Now showing items 3103-3122 of 3185

    • Article

      Vaccination of European sea bass fry through bioencapsulation of Artemia nauplii 

      M Chair, RSJ Gapasin, M Dehasque & P Sorgeloos - Aquaculture International, 1994 - European Aquaculture Society
      European sea bass (Dicentrarchus labrax) fry vaccinated orally via bioencapsulation in Artemia nauplii or by bath method exhibited better performance than control fish in terms of growth, food conversion and resistance to stress. The comparable survival between vaccinated and non-vaccinated animals suggests that vaccination methods are not stressful. The present study shows that oral vaccination can be used to enhance growth in fish fry.
    • Article

      Valine requirement of postlarval tiger shrimp, Penaeus monodon Fabricius 

      OM Millamena, MN Bautista-Teruel & A Kanazawa - Aquaculture Nutrition, 1996 - Wiley-Blackwell
      The valine requirement of juvenile tiger shrimp, Penaeus monodon Fabricius, was determined. Shrimp postlarvae, PL20, with a mean weight of 14 mg, were randomly distributed in 36 oval 40-L capacity fibreglass tanks at 10 shrimp per tank in a flow-through seawater system and reared for 8 weeks. Postlarvae were fed amino acid test diets containing 400 g kg−1 protein with casein and gelatine as intact sources of protein. Crystalline L-amino acids were supplemented to simulate the amino acid profile of the shrimp muscle except valine. Valine was added in graded levels to obtain 7, 10, 13, 16, 19 and 22 g kg−1 of the diet or 18, 25, 33, 40, 48 and 55 g kg−1 of dietary protein. At termination of the feeding experiment, growth and survival were determined and nutritional deficiency signs noted. The relationship between weight gain and dietary valine level was analysed by the broken-line regression method to derive the valine requirement. The dietary valine requirement of Penaeus monodon postlarvae was found to be 13.5 g kg−1 of the diet or 34 g kg−1 of dietary protein. This value was lower than the level found in the shrimp tissue.
    • magazineArticle

      The value of mangroves 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1995 - SEAFDEC Aquaculture Department
      The article presents the forestry, fishery and ecological values of mangroves. Studies on the measurement of the economic value of mangroves that were conducted in Thailand, Indonesia and Ecuador are also presented.
    • magazineArticle

      Value-added shrimp product is tops: Market potential 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1995 - SEAFDEC Aquaculture Department
      The article discusses the potential for export of value-added shrimp products from developing countries. European Economic Community is considered to be one of the top consumers, while Thailand and India are two of the top producers.
    • magazineArticle

      Value-adding through coatings 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1995 - SEAFDEC Aquaculture Department
      The paper presents the three categories of food coatings that are used, individually or in combination, to produce battered or breaded foods. These are predust, batters and breadcrumbs. Predusts are usually a blend of flours, starches and other functional ingredients such as proteins, vegetable gums and seasonings or flavors; batters are blends of flours, starches, leavening agents and seasonings which, when mixed with water, forms a vicous liquid used to evenly coat a food item, while breadcrumbs are baked or otherwise thermally processed cereal-based ingredients which are applied to a moistened food item prior to cooking.
    • Article

      Variation in the biochemical composition of Penaeus monodon tissues during the reproductive cycle. 

      V Dy-Peñaflorida & OM Millamena - The Israeli Journal of Aquaculture-Bamidgeh, 1990 - Bamidgeh
      The gonadosomatic index (GSI) and the hepatosomatic index (HSI) were determined for wild-caught, eyestalk ablated Penaeus monodon at 5 reproductive stages (I to V). Tissues of the muscle, ovary and hepatopancreas in each stage were analyzed for crude protein and amino acid composition.

      Results showed that the GSI increased from stage I (immature) to IV (fully mature) but declined at stage V (spent) while the HSI did not change significantly (P less than or equal to 0.05). Muscle protein content did not vary markedly from stage I to V except for a slight lowering at stage III (late maturing). Ovarian protein increased from stage I to IV and decreased at stage V while from stage II, the reverse was true for hepatopancreas.

      Generally, few significant differences in amino acid content were found. Glutamic acid content significantly differed among stages in all three tissues. In addition, phenylalanine in the muscle, histidine and lysine in the ovary and arginine and luecine in the hepatopancreas differed among stages. The muscle had slightly higher arginine and gluatmic acid contents than the ovary and hepatopancreas but was lower in threonine and valine. The ovary had the lowest glycine content.

      Results showed similar amino acid levels among tissues and maturation stages, suggesting that amino acids are fixed and not affected by much variation.
    • Article

      Variation in the vertebral number of the milkfish Chanos chanos, collected from various localities 

      T Senta & S Kumagai - Bulletin- Faculty of Fisheries Nagasaki University, 1977 - The Faculty of Fisheries, Nagasaki University
      A total of 2497 milkfish fry were collected in 1976 from nine localities in six countries, viz. India, Thailand, Indonesia, Philippines, Taiwan and Tahiti. Vertebra counts ranged from 40 to 45. The general trend of geographical gradient in vertebral counts in the milkfish was observed to be lower in the west (or otherwise, along continents) and higher in the east (or around oceanic islands). Extremes in the means of vertebral counts by localities were seen in the samples from India with 43.08 and from Tahiti with 43.82. It was suggested that there may be at least four subpopulations among the milkfish throughout the tropical Indo-Pacific waters.
    • Oral presentation

      Variation in tissue lipid content and fatty acid composition during ovarian maturation of unablated and ablated Penaeus monodon broodstock. 

      OM Millamena, R Pudadera & MR Catacutan - In Y Taki, JH Primavera & JA Llobrera (Eds.), Proceedings of the First International Conference on the Culture of Penaeid Prawns/Shrimps, 4-7 December 1984, Iloilo City, Philippines, 1985 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The tissue lipid content and fatty acid composition in the hepatopancreas, tail muscle and gonad of unablated and ablated Penaeus monodon were determined. Females at various stages of maturity were collected from offshore spawning grounds in Tigbauan and Guimbal, Iloilo, Philippines. Ablated females were reared in captivity.

      The hepatopancreas showed the highest lipid content at 15.72 to 25.20% in unablated females and 22.47 to 34.90% in ablated females. Fresh lipid levels averaged 2.60% with no marked variation throughout the maturation period. Ovarian lipid increased from 5.80% (unablated) and 7.50% (ablated) in Immature Ovaries to more than two-fold in Early Maturing Ovaries coupled with a drop in hepatopancreatic lipid suggesting lipid mobilization to the ovaries. In ablated females, ovarian lipid progressively increased to a maximum of 21.90% in Fully Mature Ovaries with a corresponding rise in hepatopancreatic lipid. Both the ovarian and hepatopancreatic lipids declined in spent females. Fatty acid profiles of the tissues consistently showed the presence of polyunsaturated fatty acids (PUFA) 20:4ω6, 20:5ω3 and 22:6ω3. These fatty acids were reflected in the spawned egg. The lipid level in the hepatopancreas appeared to be inversely related to the total PUFA concentration in the ovaries. Lipid accumulation in ablated females was significantly higher than in unablated females.

      The findings suggest storage and subsequent utilization of lipids for maturation and spawning processes. The type of polyunsaturates present in the maturing ovaries is indicative of their metabolic and physiological importance in the reproductive process.
    • Meeting report

      Verification of semi-intensive shrimp culture techniques: Myanmar. 

      M Thame - 2004 - Aquaculture Department, Southeast Asian Fisheries Development Center
      In the year 2000, the Ministry of Livestock and Fisheries reinforced and encouraged many potential investors to be involved in the shrimp aquaculture development in the country. At the same time, the Union of Myanmar formed a State Level Committee to promote a drastic development of the shrimp aquaculture industry by formulating a three-year concept plan from May 2000 to May 2003 with a target to develop 120,000 acres (48,000 hectares) of shrimp pond areas at the end of the target period. Since then a lot of potential investors were involved in shrimp aquaculture practicing semi-intensive and intensive type of shrimp farming.

      In 2002, some shrimp farms practicing semi-intensive/intensive system had successes but some encountered white spot disease occurrence resulting in great losses. The disease had devastated many farms in Yangon Division, paralyzing the shrimp industry development. In Yangon, the water is very turbid and the farms are near the urban waste dumping area.

      Through the Project, three areas were surveyed in February 2001 to determine the level of shrimp technology that Myanmar has developed for shrimp farming. The three areas were: (1) Thi La Wa Shrimp Culture Zone (Kyauktan Township); (2) Chaungta (Kyauktan Township); and (3) Ngwe Saung area. Results of the survey were used to identify the areas that could be used for the Project.
    • Meeting report

      Verification of semi-intensive shrimp culture techniques: Vietnam. 

      L Xan - 2004 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Vietnam has about 260,000 ha devoted for shrimp culture in early 1999. The total production was estimated at about 80,000 tons in 2000, so that productivity was about 300 kg/ha only. In 1990–1997, vast areas of mangroves were destroyed by many fish farmers for conversion into shrimp culture ponds. The Vietnam Government and local authorities have been trying to mobilize and educate farmers for them to refrain from destroying mangroves for shrimp culture; and at the same time promote increased shrimp productivity/ha in order to increase profit; and generate employment without necessarily destroying the mangroves.

      Cathai is an island district in north Vietnam with 12 communes in two islands, Catba and Cathai. Phulong Island in Catba Island, has the largest mangrove area. Before 1990, the total mangrove area of Phulong was about 2000 ha but in 1998 only about 1200 ha remained, because about 800 ha had been converted into shrimp ponds.

      However, due to lack of technology in shrimp culture especially the semi–intensive pond culture, production ranged from 200 to 300 kg/ha/crop, while in extensive ponds, production was only 50–70 kg/ha/year. Local authorities and the people of Phulong have been expecting to increase productivity from shrimp culture. Using the mangrove-friendly shrimp technology modeled by the Philippines and Thailand, the objective of the semi–intensive shrimp pond culture activity in Vietnam is to obtain 1000–1500kg/ha and to develop a model for an improved shrimp culture system.

      In the Memorandum of Agreement signed between the Ministry of Fisheries and the Southeast Asian Fisheries Development Center for the implementation of the Project in Vietnam, the Research Institute for Marine Products (RIMP) in Haiphong was chosen to carry out the demonstration activity focusing on the semi–intensive mangrove-friendly shrimp culture in Phulong, Cathai District, Haiphong, Vietnam. The ponds used for the Project had a total area of about 6.0 ha. Construction of the pond facilities following the Project’s scheme was completed in December 1999.
    • Article

      Vertical distribution of euthecosomatous pteropods in the upper 100m of the Hilutangan Channel, Cebu, The Philippines 

      NB Solis & H Westernhagen - Marine Biology, 1978 - Springer-Verlag
      The vertical distribution of euthecosomatous pteropods in the upper 100 m of the Hilutangan Channel, Cebu, The Philippines was studied, based on 126 samples, comprising 47, 282 individuals. Thirty-min horizontal plankton tows were performed at depths of 1, 20, 50, 70 and 100 m in January and February 1972. Thirteen species -including 3 subspecies - of juvenile and adult euthecosomes were identified. In decreasing order of abundance the species are: Creseis acicula (20.4%), Limacina trochiformis (19.9%), Creseis virgula constricta (14.6%), L. inflata (10.5%), Clio pyramidata (9.9%), Creseis virgula conica (8.9%), L. bulimoides (7.3%), Diacria quadridentata (5.3%), Cavolinia longirostris (1.9%), Creseis virgula virgula (1.0%), Hyalocylix striata (0.1%), Cuvierina columella (0.08%), Cavolinia uncinata (0.002%). In 3 species, a large percentage were juveniles; for 1 species, Clio pyramidata , only juveniles were caught. The Vertical species distribution was similar to the distribution of the respective species in Caribbean and Bermuda waters. Temperature, salinity and dissolved oxygen influence vertical distribution little, if at all.
    • Article

      Vertical diurnal migration of Daphnia cucculata and Eudiaptomus graciloides in eutrophic Frederiksborg Castle Lake, Denmark. 

      MH Carlos - Kalikasan, The Journal of Philippine Biology, 1982 - University of the Philippines at Los Baños
      In euthrophic Frederiksborg Castle Lake, Berg & Nygaard were the first to study vertical migration. They obtained water samples at various time intervals over several days and concluded that the bulk of the population of the zooplankton they were studying shifted from one depth to another. D. cucculata and E. graciloides are the two most dominant zooplankters in Frederiksborg Castle Lake. The vertical migration of these species was studied, and the observations are reported in this paper.
    • Article

      Vertical rope cultivation of Gracilaria (Rhodophyta) using vegetative fragments 

      AQ Hurtado-Ponce - Botanica Marina, 1990 - Walter de Gruyter
      Preliminary field culture of Gracilaria using vegetative fragments inserted between braids of ropes suspended vertically inside a floating cage was undertaken to assess the daily growth rate and monthly yield as influenced by three different spacing intervals.

      Daily growth rate of cuttings at 10 cm intervals ranged from 0.6 to 7.2% with yields of 11 to 415 g m-1 line1, those at 15 cm from 1.4 to 9.1% with yields of 18 to 502 g m-1 line-1, and at 20 cm from 1.7 to 10.5% and with yields of 20 to 379 g m-1 line-1. Both growth and yield were minimum in December at all spacing intervals but maximum in April at 10 and 15 cm and in February at 20 cm.

      Results of the analysis of variance (ANOVA) showed a non-significant interaction between spacing interval and culture month on daily yield of Gracilaria. This indicates that the effect of spacing interval on the daily growth rate and monthly yield was not significantly influenced by the culture month; likewise the effect of culture month did not differ significantly with the intervals used. The main effects, however, of spacing interval and culture month to daily growth rate were significant. Yield was significantly affected by the culture month but not by spacing interval.
    • Article

      Viability of a bottom-set tray ocean nursery system for Holothuria scabra Jaeger 1833 

      JRC Gorospe, JP Altamirano & MA Juinio-Meñez - Aquaculture Research, 2017 - Wiley
      Scaling up the hatchery production of juvenile sandfish Holothuria scabra is constrained by limited hatchery space and the associated high operational costs. To shorten the hatchery rearing phase, ocean nursery systems like floating hapa nets have been used with good prospects but with limitations during rough sea conditions. In this study, the potential of bottom‐set trays (0.14 m2) as an alternative ocean nursery system for early sandfish juveniles (0.5 ± 0.1 cm) was evaluated. The effects of stocking density and presence of artificial substrates (AS) on the growth and survival were determined in a 60‐day field experiment. Average length and growth rates at lower stocking density treatment (100 individuals tray-1) were significantly higher (1.45 ± 0.22 cm; 0.03 ± 0.01 cm day-1) than at higher stocking density treatments (400 and 500 individuals tray-1) 0.95 ± 0.06 cm; 0.03 ± 0.004 cm day-1) with or without AS (p < .05) respectively. The coefficient of variation in length (CV) at high stocking densities were significantly higher than at low densities (p < .05) and growth rate was strongly negatively correlated with density. Survival was significantly higher (55% ± 9%) in trays with AS across all stocking density treatments than in trays without AS (34% ± 2%). Results suggest that AS may have reduced intra‐ and interspecific interactions, resulting to significantly lower growth variations and higher survival. The bottom‐set tray with AS can be a practical alternative ocean nursery unit for rearing early sandfish juveniles particularly when the sea surface condition is rough. With improved design and density management, survival and growth may be further enhanced.
    • Article

      Viability of frozen algae used as food for larval penaeids 

      E Aujero & O Millamena - SEAFDEC Aquaculture Department Quarterly Research Report, 1979 - SEAFDEC Aquaculture Department
      Freezing with added chemicals as flocculants and protectants was assessed as a means of preserving stock cultures of 4 algal species used for larval penaeid food Chaetoceros calcitrans, Skeletonema costatum, Tetraselmis chuii and Isochrysis galbana . The maximum storage effectability of the preservation techniques for each species was also determined.
    • Article

      Viability of frozen algae used as food for larval penaeids 

      E Jereos-Aujero & OM Millamena - Fisheries Research Journal of the Philippines, 1981 - Fisheries Research Society of the Philippines
      Freezing with added chemicals as flocculants and protectants as means of preserving stock cultures was tried with four species commonly used as larval food. The species were Chaetoceros calcitrans, Skeletonema costatum, Tetraselmis chuii , and Isochrysis galbana.

      Except in I. galbana , this method successfully preserved the viability of the algae tested. C. calcitrans , was viable up to eighteen months storage; T. chuii , four months; and S. costatum , two months.

      Cryophylaxis did not seem to greatly increase the viability of frozen cells except with T. chuii ; however, with the diatoms, viability was preserved regardless of the harvesting flocculant used and whether or nor protectants were added.
    • Conference paper

      Viability of milkfish eggs and larvae after simulated and actual transport 

      JD Toledo, M Doi & M Duray - In D MacKinlay & M Eldridge (Eds.), The Fish Egg: Its Biology and Culture Symposium Proceedings. International Congress on the Biology of Fishes, 14-18 July 1996, San Francisco State University, 1996 - American Fisheries Society, Physiology Section
      The viability of milkfish eggs and larvae after simulated and actual transport was investigated. Naturally-spawned milkfish eggs were collected and subjected to simulated or actual transport at early cleavage stage (stage 1), blastula (stage 2), gastrula (stage 3), "eyed" (stage 4), or newly-hatched larvae (stage 5). Replicate samples in aerated plastic jars served as controls. Mean hatching and survival rates and the percentage of newly-hatched larvae were significantly affected by the modes of transport and by the stage of embryonic development at transport. Eggs transported at the 'eyed' stage had higher viability compared to those transported at cleavage, blastula, or gastrula stages. There was no significant difference in the mean survival rate of the larvae after 26 days of rearing. However, the percentage of 45 day old larvae with apparent morphological abnormalities was lower in groups transported at stages 4 and 5. These observations indicate that milkfish eggs should be handled and transported during the late embryonic stages to minimize mortalities and the incidence of abnormalities in larvae.
    • Article

      Viability of Penaeus monodon eggs after simulated transport conditions 

      JH Primavera, E Borlongan & RA Posadas - SEAFDEC Aquaculture Department Quarterly Research Report, 1977 - SEAFDEC Aquaculture Department
      P. monodon spawners, transported from maturation pens suffer from stress which in turn may lead to lowered spawning rate or fertility. Spawning the females in the maturation site and transporting the eggs to the hatchery site is being considered as an alternative. Egg transport costs may be reduced to a minimum by using eggs from ablated spawners, transported at high density with no aeration. Experiments on higher egg densities as well as on transport of nauplii should, however, be undertaken.
    • Conference paper

      Vibrio harveyi and the 'green water culture' of Penaeus monodon. 

      GD Lio-Po, EM Leaño, RC Usero & NG,J Guanzon - In Y Inui & ER Cruz-Lacierda (Eds.), Disease Control in Fish and Shrimp Aquaculture in Southeast Asia – Diagnosis and Husbandry Techniques: Proceedings … Aquaculture in Southeast Asia – Diagnosis and Husbandry Techniques, 4-6 December 2001, Iloilo City, Philippines, 2002 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The 'green water culture' of the tiger shrimp, Penaeus monodon, is an innovative culture technique for the grow-out rearing of shrimps. This culture method involves the use of rearing water of tilapia for the rearing of tiger shrimp in grow-out ponds and on the polyculture of shrimp with tilapia. This culture technique was reported to present disease outbreaks attributed to luminescent Vibrio. To understand the possible mechanisms of luminous Vibrio control in the green water culture system several studies were conducted. This review summarizes the highlights obtained so far from these studies consisting of a) effect of rearing waters from tilapia culture and shrimp cultured with tilapia on Vibrio harveyi; b) estimation and preliminary identification of cultivable bacteria, fungi and phytoplankton flora associated with the 'green water culture' system and c) detection of anti-Vibrio harveyi metabolites from bacteria, yeast, filamentous fungi and phytoplankton indigenous to the 'green water culture' system.