative seemingly unrelated regression (SUR). Statistical analysis indicates that the higher production from the rack-hanging method is significantly different (α=0.10) from the production using the stake method. The cost-efficient method varied based on production levels. At output levels less that 9044 kg (shell-on), the rack-hanging method had lower average cost per unit, and for higher production levels the stake method had the lower average costs. Similar conclusions were drawn from the marginal cost analysis. Results imply when production is less than 9044 kg, then the most efficient technology is the rack-hanging method and if production is greater than 9044 kg, the most efficient method is the stake method....
Use of rotifers-fed microalgal paste in the seed production of mangrove crab Scylla serrata in the Philippines
(Springer, 2022-09-09)
Despite the progress in the production of artificial diets for marine larvae, feeding during the early life stages of most aquaculture species still relies on live feeds such as rotifers. Advanced rotifer culture techniques ...
Estimating the economic benefits and costs of conserving marine protected area in San Jose, Antique, Philippines
(Silliman University, 2023-03-27)
The establishment of marine protected areas (MPAs) in the Philippines becomes a priority management strategy to conserve marine biodiversity and address the problem of declining marine resources. Economic studies can be a ...
Price relationships in Philippine milkfish markets: Univariate and causality analysis
(International Association of Aquaculture Economics and Management (IAAEM), 2006)
Uncertainties and lack of information on milkfish product prices, along with production-related problems with inputs, generally constrain efficient resource use in milkfish grow-out operations. Milkfish growers complain ...
The coral communities of Mararison Island, Culasi, Antique, Philippines
(University of the Philippines in the Visayas, 2006)
An assessment of the extensive fringing reefs surrounding Mararison lsland, Culasi, Antique was undertaken in 1994 to 1996 and in 1998 to provide scientific basis for management and enhancement of the island s resources ...
Protective immunity against viral nervous necrosis (VNN) in brown-marbled grouper (Epinephelus fuscogutattus) following vaccination with inactivated betanodavirus
(Academic Press, 2010)
Viral nervous necrosis (VNN) caused by betanodaviruses has been recently implicated in serious mortalities of groupers in the grow-out culture system. A safe and effective vaccine against this disease is urgently needed. ...
Change in Aplaya: resource use and responses to changing markets among fisherfolk in Honda Bay, Palawan
(University of San Carlos Publications, 2003)