Now showing items 379-398 of 1070

    • Article

      A farmer-oriented Nile tilapia, Oreochromis niloticus L., breed improvement in the Philippines 

      ZU Basiao, AL Arago & RW Doyle - Aquaculture Research, 2005 - Blackwell Publishing
      Opportunities for developing small-scale tilapia industry in the Philippines is hampered by the shortage of good-quality seeds and broodstock. Most small-scale farmers are dependent on distribution centres for improved tilapia seeds that are expensive and not sufficient to meet market demands. An option would be for farmers to develop their own tilapia breeds using simple procedures within their technical and financial resources. This option will also help sustain the diversity of locally adapted domestic stocks of tilapia. The Philippine tilapia production of ~ 122 316 MT can be increased by ensuring a stable supply of quality seeds and transferring suitable technology to fish farmers. The study was carried out in a tilapia hatchery/nursery pond in the Philippines to explore the potential for a farmer-based research on tilapia breed improvement using relatively simple artificial selection procedures.

      One generation of size-specific mass selection based on the early culling of large fry (collimation procedure) was applied on a Nile tilapia strain, Oreochromis niloticus L., in net cages set in a small earthen pond. Two episodes of directional selection were performed after initial removal of large fry at 21 days. Selection of parents and progeny testing were conducted in hapa and B-net cages set in earthen ponds. The selection resulted in a significant response of 8% for standard length and 29% for weight relative to the control. The crude estimates of realized heritability is ~ 16% for standard length and ~26% for weight comparable with similar studies conducted by other workers.
    • Article

      Fate and location of Vibrio anguillarum in tissues of artificially infected ayu (Plecoglossus altivelis) 

      K Muroga & MC de La Cruz - Fish Pathology, 1987 - Japanese Society of Fish Pathology
      Ayu (Plecoglossus altivelis) were infected with Vibrio anguillarum by a water-born method. At 6, 12, 18, 36, 38-45 (moribund stage) and 48 h (dead) after infection, fish were sampled to determine the fate and location of the bacterium in various tissues by viable cell count and the enzyme-labeled antibody technique (ELAT). V. anguillarum was first detected in the skin at 12 h by bacterial isolation. It appeared in the muscle, spleen and liver at 24 h, but was not isolated from the gills or intestine until 36 h or 38-45 h. The same trend in the fate of the pathogen was confirmed by ELAT, and the cells were found in dermal layer of the skin from the early stage (12h) of infection. Based on these observations it was concluded that the first colonization site of V. anguillarum in ayu was the skin.
    • Article

      Fatty acid composition of five candidate aquaculture species in Central Philippines 

      HY Ogata, AC Emata, ES Garibay & H Furuita - Aquaculture, 2004 - Elsevier
      Fatty acid composition was determined in five candidate aquaculture species, mangrove red snapper (Lutjanus argentimaculatus), two rabbitfish (Siganus guttatus and S. canaliculatus), coral trout (Plectropomus leopardus) and striped jack (Caranx fulvoguttatus) sampled in the Central Philippines. Special attention was paid to arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Total lipids of hatchery-produced eggs and newly hatched larvae of mangrove red snapper unexpectedly had equal levels of ARA and EPA. Ovarian polar lipids were subsequently found to have intermediate or high ARA (5.5–10.7%) and DHA (14.4–20.4%) levels but relatively low EPA levels (1.5–1.9%), consequently showing high ARA/EPA (4.4–6.0) and DHA/EPA (7.4–14.9) ratios in wild mangrove red snapper and rabbitfish (S. guttatus and S. canaliculatus). Similar trends were observed even in hatchery-reared mangrove red snapper, rabbitfish (S. guttatus) and coral trout. Not only ovary but also liver and muscle contained relatively higher ARA compared with EPA in mangrove red snapper, regardless of the sample source. ARA, EPA and DHA levels in the polar lipids of wild fry (whole body) ranged respectively from 3.2% to 4.0%, from 2.7% to 4.7% and from 23.5% to 27.6% with intermediate or high ARA/EPA (0.8–1.5) and DHA/EPA (5.9–8.8) ratios in mangrove red snapper, rabbitfish (S. canaliculatus) and striped jack. As overall traits, the five species in the Central Philippines appear to have intermediate or high ARA and DHA levels with low EPA level, consequently having high ARA/EPA and DHA/EPA ratios compared to species in high and temperate northern hemisphere. Thus, the present results indicate that ARA is not a minor component in the tropical species, suggesting that ARA may be nutritionally much more important for egg development and larvae growth in the tropical species than in cold water species. The information of the present study can be used as a guideline for development of appropriate broodstock and/or larval diets in the Philippines.
    • Article

      Feed preference of milkfish (Chanos chanos Forsskal) fry given different algal species as natural feed 

      JB Pantastico, JP Baldia & DM Reyes Jr. - Aquaculture, 1986 - Elsevier
      Acclimated milkfish fry (mean wet weight, 6.0 mg) were fed with unialgal cultures of five species of freshwater algae: Oscillatoria quadripunctulata, Chroococcus dispersus, Navicula notha, Euglena elongata and Chlorella ellipsoidea. In the first experiment, the filamentous blue-green alga, Oscillatoria, appeared most acceptable to milkfish fry throughout the growing period, while feeding milkfish fry with the unicellular species, Chroococcus, resulted in lower weights and survival. In the second experiment, increases in weight of milkfish fry fed with Oscillatoria alone or in combination with Chroococcus were comparable. However, a significant increase in survival was obtained with the combination feeding. A third experiment showed that high density cultures of Oscillatoria resulted in significantly large weight increments in all growth stages. The other algae tested did not support growth of milkfish fry.

      14C-Labeled algae of the same species were fed to milkfish fry. Significantly high assimilation retes were observed in almost all growth stages of milkfish fry with Oscillatoria alone or Chroococcus alone. Negligible amounts of Navicula, Chlorella and Euglena were assimilated.
    • Article

      Feed ration for different sizes of wild and hatchery-bred milkfish (Chanos chanos Forsskal) 

      NS Sumagaysay - Aquaculture Research, 1999 - Wiley-Blackwell
      Intensified production of fish involves stocking at high densities and the use of artificial feeds. These practices result in eutrophication and environmental degradation mainly because of feed wastage and fish excreta. To minimize waste, the maximum amount of feed consumed by fish must be known. Food consumption and utilization, however, may vary with the size and physical condition of the fish. Milkfish Chanos chanos Forsskal and some hatchery-produced fish, such as seabass Dicentrarchus labrax L. have been observed to have morphological defects that could affect normal food intake and utilization. Jaw abnormalities in hatchery-bred milkfish interfere with feeding and result in very slow growth. In the Philippines, milkfish fry for production in ponds and cages are caught from the wild or produced through artificial spawning. Studies have been conducted to estimate the feed ration for milkfish reared in brackish water ponds where natural food contributes significantly to the nutrition of the fish. In ponds and marine cages, where fish are largely dependent on artificial feeds, daily feed ration has to be estimated. This study determined the maximum feed ration for different sizes of wild and hatchery-bred milkfish based on assimilation of energy.
    • Article

      Feeding behavior and food preference of Penaeus monodon Fabricius with scrap Tilapia mossambica . 

      FD Apud, N Deatras & K Gonzales - Fisheries Research Journal of the Philippines, 1981 - Fisheries Research Society of the Philippines
      The time of day during which P. monodon feeds at different depth levels in earthen ponds, and its preference for three types of tilapia feeds (dry, fresh and fermented) were determined. It was observed that P. monodon concentrated at the bottom beds during the day and along the periphery of dikes during night-time, with a slight tendency to swim and feed towards the surface as darkness increased. P. monodon showed special preference for dried tilapia compared to fresh and fermented tilapia. P. monodon also showed adaptability to the platform method of feeding, especially during night-time.
    • Article

      Feeding ecology of silverperch, Terapon plumbeus Kner, and the impact fish-pens in Laguna de Bay, Philippines 

      M Kock, U Focken, H Richter, K Becker & CB Santiago - Journal of Applied Ichthyology, 2000 - Blackwell Publishing
      Aquaculture is an important factor in the fishery of Laguna de Bay in the Philippines; fish-pens and net-cages covered ≈10% of the lake surface in the late 1990s. The present study was carried out to assess the possible influences of aquaculture on a wild fish species, silverperch, Terapon plumbeus Kner, with a special emphasis on the feeding ecology of this fish. For the purposes of the investigation, 24-h samples were taken at 2-month intervals close to a fish-pen as well as in open water over a one-year period to acquire more information on this species. Significant differences in standard length and total weight were found between stations and sampling months. In open water, a mean standard length of 53.6 mm and a mean total weight of 4.2 g were found, whereas close to the fish-pen, the corresponding values were 57.6 mm and 5.4 g, respectively. The maximum mean standard length was attained around December 1996 and February 1997 (59.5 mm in open water; 66.1 mm close to the fish-pen), and the minimum was found in June 1996 (49.1 mm in open water; 46.2 mm close to the fish-pen). Noticeable differences were found in the food spectrum between the two sampling stations. Zooplankton, the major food source at both stations, was more important in the stomach content of fish in open water. The same was true for insects (i.e. chironomid larvae), although these did not make up such a large fraction of the diet. On the other hand, close to the fish-pen, aufwuchs-algae, phytoplankton and fish were more important. Generally, benthic organisms were consumed more frequently close to the fish-pen. Zooplankton was more important in the diet of smaller fish. In all size groups, the importance of zooplankton decreased during the rainy season.
    • Article

      Feeding live or frozen Moina macrocopa (Strauss) to Asian sea bass, Lates calcarifer (Bloch), larvae 

      AC Fermin & MEC Bolivar - The Israeli Journal of Aquaculture-Bamidgeh, 1994 - Society of Israeli Aquaculture and Marine Biotechnology
      Growth and survival of hatchery-reared sea bass, Lates calcarifer, larvae fed live or frozen Moina macrocopa were determined, In Experiment 1, Moina was fed to sea bass of different sizes: 3.6 mm, 5.5 mm and 7.6 mm standard length (SL) at stocking. After 15 days of rearing, fish with a mean initial SL of 3.6 mm had the highest specific growth rate (SGR, 18.82% per day). However, the mean survival rate was higher for fish with a mean initial size of 5.5 mm (64.76%). The mean number of ingested Moina increased with the fish body size and with the length of the feeding period. In a separate trial, sea bass larvae, regardless of size, ingested equal numbers of Artemia and Moina. In Experiment 2, live or frozen Moina was used as feed for 20-day sea bass fry (8.3 mm Sl and 13.4 mg) and compared to minced fish-by-catch (control). SGR and survival were significantly higher for fish fed live Moina. Sea bass fed frozen Moina and minced fish-by-catch had comparable growth and survival rates. Results showed that for hatchery rearing of sea bass, feeding Moina can effectively reduce the use of expensive Artemia. However, fry survival can be optimized by feeding live Moina to fish with a mean initial size of 5.5 mm SL.
    • Article

      Feeding regimes in relation to reproduction and survival of ablated Penaeus monodon 

      JH Primavera, C Lim & E Borlongan - Kalikasan, The Philippine Journal of Biology, 1979 - University of the Philippines at Los Baños
      Pond-reared P. monodon were stocked in four 12-cu m flowthrough maturation tanks at 25 males and 50 females per tank; females were unilaterally ablated. The combinations of feeds for the morning and afternoon rations were pellet-pellet, frozen mussel-frozen mussel, frozen mussel-pellet, and frozen squid-pellet. Reproductive performance in terms of total number of spawnings, total number of eggs produced, total number of nauplii produced, average number of eggs per spawning and average hatching rate was best for the mussel-pellet combination followed by the mussel-mussel and squid-pellet rations. The all pellet diet gave the poorest results.
    • Article

      Feeding selectivity of the seahorse, Hippocampus kuda (Bleeker), juveniles under laboratory conditions 

      FT Celino, GV Hilomen-Garcia & AGC del Norte-Campos - Aquaculture Research, 2012 - Blackwell Publishing Ltd
      This study examined the feeding selectivity of Hippocampus kuda juveniles under captive conditions and evaluates different food organisms that could be used to improve hatchery-rearing of this species. Newly born H. kuda were reared for 10 days in 60-L capacity tanks and fed rotifers (Brachionus rotundiformis), zooplankton (mostly Pseudodiaptomus annandalei and Acartia tsuensis) alone or both food sources. The size and amount of food ingested increased as seahorses grew. Selective feeding of seahorses appeared to change as they develop, preferring copepod adults over nauplii and rotifers. A. tsuensis was highly selected by juveniles over P. annandalei. Specific growth rate in terms of body weight (SGR-BW, 15% day–1) was the highest and mortality rate (9% at day 10) the lowest in seahorses fed a mixed food sources. Slowest growth rate (0.3% day–1) and highest mortality rate (60% at day 7) were observed in seahorses fed rotifers alone. These results indicate that copepods are suitable food for seahorse juveniles, but a mixture of food organisms in the rearing tank environment enhances survivorship and growth of H. kuda, thus potentially providing a source of cultured rather than wild specimens for characterizing the life history of this threatened species.
    • Article

      Feeding, growth and survival of abalone (Haliotis asinina Linnaeus 1758) reared at different stocking densities in suspended mesh cages in flow-through tanks 

      AC Fermin & SM Buen - The Philippine Scientist, 2000 - San Carlos Publications, University of San Carlos
      Feeding, growth and survival of hatchery-bred juvenile abalone, Haliotis asinina (mean initial shell lengths: 32 mm) stocked at 25, 50 and 100 m-2 of shelter surface area in mesh cages suspended in indoor tanks were determined. Animals were fed the seaweed, Gracilariopsis bailinae, to excess given at weekly intervals. After 250 d, avereage daily growth rate (mean: 122 µm d-1 shell length, 156 mg d-1 body weight) was highest in abalone reared at the lowest stocking density (25 m-2 ). Abalone stocked at 50 and 100 m-2 had similar growth rates that ranged from 96 to 98 µm d-1 SL and 123 to 131 mg d-1 BW). Daily feeding rates of 29 and 30% were not significantly different for abalone stocked at 25 and 50 m-2, respectively, but were higher than abalone stocked at 100 m-2. The higher feeding rates of 24-28% day-1 of abalone in all treatments starting day-129 until day-160 could be due to the onset of sexual maturation as most abalone are already mature at this size. Survival rates were generally high (91-98%) and were not significantly different among treatments. However, body size (range: 59.3 mm SL, 57-58.4 g BW) at harvest was bigger in animal stocked at 25 m-2 than those stocked at 100 m-2. Sexual maturation during culture did not hamper growth of abalone. G. bailinae proved to be a sufficient food source for abalone grow-out. A stocking density between 50-100 m-2 is recommended for tank grow-out of H. asinina.
    • Article

      Female-specific SNP markers provide insights into a WZ/ZZ sex determination system for mud crabs Scylla paramamosain, S. tranquebarica and S. serrata with a rapid method for genetic sex identification 

      Mud crabs, Scylla spp., are commercially important large-size marine crustaceans in the Indo-West Pacific region. As females have the higher growth rate and economic value, the production of all female stocks is extremely essential in aquaculture. However, the sex determination mechanism is still unclear. Development of sex-specific genetic markers based on next-generation sequencing proved to be an effective tool for discovering sex determination system in various animals.
    • Article

      Ferrocement bouys for mussel culture 

      RT Tolosa - Journal of Ferrocement, 1979 - International Ferrocement Information Center
      This paper describes a method of constructing 12 mm thick ferocement buoys used as a floatation system in the culture of green mussels (Mytilus smaragdinus).
    • Article

      Financial feasibility of green-water shrimp farming associated with mangrove compared to extensive shrimp culture in the Mahakam Delta, Indonesia 

      RH Bosma, EA Tendencia & SW Bunting - Asian Fisheries Science, 2012 - Asian Fisheries Society
      This paper presents a post-hoc assessment of the introduction of intensive shrimp farming strategies, with and without green-water (GW) technology, in the Mahakam Delta where extensive systems (ES) dominate. The study also assesses the potential of integrated mangrove GW shrimp production (MGW). The method section describes the systems considered, the cost-benefit analysis applied and the assumptions for different scenarios. The data for the GW and non-GW systems were based on a survey in the Philippines. Assessing cultured shrimp yields from the total farm area showed that production from non-GW was 10% higher than from GW farms. Compared to these two systems, the MGW system produces about 20% of the total shrimp, but provides complementary livelihood options and ecosystem services. Per unit area covered, MGW system produces 20 times more shrimp than ES, while income for farmers doubles and opportunities for livelihoods enhancement associated with the mangrove area increase. Low operating costs make the ES interesting for resource poor farmers, but risks to producers and societal cost are underrated. Transferring from ES to MGW system will increase the contribution to the national economy whilst maintaining ecosystem services, that would otherwise be lost, were intensive culture systems to predominate.
    • Article

      The financial feasibility of small-scale grouper aquaculture in the Philippines 

      RS Pomeroy, R Agbayani, MN Duray, J Toledo & G Quinitio - Aquaculture Economics and Management, 2004 - International Association of Aquaculture Economics and Management (IAAEM)
      This paper presents the results of an economic analysis of the aquaculture of two species of grouper E. coloides (orange‐spotted grouper, green grouper, red‐spotted grouper) and E. malabaricus (malabar grouper, black‐spotted grouper) for small producers in the Philippines. The findings of the analysis indicate that, based on the assumptions, grouper culture is financially feasible. However, the capital requirements for the broodstock, hatchery/nursery, and integrated system may be beyond the financial means of many small producers. These stages of grouper culture may need to be developed as a larger project by private investors or government. The capital investment requirement for grow‐out (not including purchase of transport boxes) is within the financial means of small producers. Loans or other incentives will need to be made available for the small producer, but the cash flow indicates that these loans can be repaid in the first year of production.
    • Article

      Fire + water + bombs: Disaster management among academic libraries in Marawi City, Lanao del Sur, Philippines 

      DL Superio, EM Abaday, MGH Oliveros, AS Delgado, VEV Palcullo & JF Geromiano - International Journal of Disaster Risk Reduction, 2019 - Elsevier
      The academic libraries in Marawi City, Lanao del Sur, Philippines are vulnerable to disasters. In the last ten years, the majority of the 13 respondent libraries have sustained at least one disaster that may have been caused by civil unrest, war or terrorism, flood, earthquake, or fire. The majority were unprepared to face such disasters, may it be small-scale or catastrophic, and only one library has a disaster management plan. The lack of significant holdings of rare books, shortage of financial resources, no perceived risk, and the unavailability of staff to write a disaster management plan, are the reasons why most libraries do not have a plan. Moreover, the majority lacked staff that has undergone training in disaster preparedness and management. On the other hand, all of the libraries have disaster management practices that although not enough, will still enable them to lessen the effects of the disaster and save their library and parts of their collection when necessary. The respondents identified management support as an essential factor in their success in disaster management. The results of the study provide valuable information on the current state of the libraries in the Philippines with regards to disaster preparedness and management. Therefore, it is an essential addition to the literature on disaster management in the Philippines, which is very scarce as of the moment.
    • Article

      The first record of a cupped oyster species Crassostrea dianbaiensis in the waters of Japan 

      M Sekino, H Ishikawa, A Fujiwara, EFC Doyola-Solis, MJH Lebata-Ramos & H Yamashita - Fisheries Science, 2015 - Springer Verlag
      With a combination of our mitochondrial and nuclear DNA data, we evidenced the occurrence of a Crassostrea oyster hitherto unrecognized in Japan. This species, C. dianbaiensis (named Sumizome-gaki in Japanese), was very recently described as a new “tropical” oyster, although we located it in a temperate water zone (southwestern coast of Shikoku Island, Japan). Our specimens bore a morphological resemblance to the slipper cupped oyster C. bilineata (syn. C. iredalei), consistent with their close phylogenetic relationship. Some of the shell characteristics represented in the original species description were not applicable to our specimens, especially in terms of the pattern of their inner-shell coloration. Our novel finding of C. dianbaiensis in Japan updated the taxon list of Japanese Crassostrea species.
    • Article

      Fish farming in marine pens and cages in the Philippines: appropriate technology? 

      TU Bagarinao - Aquaculture Engineering, 1998 - Society of Aquaculture Engineers of the Philippines, Inc.
      Contributed as Discussant in Technical Session 3 on Environmental Impacts of Marine Fishcage Farming, 12th Annual Meeting of the Society of Aquaculture Engineers of the Philippines, Inc. (SAEP), held at the BFAR-National Integrated Fisheries Technology Development Center (NIFTDC), Bonuan Binloc, Dagupan City, 07 November 1998.
    • Article

      Fish habitats in a small, human-impacted Sibunag mangrove creek (Guimaras, Philippines): a basis for mangrove resource enhancement 

      JBR Abrogueña, TU Bagarinao & L Chícharo - Ecohydrology & Hydrobiology, 2012 - Elsevier
      The fish assemblage of a small, open access mangrove creek highly influenced by aquaculture farms, was studied for the first time in the Philippines as a baseline of such system as well as examining the degree of ecological disturbance among fish habitats, as basis for the necessity to rehabilitate mangrove resources aiming to balance human activities and mangrove functioning. In total, 475 fishes (total weight = 3875 g) were captured and 50 species representing 32 families were identified. Thirty two species were represented by small numbers (< 5 individuals). Commercial species was considerably high (~23 species) but majority were low grade commercial species. Total species, species diversity and fish abundance consistently showed a decreasing pattern from outside creek to inner creek. Fish habitats exhibited substantial differences following a distinct spatial segregation of fish communities, a dominance of non-shared species and a minimal species overlapping inside the creek, which is attributable to the existing mangrove fragmentation associated with aquaculture ponds in the area. Increasing levels of disturbances were observed within the creek indicating ‘stress’ as a result of overutilization of mangroves by aquaculture farms. Our results confirmed the need to rehabilitate mangrove resources in this area. The development of mangrove resources through reforestation, coupled by strict regulation of fishing activities and aquaculture ponds will reduce ecological stress in the area and regain gradually a robust mangrove functioning that will improve fish diversity, fisheries and productivity of adjacent coastal systems by creating a suitable fish nursery, feeding ground and refuge habitat.