Now showing items 1-20 of 55

    • Article | Short communication

      Bacteria associated with infection at hormone-implantation sites among milkfish, Chanos chanos (Forsskal), adults 

      G Lio-Po, C Pitogo & C Marte - Journal of Fish Diseases, 1986 - Blackwell Publishing
      SEAFDEC Contribution No. 164. Paper presented at the Second International Warmwater Fish Conference at Laie, Hawaii, 5–8 February 1985.
    • Article

      Broodstock management and egg production of milkfish, Chanos chanos Forsskal 

      AC Emata & CL Marte - Aquaculture Research, 1993 - Blackwell Publishing
      The milkfish, Chanos chanos Forsskal, industry in the Philippines suffers from a limited supply of wild fry. The demand for milkfish fry has spurred research in artificial propagation to supplement the natural seed supply. Spontaneous maturation and spawning of milkfish beginning at 5 years of rearing in floating net cages or concrete tanks coupled with improved egg collection technique have increased daily egg collection to a maximum of 3 million eggs and provided adequate volumes of eggs for mass fry production. Annual egg collection and number of spawnings were markedly higher in cage-reared stocks older than 9 years old than stocks less than 9 years old. Egg collection of tank-reared stocks were comparable to those collected in cages. As feed constitutes a major portion of the operating expenses for establishing and maintaining milkfish broodstock, further studies must be geared towards defining optimum dietary requirements and ration size for gonadal maturation and spawning. Also environmental manipulation studies must be conducted for year-round spawning. Developments in these areas should ensure the production of maximum numbers of high quality eggs and fry year-round.
    • Conference paper

      Broodstock management and seed production of milkfish 

      CL Marte - In JV Juario & LV Benitez (Eds.), Seminar on Aquaculture Development in Southeast Asia, 8-12 September 1987, Iloilo City, Philippines, 1988 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Milkfish (Chanos chanos Forsskal) remains one of the cheapest sources of protein for developing countries in Southeast Asia, particularly in the Philippines. The unpredictable supply of wild fry, the only source of seed for the milkfish farmer, contributed largely to the slow growth of the milkfish industry. Research on the artificial propagation of this fish was, therefore, given emphasis.

      Major research achievements in milkfish breeding of the SEAFDEC Aquaculture Department in the last decade include: (1) successful induced spawning of wild and captive breeders using gonadotropin preparations and gonadotropin-releasing hormone analogues (GnRHa); (2) spontaneous maturation and spawning of captive breeders; (3) completion of the life cycle of milkfish in captivity; (4) development of a simple egg-collecting method; and (5) development of techniques for mass production of milkfish fry.

      Information on fry ecology and behavior, larval morphology and physiology were also gathered. These published data constitute the bulk of current knowledge on milkfish biology and natural history.

      Milkfish breeding technology is currently being pilot-tested in several breeding sites of the Bureau of Fisheries and Aquatic Resources (BFAR). Spontaneous maturation and spawning of milkfish have been verified in four sites which differ in environmental characteristics. The economic feasibility of producing milkfish fry and the socio-economic impact of artificial propagation of milkfish are now being assessed.
    • Conference paper

      Changes in lipid and fatty acid content during early larval development of milkfish (Chanos chanos): influence of broodstock diet 

      CL Marte, IG Borlongan & AC Emata - In CL Marte, GF Quinitio & AC Emata (Eds.), Proceedings of the Seminar-Workshop on Breeding and Seed Production of Cultured Finfishes in the Philippines, Tigbauan, Iloilo, Philippines, 4-5 May 1993, 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The influence of amount and type of lipid given to milkfish broodstock by developing larvae was investigated by feeding broodstock commercial diets that differed in lipid content and composition. The two commercial feeds used had the following proximate composition: RFP - 28.16% crude protein, 2.40% crude fat, 7.58% crude fiber, 53.94% N-free extract; RCP - 43.28% crude protein, 4.58% crude fat, 6.18% crude fiber, 37.0% N-free extract.

      The lipid content and fatty acid composition of spawned milkfish eggs reflected that of the broodstock feed. Percent lipid in egg from broodstock fed RFP and RCP dropped by 22.5% and 26.9% in newly-hatched larvae and by 53.0% and 65.0% in day 2 larvae (>90% yolk resorbed), respectively. Decreases in total PUFA and increase in monoenoic fatty acids during yolk resorption indicate that milkfish as in other marine fishes utilize PUFA during early larval development. While differences in rate of utilization of individual n-3 and n-6 FA in two groups of larvae seem to be influenced by levels of the fatty acids in eggs, the influence of other nutrients on fatty acid utilization need to be investigated.
    • Article

      A collecting gear for naturally-spawned milkfish (Chanos chanos Forsskal) eggs in circular floating net cages 

      LMB Garcia, CL Marte & VS Travina - Aquaculture, 1988 - Elsevier
      A collecting gear for naturally-spawned milkfish (Chanos chanos Forsskal) eggs in circular floating net cages is described. The gear has been shown to be effective in collecting large numbers of eggs. The collecting gear can be adopted for other broodstock fish species held in circular floating net cages.
    • Conference paper

      Collection of naturally-spawned milkfish eggs in floating cages 

      CL Marte, J Toledo, G Quinitio & A Castillo - In JL Maclean, LB Dizon & LV Hosillos (Eds.), The First Asian Fisheries Forum. Proceedings of the First Asian Fisheries Forum, 26-31 May 1986, Manila, Philippines, 1986 - Asian Fisheries Society
      Natural spawnings of milkfish from floating cages were obtained from different stocks of 5-7 year-old milkfish in 1980, 1981, 1983 and 1985. The maximum number of eggs collected in 1980, using a series of 1-m diameter stationary plankton nets, was about 900. Increased collections were obtained in succeeding years with different types of egg collectors and methods. Egg collection, however, is inferior when based on the expected number of eggs spawned by a single female. Although no systematic study was attempted to compare efficiency of various egg-collecting gears and methods, the problems associated with the use of each gear are presented. The experience may be used as a guide in future designs of efficient gears of collecting naturally-spawned eggs of milkfish or other fish species in floating cages.
    • Article

      Controlled release of testosterone and estradiol-17 β from biodegradable cylinders 

      X Zhang, UP Wyss, D Pichora, MFA Goosen, A Gonzal & CL Marte - Journal of Controlled Release, 1994 - Controlled Release Society
      A controlled release device for the hormones, testosterone and estradiol-17 β, was developed by coating a melt extruded hormone/poly (ϵ-caprolactone) cylinder with pure polylactide. Since testosterone and estradiol-17β have much higher permeabilities in poly (ϵ-caprolactone) than in polylactide, they primarily permeate through the open ends of the cylinder, with little release through the polylactide wall. By changing the cylinder length, the release rate and duration could be adjusted. The release followed Pick's diffusion equation for a drug loading below its solubility in poly (ϵ-caprolactone) or Higuchi's equation for a drug loading above the solubility. The diffusion coefficients of testosterone and estradiol-17β in poly (ϵ-caprolactone) were estimated as (8.31 ±3.12) × 10−18 and (0.728 ± 0.250) × 10−18 cm2/s, respectively.
    • Article

      The coral communities of Mararison Island, Culasi, Antique, Philippines 

      CL Marte & YP Tirol - UPV Journal of Natural Sciences, 2006 - University of the Philippines in the Visayas
      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 as part of the Community Fisheries Resource Management project launched in 1991. The fringing reefs on the northwest side of the island are characterized by high percent coral cover (53-65%) consisting of very diverse coral species. The dominant forms are branching non-Acropora,with numerous small colonies of other coral forms. In contrast, the southeast side of the island fronting the fishing village is depau perate (4.7 -17.6% coral cover) with few small colonies of encrusting and massive corals characteristic of stressed reefs. However, highest coral cover consisting of dense stands of branching Acropora interspersed with branching non-Acropora was observed along the reef slope of Nablag station located at the western end of the island. Coral cover in the offshore reef (Guiob) was relatively fair (24%-46%). A total of 166 scleractinian corals were seen although only few species occurred frequently or provided high percent coral cover. Following the bleaching event of 1998, dramatic decreases (30%-61%) in live coral cover, particularly along the reef slopes, were observed in all stations.
    • Coral reefs 

      CL Marte - In Training Handbook on Rural Aquaculture, 2009 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • Conference paper

      Development of artificial diets for milkfish (Chanos chanos) larvae 

      I Borlongan, C Marte & J Nocillado - 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      This study aims to develop nutritionally balanced and cost-effective artificial diets for milkfish larvae. Two larval diets (Feed A and Feed B) were formulated and prepared to contain 45% protein and 10% lipid. Several larval diet preparation techniques were tried and diets produced were assessed in terms of feed particle size and bouyancy, water stability, and feed acceptability. The larval diet preparation that gave the best particle size and bouyancy as well as good water stability was the one prepared as microbound diet (using K-carrageenan as a binder) and flaked using a drum drier.A series of feeding experiments were then conducted to determine growth and survival of milkfish larvae reared on various feeding schemes involving the use of these artificial diets. The artificial diets were fed either alone or in combination with live foods. Larvae in control treatments were reared on live foods such as Brachionus and Artemia. Larvae were observed to ingest the diets indicating that the feeds had suitable physical characteristics and were attractive to the larvae. Over-all results of the feeding trials showed that the artificial diets could be fed to milkfish larvae in combination with the rotifer Brachionus starting Day 8 or could be fed alone to milkfish larvae starting Day 15 onward. These promising results would reduce dependence of milkfish larvae on live foods and would have significant economic benefits in the form of simplified milkfish hatchery procedures.
    • Article

      Development of larval diets for milkfish (Chanos chanos) 

      IG Borlongan, CL Marte & JN Nocillado - Journal of Applied Ichthyology, 2000 - Blackwell Publishing
      This study aimed to develop nutritionally balanced and costeffective processed diets for milkfish larvae (Chanos chanos). Two larval diets (feed A and feed B) were formulated and prepared to contain 45% protein and 10% lipid. Several larval diet preparations were tried such as microbound/unpelleted (freeze-dried), microbound /pelleted (oven-dried) and microbound/flaked (drum-dried) and assessed in terms of feed particle size and buoyancy, water stability and feed acceptability. The preparation that gave the best particle size and buoyancy as well as good water stability was prepared as the microbound diet (using K-carrageenan as a binder) and flaked using a drum drier. A series of feeding experiments were conducted to determine the growth and survival of milkfish larvae reared on various feeding schemes using these processed larval diets which were fed either solely or in combination with live feed. Larvae in control treatments were reared on live foods such as Brachionus plicatilis and Artemia nauplii. Larvae were observed to ingest the diets, indicating that the feeds had suitable physical characteristics and were attractive to the larvae. The overall results of the feeding trials showed that the artificial diets could be fed to milkfish larvae in combination with Brachionus rotifers starting on day 2 or day 8, and could be fed alone starting from day 15. These promising results would reduce the dependence of milkfish larvae on live feed and would have significant economic benefits in the form of simplified milkfish hatchery procedures.
    • Article

      Economic assessment of commercial hatchery production of milkfish (Chanos chanos Forsskal) fry 

      LMB Garcia, RF Agbayani, MN Duray, GV Hilomen-Garcia, AC Emata & CL Marte - Journal of Applied Ichthyology, 1999 - John Wiley and Sons
      The economic viabilities of two types of commercial hatchery milkfish (Chanos chanos) fry operations were assessed and compared. Based on the actual cost of input, the physical facilities, and the potential production yields, four commercial hatcheries previously used for shrimp (Penaeus monodon fry production were classified as either largeor smallscale operations. Cost-return analysis revealed high profits for both types of operation. The return on investment (54-61 %) and the payback period ( approximately 1.5 years) were comparable between the two types, although a large-scale operation (476 %) had double the working capital return of a small-scale hatchery (221 %). Benefit-cost analysis over a 5-year period also revealed positive and above-baseline discounted economic indicators [net current value = 0.2-2.2 million Philippine Pesos (1 US Dollar = 25 Philippine Pesos); internal rate of return = 88-107 %]. The net benefit-cost ratio of a large-scale operation (2.0) was higher than that of a small-scale hatchery (1.4), suggesting a slight edge in the investment viability of a large-scale hatchery. Compared with a large-scale operation, a small-scale hatchery was more sensitive to changes in the acquisition price of eggs or newly-hatched larvae and in the price of selling hatchery fry. Both types of operation are viable nonetheless when the acquisition cost is P6000 per million eggs or larvae and hatchery fry are sold at P0.50 each. Together, profit and investment in milkfish hatchery fry production appear viable, making milkfish an alternative commodity for production in many abandoned shrimp hatcheries. The limited availability of spawned eggs and larvae for rearing and the quality of hatchery fry are issues requiring urgent attention.
    • Article

      Effect of season on oocyte development and serum steroid hormones in LHRHa and pimozide-injected catfish Clarias macrocephalus (Günther) 

      JD Tan-Fermin, CL Marte, H Ueda, S Adachi & K Yamauchi - Fisheries Science, 1999 - Japanese Society of Fisheries Science
      Oocyte and blood samples were taken from gravid female catfish Clarias macrocephalus at 4-h intervals to monitor the stage of oocyte development and serum steroid hormone profiles after injection of luteinizing hormone-releasing hormone analogue (LHRHa) and pimozide (PIM) during the off-season (February) and the peak of the natural breeding period (August). Results showed that the onset of final oocyte maturation (12h) and ovulation (16h), and levels of serum estradiol-17β (E2) did not vary with season in LHRHa+PIM-injected fish. In February, ovulated eggs were stripped from three and two hormone-treated fish at 16h and 20h post-injection, respectively. In August, ovulation was observed in all hormone-treated females (n=5) at 16h post-injection but stripping of the eggs was possible only 4h thereafter. Serum E2 levels were significantly different only with varying time post-injection; a marked increase occurred at 12h, but the elevation was higher in fish induced to ovulate during the peak (16.8ng/ml) than off-season (7.7ng/ml). Hormone-treated fish showed higher serum testosterone (T) levels during the peak season (17-23ng/ml) than those injected during the off-season (10-20ng/ml) at 4-12h post-injection. Serum 17α, 20β-dihydroxy-4-pregnene-3-one (DHP) levels of hormone-treated fish during the off-season were only about half the level (0.29 and 0.52 ng/ml) of those treated with the same hormones during the peak season (0.54 and 0.9ng/ml) at 8 and 12h postinjection, respectively. Development of oocytes and serum steroid hormone profiles after LHRHa+PIM-induced ovulation provide basic understanding of the processes that mediate final oocyte maturation and ovulation in captive C. macrocephalus.
    • Book

      Fingerling production of hatchery-reared milkfish (Chanos chanos) in earthen nursery ponds 

      EB Coniza, CL Marte, RM Coloso & FL Huervana - 2010 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Series: Aquaculture extension manual no. 45
      Fingerling production of milkfish in ponds maybe operated as a commercial enterprise or a component of milkfish farming that comprises nursery, transition and rearing or grow-out phases. The fishpond nursery is used to grow milkfish fry to fingerlings 1-3 g in weight or 1-2 inches in length. The nursery pond is the smallest of the major fishpond compartment ranging from 500 to 5,000 m2, and is about 10% of the total farming area. The pond is prepared with utmost care to eliminate predators and competitors. The area should have good topography, is free from flooding and should have soil with good water retention properties for good dike construction and efficient culture management. Water supply should be adequate year-round and free from pollutants. Good pond water quality is maintained and natural food should be adequate to enhance growth and survival. With high stocking densities, supplemental feed is also provided. The three types of nurseries are based on feed sources: lablab, plankton with supplemental feeding and direct feeding. Select hatchery-reared fry (21 day old) that swim actively in schools, are uniform in size, have robust body, and are resistant to handling and transport stress. The ideal fry stocking density is 5-40 pieces/m2. Survival ranging from 50-90% can be expected after 25-45 days of rearing. Harvest, packing, transport, acclimation and stocking of the fry or fingerlings are carefully done during the cooler part of the day. Economic indicators show that fingerlings production is a profitable business. The improvement of milkfish grow-out technology from extensive or traditional to modified-extensive, semi-intensive and intensive culture in ponds, pens or in sea cages has increased demand for good quality fingerlings. Mass production of hatchery-reared fingerlings in earthen nursery ponds during peak season of fry availability can help bridge the supply gap. A steady supply of fingerlings for a whole year s operation will further increase production and ensure a sustainable supply of affordable market-sized fish.
    • Conference paper

      Fisheries 

      EEC Flores & CL Marte - In S Manarungsan, EEC Flores, CL Marte & K Igusa (Eds.), The Possibilities of Technical Cooperation Between Southeast Asia and Okinawa Prefecture in Japan, 1996 - Institute of Developing Economies
    • Article

      The food and feeding habit of Penaeus monodon Fabricius collected from Makato River, Aklan, Philippines 

      CL Marte - SEAFDEC Aquaculture Department Quarterly Research Report, 1978 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The food of Penaeus monodon collected from Makato R., from Sept 1977 to Jan 1978 is described with preliminary observations on its feeding habit and rate of foregut clearance. Feeding behaviour appears to be associated with the tidal phase. Foregut clearance rate is rapid, with 95% of food transported from the foregut 4 h after feeding. Frequency of occurrence and proportion of total food of various foregut contents are shown, as are dry weight, percentage mineral, organic and crude protein nitrogen from individual and pooled samples of gut contents, and foregut index in P. monodon collected during different phases of one tidal cycle.
    • Article

      The food and feeding habit of Penaeus monodon Fabricius collected from Makato River, Aklan, Philippines (Decapoda: Natantia) 

      CL Marte - Crustaceana, 1980 - E.J. Brill
      The food of Penaeus monodon Fabricius collected from Makato River, Aklan, consisted mainly of Crustacea (small crabs and shrimps) and molluscs, making up 85% of ingested food. The remaining 15% consisted of fish, polychaetes, ophiuroids, debris, sand, and silt. Results indicate that P. monodon is more of a predator of slow-moving benthic macroinvertebrates rather than a scavenger or detritus feeder. Feeding activity (determined from stomach fullness) of female prawns is significantly higher than that of males. Preliminary experiments on foregut clearance revealed that clearance rate is rapid with 95% of food transported from the foregut 4 hours after feeding. Feeding behavior of P. monodon appears to be associated with the tidal phase. A significantly higher mean gut fullness index indicative of increased feeding activity, was noted when the tide is on the ebb.
    • Article

      Gonadotropin profiles in serum of milkfish treated with salmon pituitary homogenate 

      CL Marte & LW Crim - Kalikasan, The Journal of Philippine Biology, 1983 - University of the Philippines Los Baños
      Serum gonadotropin (GtH) levels were determined by radioimmunoassay (RIA) in adult regressed milkfish injected or implanted with various doses of salmon pituitary homogenate (SPH). Gonadotropin profiles of injected or implanted milkfish show similar trends. Elevation of serum GtH occurred a day after treatment in all groups irrespective of the administered dose. The level dropped after 2 or 3 days and in the implanted fish, was at the initial level 10 days after treatment. The expected slow and sustained release of hormone from the SPH pellet was not obtained even at the high dose given.

      A preliminary investigation of the milkfish pituitary homogenate using the salmon-GtH-RIA system shows no cross reaction of milkfish GtH with salmon GtH antibody, indicating that the milkfish and salmon gonadotropins are immunologically distinct molecules.
    • Conference paper

      Grouper research at the Southeast Asian Fisheries Development Center Aquaculture Department 

      CL Marte - In Asia-Pacific Economic Cooperation & Network of Aquaculture Centres in Asia-Pacific (Eds.), Report of the APEC/NACA Cooperative Grouper Aquaculture Workshop, Hat Yai, Thailand 7-9 April 1999, 2002 - Network of Aquaculture Centres in Asia-Pacific
      This paper provides information on grouper research activities that have been carried out in SEAFDEC AQD. It covers various aspects such as broodstock management, seed production, nursery and grow-out culture techniques.
    • Conference paper

      Growth and survival of milkfish (Chanos chanos) larvae reared on artificial diets 

      IG Borlongan, CL Marte & J Nocillado - In CL Marte, GF Quinitio & AC Emata (Eds.), Proceedings of the Seminar-Workshop on Breeding and Seed Production of Cultured Finfishes in the Philippines, Tigbauan, Iloilo, Philippines, 4-5 May 1993, 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      A preliminary feeding experiment was conducted to determine growth and survival of milkfish larvae reared on various feeding regimes involving the use of artificial diets. Two larval diets (Feed A and Feed B) containing 45% protein and 10% lipid were fed either alone or in combination with Brachionus from day 8 to day 21. The feed in the control treatment were Brachionus (10 ind/ml) from day 8 to day 14 and Artemia (2-3 ind/ml) from day 15 to day 21. Larvae in all treatments were fed Brachionus (10 ind/ml) from day 2 to day 7.

      No significant differences were observed in survival rates, total length, wet weight and dry weight among fish fed combination of Brachionus and Feed B and the control feed (Brachionus and Artemia). These promising results indicate the possibility of using Feed B as partial replacement or supplement to live food. However, lowest survival rates, total length, and weight were obtained in fish fed either Feed A or Feed B alone, indicating that the test artificial diets given solely to milkfish larvae starting from day 8 can not support good growth and survival. Further studies on the development of improved artificial diets for larval milkfish need to be done.