Now showing items 1-9 of 9

    • magazineArticle

      DNA markers help manage Nile tilapia stocks 

      MRR Eguia & N Taniguchi - Global Aquaculture Advocate, 2006 - Global Aquaculture Alliance
      Determining changes in the genetic diversity of selected hatchery stocks through DNA-level polymorphisms analysis provides aquaculturists with a means to monitor inbreeding, control loss of genetic diversity, and achieve sustainable levels of genetic gain in the development of improved stocks. Tests with selected and domesticated tilapia stocks in the Philippines revealed variability between marker system results.
    • Conference paper

      Expressions of molt-inhibiting hormone (MIH) and extracellular signal-regulated kinase (ERK) during the molting stages of the giant mud crab, Scylla serrata 

      KC Perez, JJ Huervana, MR Eguia & MC Ablan-Lagman - In Proceedings of the DLSU Research Congress 2017, De La Salle University, Manila, Philippines, June 20-22, 2017, 2017 - De La Salle University
      Survival and growth of mud crabs and any other crustaceans depend on molting. Molting is influenced by several hormones, two of which are Molt-Inhibiting Hormone {MIH} and a molt promoting hormone, the Extracellular Signal-regulated Kinase (ERK). Controlling and synchronizing the molting of the crabs would be a big boost to the mud crab industry, especially in the production of soft shell crabs. The best way to control molting would be to stock juvenile crabs of the same molting stage together. In this study, hormone expressions were analyzed using quantitative Real-Time Polymerase Chain Reaction (1RT-PCR). Molt stages of 36 juvenile S. serrata were established based on MIH and ERK expression levels that was analyzed using Principal Component Analysis (PCA). One group of six individuals had MIH value equal to zero and presumed to be in the PR stage. The rest of the crabs had values for MIH and were presumed to be in the PM-IM stage. The value of ERK for the PM-IM stage was higher at 24.79 than in the PR stage at 21.67. Based on the data gathered, morphological markers may now be identified to standardize hormone expression. This would be the first study concerning the comparison of hormones during molting.
    • Conference paper

      Morphological development and survival of Philippine silver therapon larvae, Leiopotherapon plumbeus (Kner, 1864) reared under different feeding schemes 

      JAP Añano & MRR Eguia - In Proceedings of the DLSU Research Congress 2016, De La Salle University, Manila, Philippines, March 7-9, 2016, 2016 - De La Salle University
      Philippine silver therapon, Leiopotherapon plumbeus, locally known as ayungin, is an endemic fish species in the country. The demand for silver therapon remained high despite the decline of its population and commercial catches. Taking into account the potential of this species for stock enhancement, this study focused on developing an initial feeding strategy necessary to provide potential L. plumbeus juveniles for aquaculture. The experiment conducted was a short duration 10-day feeding experiment which used different feeding schemes utilizing live food organisms [Brachionus (B), Moina (M), co-fed with BM, Chlorella (C) and filtered lake water (L)]. Morphometric measurements were evaluated to assess growth performance of larvae among different feeding schemes. Survival rate was determined at the end of feeding experiment at 9 DAH (days after hatching).

      Growth parameters of L. plumbeus larvae reared under different feeding schemes showed significant differences starting at 5 DAH (P < 0.05) onward. After a total of 10 days, a significant decline in fish larval samples was observed under two feeding schemes (C and L). BM has a significant higher rate of survival (18.07 ± 7.09%) compared to other treatments. B. rotundiformis (15-20 mL-1) can be considered as a starter food for silver therapon larviculture and M. micrura (5-10 mL-1) can be utilized during an assumed co-feeding phase at 6 DAH.
    • Conference paper

      Optimization of feeding and growth conditions for hatchery-bred larvae of indigenous Philippine silver perch, Leiopotherapon plumbeus (Perciformes: Terapontidae) 

      JA Añano, F Aya, MN Corpuz & MRR Romana-Eguia - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The Philippine silver perch, locally known as ayungin, is an endemic fish species and is considered as a potential candidate for aquaculture and for stock enhancement. However, high mortality associated with early larval stages presents a significant bottleneck to its latent commercialization. Culture experiments considered interactions among prey proportions, growth conditions and their consequences on fish growth performance and survival. Two phases of the experiment were conducted: (1) a short duration feeding trial utilizing different prey proportions of Brachionus calyciflorus and Moina macrocopa and (2) an indoor larval rearing technique that ensured optimum growth and survival of juveniles. Findings of this research will be used to propose an efficient rearing strategy addressing the aquaculture of this indigenous species.
    • Book

      Pag-aalaga ng tilapya 

      RV Eguia & MRR Eguia - 2007 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Series: Aquaculture extension manual; No. 22
      The manual discusses tilapia culture methods in concrete tanks, netcages, and fishponds. It details the species of tilapia cultured in the Philippines, which include Oreochromis nilotucus, O.mossambicus, O.aureus. It covers the following: site selection; construction of netcages and its modules; fishpond construction and pond preparation; criteria for fry selection; stocking; netcage and pond management including water quality management; and harvest. The manual also lists the agencies involved in tilapia research and development in the Philippines; defines some technical terms in a glossary, and lists some useful references.
    • Book

      Pagpapaanak ng tilapya 

      RV Eguia & MRR Eguia - 2007 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Series: Aquaculture extension manual; No. 23
      This 52-page revised edition of the 1996 manual, discusses the spawning of tilapia in concrete tank hatcheries, hapa hatcheries in ponds and lakes and the hatchery operations of tilapia.
    • Book

      Pagpapaanak o pagpaparami ng tilapya 

      RV Eguia, MRR Eguia & ZU Basiao - 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Series: Aquaculture extension manual; No. 23
      The manual discusses spawning tilapia (Oreochromis spp) in concrete tank hatcheries, hapa hatcheries in ponds and in lakes in the Philippines. Also included in the manual are a list of agencies involved in tilapia research, a glossary of technical terms, and useful references.
    • Article

      Reproductive performance of four red tilapia strains in different seed production systems 

      MRR Eguia - The Israeli Journal of Aquaculture-Bamidgeh, 1996 - Society of Israeli Aquaculture and Marine Biotechnology
      The reproductive efficiency of one Thai red tilapia strain (NIFI) and three genetically diverse Philippine red tilapia strains (BFS, FAC, and PF) were compared. Breeders from each strain were stocked separately in land-based concrete tanks and lake-based hapa net cages or fine-meshed net cages at densities of 4 males:12 females per enclosure. Spawning activity, seed (egg and fry) production and hatchability data from the four strains in each hatchery system were monitored once every three weeks for twelve months.

      Results showed that seed production in all strains was lower in cages than in tanks. Daily mean seed production in the land-based hatchery system was highest at 12.41 per spawner for FAC followed by NIFI (11.18), BFS (9.49) and PF (5.56). In the hapa net cages, BFS produced 2.19 eggs and fry per female daily while NIFI, FAC and PF gave daily harvests of 1.40, 1.18 and 1.14 eggs and fry per spawner. Analysis of variance showed that seed production was significantly influenced by the strain, type of hatchery system and the interaction between the two factors.
    • magazineArticle

      Sustainable tilapia farming: a challenge to rural development 

      JD Toledo, BO Acosta, MRR Eguia, RV Eguia & DC Israel - Fish for the People, 2008 - SEAFDEC Secretariat
      The availability of improved Nile tilapia strains is a major factor that has opened up new avenues for renewed growth in the tilapia industry especially in the rural sector. This was hailed as a positive development in the tilapia industry because it promised opportunities for improvement of the rural economy. Although this article discussed the development of tilapia aquaculture in the Philippines, other countries can learn from this experience specifically in addressing challenges related to rural development.