Now showing items 1734-1753 of 3350

    • Article

      L-ascorbyl-2-phosphate Mg as source of vitamin C for juvenile Penaeus monodon 

      MR Catacutan & CR Lavilla-Pitogo - The Israeli Journal of Aquaculture-Bamidgeh, 1994 - Society of Israeli Aquaculture and Marine Biotechnology
      Phosphated ascorbic acid (MAP), a stable vitamin C derivative, was used in practical diets for Penaeus monodon (wet weight, 126-254 mg) as a source of vitamin C. In Experiment I, the levels were from 0 to 1,500 ppm MAP. No significant differences in weight gain, SGR, survival and FCR were observed among treatment means after 92 days of feeding but the lowest values were obtained in the group fed without the MAP dietary supplement. At the start of the experiment shrimps were infected with monodon baculovirus (MBV). However, the histological structure of the hepatopancreas showed improvement in animals fed diets containing 100 ppm MAP and above, after 92 days.

      In Experiment II, shrimps were given different MAP levels (0 to 8,000 ppm) for 81 days. The FCR and survival of shrimps in MAP supplemented diets were significantly higher than those without MAP. In both experiments, shrimps without dietary MAP were weak and developed blackened subcuticular tissues, a symptom of vitamin C deficiency. MAP was utilized by P. monodon as a source of vitamin C. An adequate level in a practical diet would be 100 to 200 ppm MAP, equivalent to 50 to 100 ppm ascorbic acid.
    • Conference paper

      L-ascorbyl-2-phosphate Mg as vitamin C source for juvenile Penaeus monodon 

      M Catacutan & C Lavilla-Pitogo - 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Phosphated ascorbic acid (magnesium L-ascorbyl-2-phosphate or MAP) is a stable form of vitamin C. The suitability and growth requirement level of this derivative in practical diet was determined for juvenile Penaeus monodon. The stability and shelf-life of this derivative was compared with that of crystalline ascorbic acid in prepared shrimp diets. Leaching test was conducted at time intervals of 0 to 6 hours while storage test was conducted for 2 weeks to 3 months.In Experiment I, shrimps (183-254 mg) were given MAP at 0 to 1,500 mg/kg diet for 92 days. Shrimps given the diet without MAP supplement had the lowest growth, survival and feed conversion efficiency, but these were not significantly different from those of shrimps fed diets containing different MAP levels. The shrimps were infected with monodon baculovirus at the start of the experiment. At termination, the histological structure of the hepatopancreas showed improvement in those fed diets containing MAP at 100 mg/kg diet or higher.In Experiment II, shrimps (126-135 mg) were fed with diets containing MAP at 0-8,000 mg/kg diet. Seaweed was removed from the diet composition. After 81 days, shrimps given diet without MAP had significantly lower survival rate and feed conversion efficiency than the shrimps fed diets with MAP. Growth was lowest in shrimps without MAP but was not significantly different from that of shrimps given MAP. After feeding for 81 days on diets with different MAP levels, the shrimps were wounded and further maintained with their respective dietary treatments to observe the effects of MAP in wound healing. Complete healing of wounds were observed after two weeks among shrimps given with MAP at 100 and 200 mg/kg diet. In both experiments, shrimps without dietary MAP were weak and showed symptoms of vitamin C deficiency. Higher levels of MAP did not result in very high mortalities in shrimps. This study showed that MAP was utilized by P. monodon as a vitamin C source and the adequate level would be about 100 to 200 mg/kg of diet or 50 to 100 mg as ascorbic acid per kg diet.
    • Article

      Laboratory breeding of the mud crab Scylla serrata (Forskal) through the zoea and megalopa stages to the crab stage 

      H Motoh, D de la Peña & E Tampos - SEAFDEC Aquaculture Department Quarterly Research Report, 1977 - Aquaculture Department, Southeast Asian Fisheries Development Center
      A series of experiments is being conducted to establish breeding techniques to mass-produce seedlings of S. serrata for pond cultivation to meet the commercial demand for the crab. The objective is to culture the crab through the 5 zoea stages and 1 megalopa stage to the crab stage. A brief resume of the experiments is presented. Heavy mortality occurred at the 1st, 2nd and 5th zoea stages, and during the megalopa stage. Initial mortality is attributed to unfavourable rearing conditions, and later mortality to cannibalism.
    • Article

      Laboratory manipulation of Gracilariopsis bailinae Zhang et Xia (Gracilariales, Rhodophyta) 

      SF Rabanal, R Azanza & A Hurtado-Ponce - Botanica Marina, 1997 - Walter de Gruyter
      Carpospore germination, carposporeling development and tetraspore formation were investigated in Gracilariopsis bailinae Zhang et Xia by manipulating photoperiod, photon flux density, temperature, salinity and nutrients. Laboratory-generated sporelings attained mean growth rate from 4.05 to 10.31% d-1 during the first week of incubation. Duncan s multiple range test (DMRT) showed that growth rates were significantly different (P < 0.05) between the treatment combinations and between weekly intervals. The optimal condition for growth of sporelings, irrespective of culture age, was attained at treatment combinations of 26°C, 11:13 (h. L:D) photoperiod, 100 µEm-2s-1 photon flux density (PFD), 25 µM NH4Cl: 2.5 µM K2HPO4 and 25ppt salinity followed by a treatment combination of 26°C, 11:13 (h. L:D) photoperiod, 100 µEm-2s-1 photon flux density (PFD), 50 µM NH4Cl: 5 µM K2HPO4 and 25 ppt salinity. For the first time in this species, tetraspore formation was induced in the laboratory. The tetrasporophyte produced many tetraspores in almost all branches of the thallus grown at 26°C, 11:13 (h. L:D) photoperiod, 100 µEm-2 s-1, 25 µM NH4Cl: 2.5 µM K2HPO4 and at 30 ppt salinity while those grown at lower light, higher nutrient level and higher salinity had fewer tetraspores. No tetraspores were formed at a higher temperature (30°C), longer photoperiod (13:11 h. L:D), and at 25 ppt salinity and the plants remained vegetative from 4 to 7 months. Logistic regression analysis showed that tetrasporangial induction was significantly affected by nutrients and salinity (P < 0.05).
    • Book

      Laboratory manual of standardized methods for antimicrobial sensitivity tests for bacteria isolated from aquatic animals and environment 

      L Ruangpan & EA Tendencia - 2004 - Aquaculture Department, Southeast Asian Fisheries Development Center.
      The manual is one of the important outputs of a collection of studies related to antibiotic usage in order to come up with guidelines for its prudent usage. It offers a complete guide for testing bacterial susceptibility and resistance through the use of simple techniques for disk agar diffusion tests, and a guide to do a more thorough study to test therapeutic levels using microbial inhibitory concentration.
    • Book

      Laboratory manual of standardized methods for the analysis of pesticide and antibiotic residue in aquaculture products 

      IG Borlongan & JNP Chuan - 2004 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The manual contains guidelines on the detection of antibiotic and pesticide residues in aquaculture products. Different methods for the analysis of the two chemicals are discussed. The manual is expected to benefit all those who are involved in the monitoring and enforcement aspects of chemical residue limits in aquaculture products in the region.
    • Article

      Lactate dehydrogenase isozyme patterns during the development of milkfish, (Chanos chanos (Forskal)) 

      PD Requintina, LM Engle & LV Benitez - Kalikasan, The Philippine Journal of Biology, 1981 - University of the Philippines at Los Baños
      Polyacrylamide disc gel electrophoresis was done to determine the lactate dehydrogenase (LDH) isozyme patterns for fry (5-3 mg), fingerling (6-12 g), pond-size (150-250 g) and adult (6-9 kg) milkfish. The patterns were tissue specific; the different tissues examined, viz., eye, liver, heart, and skeletal muscle had different expressions of LDH isozymes. The resolved patterns appeared to be products of LDH gene loci A, B, and C. Subunits A and B were present in all tissues. A4 and B4 were predominant in skeletal and heart muscle, respectively; the two associated non-randomly in vivo and formed only the heteropolymers A3B and AB3. A liver band, L4, was most conspicuous in the fingerling, pond-size, and adult; it was assumed to be coded by locus C. A negatively charged band, X4, was detected in fully developed ovary and in fry homogenized as whole individuals, but it could not be resolved in tissues of fingerling.

      Six-mo old stunts and 3-mo old fingerlings had similar LDH patterns for all tissues examined. The patterns for 11-mo old stunts and fingerlings also were similar but the one for the eye of the former was the same pattern resolved for the eye of adults.

      There was no change in the LDH isozyme patterns of milk fish stunted for 6 mo under different salinity levels (0-5, 15-20, 32-35 ppt).
    • magazineArticle

      Laguna de Bay and LLDA 

      AS Frio - SEAFDEC Asian Aquaculture, 1999 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • Conference paper

      Lake Lanao: Its past and present status 

      RP Rosagaron - In Conservation and Ecological Management of Philippine Lakes in Relation to Fisheries and Aquaculture: Proceedings … Seminar-Workshop held on October 21-23, 1997, INNOTECH, Commonwealth Ave., Diliman, Quezon City, Philippines, 2001 - Aquaculture Department, Southeast Asian Fisheries Development Center; Philippine Council for Aquatic and Marine Research and Development (PCAMRD), Department of Science and Technology; Bureau of Fisheries and Aquatic Resources
      Geographically located in Central Mindanao, Lake Lanao is the second largest lake in the Philippines. The lake is famous locally for its various uses and internationally for its endemic cyprinids. This paper intends to inform the local leaders and the national planners about Lake Lanao's dwindling fisheries resources, the extinction of some endemic cyprinids, and the current interventions as well as suggested action plans to increase fish production and to conserve the remaining species in the lake. The past and present studies on the lake are also reviewed. Early and latest statistics on the lake's fisheries production are presented to invite the interest of all sectors in coming up with the integrated approach to protect, conserve and increase its fisheries production. Local and national interventions to conserve and increase fisheries production are discussed. These include the setting up of BFAR Fisheries Station in Kialdan, Marantao; the establishment of a fish hatchery in Poona, Marantao by Southern Philippines Development Authority; the formation of Save Lake Lanao Movement by the local leaders; the creation of Lake Lanao Research and Development Council; the current concern of Philippine Council for Aquatic and Marine Research and Development-DOST; and the extension and research and development thrusts of the Mindanao State University, College of Fisheries in Marawi City.
    • Article

      The lancelets [Cephalochordata, Amphioxi] of Lucena Anchorage, Quezon, Philippines 

      NC Carandang - Kalikasan: The Philippine Journal of Biology, 1978 - University of the Philippines at Los Baños
      Two species of lancelets (amphioxi) are described from Philippine waters: Branchiostoma belcheri and Epigonichthys cultellus. The characters suited for numerical evaluation in both species were examined statistically.

      Epigonichthys cultellus is reported for the first time from the Philippines. The specimens examined differ by the presence of a dark band behind the rostrum and anterior to the first myotome, the greater number of myotomes in the preatrioporal region, and the numerous sense papillae on the buccal cirri.
    • Article

      Land-based mass production of prawn (Penaeus monodon Fabricius) spawners 

      JH Primavera - SEAFDEC Aquaculture Department Quarterly Research Report, 1977 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The first spawnings were obtained 12 days after ablation with 4 spawners yielding 784,000 eggs and a harvest of 250,000 P10 fry. Survival of females after 1 month was approximately 30%. Mortalities were mostly due to handling stress during the regular ovarian samplings as well as disease from the accumulated excess feeds on the bottom of the tank. Male survival could not be recorded because of transfers to other tanks and addition of new stocks. Development seemed to peak 3 weeks after ablation. The average number of eggs per ablated spawner was 120,000. However, many of the partially spawned females were removed from the spawning tanks the following day so that remaining eggs released in the next 2 to 3 days could not be recorded. Estimate of the average number of eggs per ablated spawner is 120,000-150,000 in contrast to 500,000 per wild spawner. However, the low production cost more than compensates for the difference. Fry reared in the Wet Laboratory were used for experiments, mostly on feeding. Therefore, survival at harvest is not to be taken as a reflection of stock quality. Although fewer in number, larvae from ablated prawns are as healthy in terms of vigor in swimming and feeding as those from wild females. Most mortalities are due to inability to molt caused by lower water temperatures and inadequate feeding.
    • Conference paper

      Lao PDR: developments in aquaculture after the 2001 ASEAN-SEAFDEC fisheries millennium conference. 

      K Roger - In BO Acosta, RM Coloso, EGT de Jesus-Ayson & JD Toledo (Eds.), Sustainable aquaculture development for food security in Southeast Asia towards 2020. Proceedings of the Regional Technical Consultation on Sustainable Aquaculture Development in Southeast Asia Towards 2020, 2011 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • Article

      Large scale hatchery production of Penaeus monodon using natural food and artificial diets 

      MN Bautista, F Parado-Estepa, OM Millamena & EL Borlongan - The Israeli Journal of Aquaculture-Bamidgeh, 1991 - Society of Israeli Aquaculture and Marine Biotechnology
      Natural food in combination with either SEAFDEC formulated or other commercial larvae diets was tested for large scale production of Penaeus monodon postlarvae. Two trials of 3 treatments each, 2 replications of each treatment, were conducted in 10 m3 circular concrete tanks. Shrimps were reared from nauplii to postlarvae. Dietary treatments for trial I included:(a) natural food (NF) alone, (b) NF+ commercial plankton substitute (PS) and (c) NF+ SEAFDEC diet (SD).For trial II, commercial powder diets SP or SMP were added:(a) NF + SP, (b) NF + PS + SP + SMP and (c) NF + SD + SP + SMP. Larvae survival was significantly higher in treatments containing the SEAFDEC diets than in the treatments receiving natural food alone (trial I) or natural food in combination with SP (trial II). Larval development was faster in the group fed the SEAFDEC diet; larvae in these groups metamorphosed into postlarvae an average of 1-2 days earlier than groups fed other diets. The presence of either SP or SMP did not improve the efficiency of the feeds. Results showed that larvae performance was affected by the nutrient composition of the diets and that by using proper feeding techniques and management of water quality, large scale hatchery production of P. monodon using natural food in combination with the SEAFDEC diet or plankton substitute is possible.
    • Article

      Larvae and juveniles of pempheridid fishes, Pempheris xanthoptera and P. japonica 

      H Kohno - Japanese Journal of Ichthyology, 1986 - The Ichthyological Society of Japan
      Larval developments of Pempheris xanthoptera and P. japonica were described on 31 (6.45–22.40 mm SL) and 5 (10.35–35.70 mm SL) specimens, respectively, with particular attention to cartilaginous development. Comparison between the two species indicated that P. xanthoptera was discriminated from P. japonica by the following key characters: two supracleithral spines (one in P. japonica); longer pectoral fin; shorter ventral fin; and absence of melanophore on mid-ventral part of lower jaw and anterolateral region of trunk, and web of ventral fin.
    • Article

      Larvae of decapod crustacea of the Philippines - I. The zoeal stages of a swimming crab, Charybdis cruciata (Herbst) reared in the laboratory 

      H Motoh & AC Villaluz - Nippon Suisan Gakkai Shi. Bulletin Of The Japanese Society Of Scientific Fisheries, 1976 - The Japanese Society of Scientific Fisheries
      Six zoeal stages of Charybdis cruciata (Herbst) which are reared in the laboratory, are described. The zoea has a rostral, a dorsal and a pair of laterial spines. There are a pair of lateral hooks on the 2nd and 3rd abdominal segments. The number of natatory hairs on the rirst and second maxillipeds increased by one pair at each molt, being 4, 6, 8, 10, 12 and 14, in the 1st to 6th zoea, respectively. The number of inner setae on the telson are 3+3 in stage 1; 4+4 in stages 2 and 3, 4+1+4 in stage 4, and 5+5 in stages 5 and 6. Spinal arrangement form proximal to distal segment of the endopodite of the first maxillipeds are 2-2-0-2-5 in stages 1-3 and 2-2-1-2-6 in stages 4-6 and that of the second maxillipeds are 1-1-4 in stages 1 and 2 and 1-1-5 in stages 3-6.
    • Article

      Larvae of decapod crustacea of the Philippines. III. Larval development of the giant tiger prawn, Penaeus monodon reared in the laboratory 

      H Motoh - Nippon Suisan Gakkai Shi. Bulletin Of The Japanese Society Of Scientific Fisheries, 1979 - The Japanese Society of Scientific Fisheries
      The egg, larval stages and the first postlarva of the giant tiger prawn, Penaeus monodon Fabricius, reared from egg in the laboratory are described and illustrated.

      Six naupliar, three protozoeal and three mysis stages are recognized. The larvae of P. monodon are morphologically similar to those of P. japonicus described by Hudinaga except for the following characters: 1) number of setae on first antenna of fourth and fifth nauplii is 5 or 6 in P. monodon, but it is 7 in P. japonicus; 2) supra-orbital spine of second protozoea is bifurcated at base in P. monodon, but at tip in P. japonicus; 3) number of segments of endopod of second maxilliped of second mysis is 5 in P. monodon, but it is 4 in P. japonicus; 4) number of rostral spines in second and third myses is 0 and 0 or 1 respectively in P. monodon, but it is 1 and 2 respectively in P. japonicus.
    • Article

      Larvae of decapod crustacea of the Philippines. IV. Larval development of the banana prawn, Penaeus merguiensis reared in the laboratory. 

      H Motoh & P Buri - Nippon Suisan Gakkai Shi. Bulletin Of The Japanese Society Of Scientific Fisheries, 1979 - The Japanese Society of Scientific Fisheries
      The eggs, the larval stages and the first postlarva of the banana prawn, Penaeus merguiensis, from Philippine waters are described and illustrated.

      The complete larval stage consisting of six naupliar, three protozoeal and three mysis sub-stages were reared from egg spawned in the laboratory. The larval and postlarval stages of the present materials are compared with those of P. merguiensis from India, P. monodon from the Philippines and P. japonicus from Japan. The morphological characteristics of P. merguiensis are identical with those of genus Penaeus in Gulf of Mexico, except for the absence of the dorso-median spine on the third abdominal segment in the mysis stage of. P. merguiensis.
    • Article

      Larval and early juvenile development of silver therapon, Leiopotherapon plumbeus (Actinopterygii: Perciformes: Terapontidae), reared in mesocosms 

      FA Aya, MNC Corpuz, MA Laron & LMB Garcia - Acta Ichthyologica et Piscatoria, 2017 - Szczecińskie Towarzystwo Naukowe
      The silver therapon, Leiopotherapon plumbeus (Kner, 1864), is an endemic and economically important freshwater food fish in the Philippines. The natural populations of this species have been declining during the past years, mainly due to intense fishing pressure, habitat degradation, and introduction of invasive alien species. At present, it is considered a target species for domestication and conservation efforts. Despite several attempts of artificial reproduction and larval rearing, little is known on larval and early juvenile development of silver therapon. The presently reported study was therefore intended to fill this gap in the knowledge by determining the growth and describing body proportions, pigmentation, and fin formation of this fish. Newly hatched larvae were reared in mesocosm tanks at a mean temperature of 29.5°C. Larvae up to 30 days after hatching were sampled at irregular intervals and preserved in 5% buffered formalin. Early development stages for 245 preserved specimens were described in detail with reference to changes in morphology, growth and body proportions, pigmentation, and fin formation. Five developmental stages of silver therapon were identified: yolk sac larva (1.88 mm TL), preflexion (2.51 mm TL), notochord flexion (4.50-8.27 mm TL), postflexion larva (6.90-12.21 mm TL), and early juvenile (>13.40 mm TL). Growth was isometric for eye diameter and gape size whereas positive allometry was observed for body depth, head length, and preanal length. Some body proportions showed abrupt changes from preflexion to postflexion larvae before it stabilized during the early juvenile stage. Pigmentation in the form of stellate and punctate melanophores increased with developmental stage, with larvae becoming heavily pigmented from postflexion to early juvenile stage. These morphological changes, together with the full complement of fin rays and squamation observed in specimens larger than 13.4 mm TL, suggest the attainment of the juvenile stage of this species. These morphological changes may explain the food and feeding habits during the early life stages of silver therapon which is critical to their survival and recruitment in the wild and in a mesocosm hatchery environment.
    • Article

      Larval and early juvenile fishes associated with milkfish fry at Malandog, Hamtik, Antique 

      VC Banada - Fisheries Research Journal of the Philippines, 1983 - Fisheries Research Society of the Philippines
      From 5 May 1981 to 7 November 1981 a total of 122,841 specimens of milkfish fry and early juvenile fishes was collected with the use of a milkfish fry sweeper. Of these, 66,361 or 54.02% consisted of early juvenile stages of 30 species of finfish and the rest were 56,480 milkfish fry of 45.98% of the total collection.

      The most abundant finfish excluding milkfish fry was Ambassis sp. comprising 59.43% of the total fish catch, followed by Elops machnata, 12.7%; Sillago sihama, 8.66% Gobiidae, 6.11%; Therapon jarbua, 5.49% Stolephorus sp., 2.06%; Chonoporus sp., 1.53%; Mullet, 0.97% and Scatophagus argus, 0.32%. The rest of the species combined comprised less than 1%.

      Water temperature, pH and dissolved oxygen (D.O.) showed inverse relationships with fish abundance at the early hours of the day (0800H-1200H) but incosistent correlations were noted during night time when these parameters were rather constant. Salinity did not show any correlation to fish abundance although more species were collected after a heavy downpour. Fish catch was higher during low tide than at high tide.
    • Conference paper

      The larval and juvenile fish community in Pandan Bay, Panay Island, Philippines 

      T Bagarinao & Y Taki - In T Uyeno, R Arai, T Taniuchi & K Matsuura (Eds.), Indo-Pacific Fish Biology: Proceedings of the Second International Conference on Indo-Pacific Fishes: Conducted at the Tokyo National Museum Ueno Park, Tokyo, July 29-August 3, 1985, 1986 - Ichthyological Society of Japan
      Long-term (1975-1977) collections of larval and juvelnile fish were made from 1) onshore, a sandy beach flanked by a coral terrace and a river mouth, and 2) 500m offshore in 30 m deep water in Pandan Bay. About 70 species in 47 families were recorded onshore and 120 specis in 74 families were recorded offshore over the two-year period. About 60 species were common to both stations. Metamorphic stage Mugilidae dominated the onshore catch (75% of 587 samples), followed by Ambassis ssp. (55%) and Chanos chanos (48%). Predominant in the offshore station were larval Stolephorus spp. and Sardinella spp., occurring in 79% and 62% of 345 samples, respectively. Apogonidae, Leiognathidae, Gobiidae, Dussumieria sp., Caesio spp., Upeneus spp. larval, and the neotenic fish, Schindleria praematura, each occured in 20-40% of the offshore samples. Siganus spp., Lutjanus spp., Sphyraena spp. occured in considerable numbers onshore. Offshore, the first two species occured in higher, and the latter two in lower relative abundance. Mugilidae and Chanos chanos were also relatively less abundant offshore. Larvae of many inshore and pelagic fishery species like Carangidae, Scombridae and Bothidae occured at the offshore station together with larvae of coral reefs species like Pomacentrus spp. and the mesopelagic species like Benthosema spp. and Lestidiops sp.