Now showing items 1-20 of 1051

    • Article

      Abdominal segment deformity syndrome (asds) and fused body segment deformity (fbsd) in cultured Penaeus indicus 

      The abdominal segment deformity disease (ASDD) is a new shrimp disease reported only in cultured Penaeus vannamei in Thailand. Shrimp with ASDD have deformed abdominal segment, jagged gut line and bumpy surfaces. Similar signs were observed in cultured P. indicus in the Philippines. However, aside from the signs described for ASDD, some P. indicus showing abdominal segment deformity syndrome (ASDS) had more severe deformities up to the extent that the number of body segments was reduced due to fusion. Shrimp with fused body segment deformity (FBSD) had four instead of five pairs of legs. To account the prevalence of the deformities in P. indicus, shrimp were classified into grossly normal shrimp (NS), shrimp with abdominal segment deformity syndrome (ASDS) and shrimp with fused segments (FBSD). Out of the shrimp sampled, 83.4 ± 5.4% was NS, 10.9 ± 6.2% was ASDS and 5.7 ± 3.0% was FBSD. Morphometric characteristics of the shrimp were measured. There was no significant difference in body weight (BW) among male and female NS, ASDS and FBSD. In both sexes, total length (TL) of FBSD was significantly shorter compared to NS and ASDS. Shrimp samples were also screened to be negative for known infectious viral diseases including white spot syndrome virus (WSSV), infectious hypodermal and haematopoietic necrosis virus (IHHNV), infectious myonecrosis virus (IMNV), P. vannamei nodavirus (PvNV), Macrobrachium rosenbergii nodavirus (MrNV) and Taura syndrome virus (TSV). Occurrence of ASDS and FBSD in post-larvae (PL) produced from captive and wild spawners were also determined. Based on a tank experiment, no significant difference was detected between the percentages of ASDS in PL produced from wild or captive spawners but FBSD was only noted in PL produced from the latter. Deformities generally did not affect the size of P. indicus except for the reduced length of shrimp with FBSD which when coupled with missing pleopods could lead to major economic loss for shrimp farmers if not addressed properly.
    • Article

      Acceptability of territorial use rights in fisheries: towards community-based management of small-scale fisheries in the Philippines 

      SV Siar, RF Agbayani & JB Valera - Fisheries Research, 1992 - Elsevier
      The granting of territorial use rights in fisheries (TURFs) to fisherfolk associations, similar to that practiced in Japan, is recommended as a management tool for small-scale fisheries in the Philippines. This study, carried out to determine the acceptability of the practice under Philippine conditions, was conducted among 211 coastal dwellers of five municipalities in Panay Island, Central Philippines. Respondents of the survey generally perceived the practice of TURFs as acceptable as it would lead to an improvement of their catch. Results suggest that the respondents' present predicament of inadequacy of catch to support their livelihood is the starting point for introduction of the rationale for community-based management of coastal marine resources.
    • Article

      Acclimation of Penaeus monodon postlarvae to fresh water 

      JB Pantastico & EN Oliveros - Fisheries Research Journal of the Philippines, 1980 - Fisheries Research Society of the Philippines
      Gradual acclimation of Penaeus monodon Fabricius to fresh water was conducted in glass aquaria and marine plywood tanks over a one-day, two-day, and three-day acclimation periods. Different stages of postlarvae were tested for their hardiness to acclimation. P35 postlarvae had a high percent survival of 98-99% while lower values were obtained for P20 and P90. A three-day acclimation period was favorable for all ages of postlarvae. Shorter durations of acclimation produced survival values as low as 20% This stress effect was apparent with P20 and P90 but not with P35 which showed high survival regardless of the length of acclimation.
    • Article

      Accumulation and excretion of metal granules in the prawn, Penaeus monodon, exposed to water-borne copper, lead, iron and calcium 

      G Vogt & ET Quinitio - Aquatic Toxicology, 1994 - Elsevier
      Juveniles of the giant tiger prawn, Penaeus monodon, were exposed for 10 days to 1 mg/l copper, lead, iron or calcium in order to investigate the formation and accumulation of metal granules in major soft tissues as well as their excretion from the body. Metal deposition was investigated by histochemistry and electron microscopy in the hepatopancreas and surrounding organs and tissues like the stomach, midgut, anterior midgut caecum, thoracal antennal gland extensions, haematopoietic tissue, and interspersed musculature, connective tissue and pigment tissue. The abundance of metal granules varied greatly between the metals and the tissues. Iron and calcium deposits were found in none of the tissues investigated. Copper granules were accumulated in high quantity in the hepatopancreas tubules, were scarce in the antechamber of the hepatopancreas, the anterior midgut and the anterior midgut caecum, and were lacking in the other tissues. The amount and size of copper granules increased along the hepatopancreas tubules in accordance with the cells' age. The granules were released by discharge of senescent hepatopancreas cells in the antechamber region and were added to the faeces. Lead granules were primarily found in the thoracal extensions of the antennal gland. In the hepatopancreas they occurred only in very small quantities, and in the other organs and tissues they were absent. In the antennal gland, the lead granules were individually discharged into the gland lumen by apocrine secretion and excreted with the urine. The observed ability of Penaeus monodon to detoxify and remove metals like copper and lead by granule formation and excretion and to prevent other metals like iron from entrance into major soft tissues corroborate that decapods are no suitable organisms for a long-term biomonitoring of heavy metal pollution.
    • Article

      Accumulation and tissue distribution of radioiodine (131I) from algal phytoplankton by the freshwater clam Corbicula manilensis 

      MLA Cuvin-Aralar & RC Umaly - Bulletin of Environmental Contamination and Toxicology, 1991 - Springer Verlag
      Radioactive wastes discharged from establishments involved in the use of radioisotopes such as nuclear powered industries, tracer research and nuclear medicine are a potential public health hazard. Such wastes contain radionuclides, particularly Iodine-131 (131I), produced in fission with a yield of about 3%. It is a beta emitter (Bmax = 0.61MeV); it also emits gamma photons. It has a short half-life (8.04 d) (Dutton 1975), hence it is difficult to detect unless accumulated by indicator organisms.

      Radionuclides in waste waters are known to be taken up by molluscs such as mussels (Van der Borght and Van Puymbroeck 1970; Fowler et al. 1975; Hetherington et al. 1976; Helt et al. 1980; and Sombrito et al. 1982), oyster (Romeril 1971; Cranmore and Harrison 1975) and clams (Cuvin and Umaly 1988).

      This study aims to determine the uptake of 131I from algal phytoplankton (Choroococcus dispersus) fed to the freshwater clam Corbicula manillensis as well as the organ/tissue distribution. The results will be compared with our previous study on 131I uptake from water by the same clams (Cuvin and Umaly 1988).
    • Article

      Acute hepatopancreatic necrosis disease (AHPND) outbreaks in Penaeus vannamei and P. monodon cultured in the Philippines 

      LD de la Peña, NAR Cabillon, DD Catedral, EC Amar, RC Usero, WD Monotilla, AT Calpe, DD Fernandez & CP Saloma - Diseases of Aquatic Organisms, 2015 - Inter Research
      Acute hepatopancreatic necrosis disease (AHPND) has recently emerged as a serious disease of cultured shrimp. It has also been described as early mortality syndrome (EMS) due to mass mortalities occurring within 20 to 30 d after stocking of ponds with postlarvae. Here, Penaeus vannamei and Penaeus monodon from shrimp farms in the Philippines were examined for the toxin-producing strain of Vibrio parahaemolyticus due to AHPND-like symptoms occurring in marketable size shrimp. In the P. vannamei, histology revealed typical AHPND pathology, such as sloughing of undifferentiated cells in the hepatopancreatic tubule epithelium. Analysis using the IQ2000 AHPND/EMS Toxin 1 PCR test generated 218 bp and 432 bp amplicons confirmative of the toxin-producing strain of V. parahaemolyticus among shrimp sampled from 8 of 9 ponds. In the P. monodon, histology revealed massive sloughing of undifferentiated cells of the hepatopancreatic tubule epithelium in the absence of basophilic bacterial cells. PCR testing generated the 2 amplicons confirmatory for AHPND among shrimp sampled from 5 of 7 ponds. This study confirms the presence of AHPND in P. vannamei and P. monodon farmed in the Philippines and suggests that the disease can also impact late-stage juvenile shrimp.
    • Article

      Acute nitrite toxicity and methemoglobinemia in juvenile milkfish (Chanos chanos Forsskal) 

      JME Almendras - Aquaculture, 1987 - Elsevier
      Nitrite was about 55 times more toxic to milkfish juveniles in fresh water than in 16% brackish water: the 48-h median lethal concentrations were 12 mg NO2-N/l (95% confidence limit=7.4–19.6) and 675 mg NO2-N/l (95% confidence limit = 435.8–1,045.4) respectively. Methemoglobin levels were higher for a given concentration of nitrite in milkfish kept in fresh water than in the brackish water. Methemoglobin decreased to a normal level within 24–26 hours of the removal of nitrite.
    • Article

      Acute toxicity of nifurpirinol, a fish chemotherapeutant, to milkfish (Chanos chanos) fingerlings 

      CT Tamse & RQ Gacutan - Bulletin of Environmental Contamination and Toxicology, 1994 - Springer Verlag
      Nifurpirinol (trade name Furanace and originally known as P-7138), is a nitrofuran derivative synthesized by the Dainippon Pharmaceutical Co. Ltd., Japan, and was developed exclusively as a broad-spectrum antibiotic for fish and other aquatic organisms (Shimizu and Takase 1967). It has been shown to have bactericidal and fungicidal action in vitro and in vivo (Shimizu and Takase 1967; Amend and Ross 1970; Pearse et al. 1974; Mitchell and Plumb 1980), and was used because of its excellent potential in controlling prawn diseases (Delves-Broughton 1974; Gacutan and Llobrera 1977).

      Milkfish (Chanos chanos Forsskal) is a widely-reared species and a very important aquaculture food crop in most parts of Southeast Asia. Thus, it was the logical choice as test animal for investigating the LC50 toxicity levels of nifurpirinol (6-hydroxymethyl-2-[2-(5-nitro-2-furyl) vinyl] pyridine) after 96 hr exposure. Changes in the normal gill architecture of milkfish after exposure to the drug were also studied (Tamse et al., in preparation).
    • Article

      Acute toxicity of nitrite to mud crab Scylla serrata (Forsskål) larvae 

      ML Seneriches-Abiera, F Parado-Estepa & GA Gonzales - Aquaculture Research, 2007 - Blackwell Publishing
      Early larval stages of mud crab Scylla serrata were exposed to different concentrations of nitrite (40, 80 and 160 mg L−1 and a control, without added nitrite) and three salinity levels (25, 30 and 35 g L−1) using a static renewal method. No interactive effect of nitrite and salinity was detected. Estimated LT50 in 96-h toxicity tests decreased in all stages with increasing nitrite concentrations in all salinity levels. The 96-h LC50 values of nitrite-N were 41.58, 63.04, 25.54, 29.98 and 69.93 mg L−1 for zoea 1, 2, 3, 4 and 5 respectively. As the larvae grew, they showed a progressive increase in tolerance to nitrite. The toxicity of nitrite to larvae increased with exposure time. The median lethal concentration was not affected by salinity. The chloride component of salinity within 25–35 g L−1 did not seem to be as effective in alleviating toxicity as has been reported in other crustacean species. Based on 96-h LC50 and an application factor of 0.1, the ‘safe level’ of rearing mud crab larvae was calculated to be 4.16, 6.30, 2.55, 2.99 and 6.99 mg L−1 nitrite-N for zoea 1, 2, 3, 4 and 5 respectively.
    • Article

      Acute toxicity of potassium permanganate to milkfish fingerlings, Chanos chanos 

      ER Cruz & CT Tamse - Bulletin of Environmental Contamination and Toxicology, 1989 - Springer Verlag
      Potassium permanganate (KMnO4) is a strong oxidizing agent and is commonly used in aquatic systems to improve available oxygen, treat infectious diseases and parasites, detoxify fish poisons, and control algae. The following study was undertaken to determine the 24- and 96-h median lethal concentration (LC50) of milk fish (Chanos chanos)) fingerlings to KMnO4. The study was also designed to evaluate the histopathological response of fish tissues to KMnO4 but was reported in another paper (Cruz and Tamse 1986).
    • Article

      Acute toxicity of un-ionized ammonia to milkfish (Chanos chanos) fingerlings 

      ER Cruz - Fisheries Research Journal of the Philippines, 1981 - Fisheries Research Society of the Philippines
      The acute toxicity of un-ionized ammonia to milkfish (Chanos chanos) fingerlings was determined using a static bioassay system. The 24-, 48-, 72-, and 96-hr LC50 values were calculated at 25.74 ppm NH3-N (1.89 ppm NH3), 23.06 ppm NH3-N (1.46 ppm NH3), 21.62 ppm NH3-N (1.25 ppm NH3) and 20.65 ppm NH3-N (1.12 ppm NH3), respectively.
    • Article

      Acute toxicity of water-accommodated fraction and chemically enhanced WAF of bunker C oil and dispersant to a microalga Tetraselmis tetrathele 

      SS Santander-Avanceña, RB Sadaba, HS Taberna Jr., GT Tayo & J Koyama - Bulletin of Environmental Contamination and Toxicology, 2016 - Springer Verlag
      This study assessed the toxicity of water-accommodated fraction (WAF) and chemically enhanced WAF (CEWAF) of bunker C oil and dispersant (DISP) to a microalga, Tetraselmis tetrathele. The 72-h median effective concentration (72-h EC50) of CEWAF and DISP were determined at 3.30 % and 2.40 %, respectively. The no observed effect concentration (NOEC) of CEWAF to T. tetrathele was at 2.0 % and lowest observed effect concentration (LOEC) was at 3.0 % while NOEC and LOEC of DISP to T. tetrathele were determined at 1.0 % and 2.0 %, respectively. The addition of dispersant to oil increased the amount of total PAH present in the CEWAF test solutions. DISP alone was highly toxic, and the toxicity of CEWAF was primarily caused by the presence of dispersant.
    • Article

      Adsorption and biomass concentration of thraustochytrid Schizochytrium aggregatum (Goldstein and Belsky) in Bunker C Oil 

      BGS Sarinas, LD Gellada, MLT Torrigue, DN Sibonga, ES Torrato, JG Malagad, JG Feril, LAJ Bondoc, JCA Roncal & JA Tornalejo - Journal of Environmental Science and Management, 2014 - School of Environmental Science and Management, University of the Philippines Los Baños
      Diverse array of microorganisms such as bacteria, fungi and protists are involved during oil spill. Each microorganism has its own specific function whether it has to degrade or adsorb hydrocarbons. One important microorganism is the Thraustochytrid that is a fungoid protist and are common in marine and estuarine habitats. Numerous studies existed on the biodegradation and adsorption of Thraustochytrids on various substances but not on Bunker C oil. Thus, this study aimed to determine the adsorption capacity and mean biomass of Thraustochytrids in Bunker C oil using different cell densities measured in grams. All of the three treatments or cell densities (1 x 105 cells ml-1, 1 x 106 cells ml-1 and 1 x 107 cells ml-1) were triplicated and average values were recorded. Oil dispersant was used as a control. It showed that Thraustochytrid with 1 x 107 cells ml-1 showed the highest adsorbed oil (.057 ḡ) among the three cell densities and showed significant difference at p = .01 but comparable to the control (.066 ḡ). In terms of biomass concentration, all cell densities showed no significant difference at p = .01. Thraustochytrid is a promising tool during oil spill because it has the capacity to adsorb oil.
    • Article

      Advanced broodstock diets for the mangrove red snapper and a potential importance of arachidonic acid in eggs and fry 

      AC Emata, HY Ogata, ES Garibay & H Furuita - Fish Physiology and Biochemistry, 2003 - Springer Verlag
      Mangrove red snapper fed advanced broodstock diets containing squid meal and squid oil exhibited higher hatching rates, cumulative survival and survival activity index than those fed a basal diet or a basal diet supplemented with mixture of antioxidants. On the other hand, fatty acid analyses of ovaries and fry of wild fish and eggs and larvae of broodstock fed raw fish revealed high arachidonic acid (ARA) and docosahexaenoic acid (DHA) levels and relatively lower eicosapentaenoic acid (EPA) levels consequently showing high ARA/EPA and DHA/EPA ratios compared to cold water species. This suggests that ARA may be nutritionally more important for egg and larval development and survival in tropical marine fish and its supplementation in broodstock diets may enhance reproductive performance of mangrove red snapper.
    • Article

      Advancement of sexual maturation and spawning of sea bass, Lates calcarifer (Bloch), using pelleted luteinizing hormone-releasing hormone analogue and 17α-methyltestosterone. 

      LMB Garcia - Aquaculture, 1990 - Elsevier
      The ability of luteinizing hormone-releasing hormone analogue [(D-Ala6, Pro9-NEt)LHRH], 17α-methyltestosterone (MT), and their combination to advance gonadal maturation and spawning in captive sea bass (Lates calcarifer Bloch) broodstock was tested. Several hormonal therapies were tested including monthly implantations of a low dose (100 μg/kg body weight) of each hormone and a high dose (200 μg/kg) implanted to sexually-quiescent sea bass at 45-day intervals. A high dose of LHRHa alone or in combination with MT induced a significant number of mature females (43–71%) in April, 45 days after a single implantation in early March. A lower dose of pelleted LHRHa and LHRHa plus MT was found effective (78–80%) only in May following three monthly implantations. Two and three monthly implantations of a low dose of MT failed to stimulate oocyte growth in April and May whereas a less frequent mode of application of a high dose of the androgen inhibited ovarian growth in April only. A low dose of MT alone significantly increased the number of mature males in April (90%) and May (100%) after two and three monthly implantations. All male sea bass which received three monthly implantations of a low dose of LHRHa and LHRHa plus MT were sexually mature in May. Sexually mature sea bass obtained from these experiments spawned in early May after a single intramuscular injection of LHRHa. These results demonstrate the potential use of pelleted LHRHa and MT to significantly advance gonadal development and spawning in sea bass earlier than the annual breeding season.
    • Article

      Aeromonas hydrophila associated with ulcerative disease epizootic in Laguna de Bay, Philippines 

      AT Llobrera & RQ Gacutan - Aquaculture, 1987 - Elsevier
      Aeromonas hydrophila was consistently associated with necrotic ulcers and lesions in mudfish/snakehead (Ophiocephalus striatus), Thai catfish (Clarias batrachus), crucian carp (Carassius carassius) and goby (Glossogobius giurus) in Laguna de Bay, Philippines, during the months of December 1985 through February 1986. The bacterium was isolated from body lesions and ulcers of all fish examined and rarely from the kidney and liver of carp and catfish. The disease was characterized by hemorrhages, lesions and open necrotic ulcers on the body of the fish, particularly the head (just behind the eyes), the mandible and the maxilla, and the caudal peduncle regions. Erosion of the head bone tissues and the tails was observed in very severe cases. The presence of A. hydrophila is believed to be secondary to some predisposing factors existing in Laguna de Bay.
    • Article

      Aflatoxin B1 contamination of shrimp feeds and its effect on growth and hepatopancreas of pre-adult Penaeus monodon 

      MN Bautista, CR Lavilla-Pitogo, PF Subosa & ET Begino - Journal of the Science of Food and Agriculture, 1994 - Society of Chemical Industry
      A survey of aflatoxin B1 (AFLB1) levels in commonly used commercial shrimp finisher feeds in the Philippines showed a various range of values from not detected to 120 μg kg−1 using high-performance thin-layer chromatography. Six experimental diets were prepared to contain various levels of AFLB1 based on survey results to determine the effects of such contamination in pre-adult shrimp Penaeus monodon (17.5 ± 0.6 g). Results showed that shrimps fed diets containing AFLB1 greater than or equal to 73.8 μg kg−1 gave comparatively poor growth rate and higher susceptibility to shell diseases. No AFLB1 residues were detected in sampled whole shrimp tissues after 62 days of exposure to AFLB1 containing diets indicating a low potential for transmission of the toxin from edible shrimp tissues to consumers. Histopathological alterations in the hepatopancreas of shrimp chronically exposed to AFLB, were observed in all samples. The degree of alterations correlated with the level of AFLB1. Based on growth performance, pre-adult shrimps can tolerate AFLB1 levels of up to 52.3 μg kg−1 in the feeds although histopathological changes were already evident in the tissues of shrimps given diets with 26.5 μg kg−1 AFLB1.
    • Article

      Agar production from Gracilariopsis heteroclada (Gracilariales, Rhodophyta) grown at different salinity levels 

      AQ Hurtado-Ponce - Botanica Marina, 1994 - Walter de Gruyter
      Gracilariopsis heteroclada grown in fiber glass tanks at four salinity levels was treated with three different concentrations of aqueous NaOH. Yield, gel strength, gelling and melting temperatures of the extracted agar were determined. Plants grown at salinities of 24 and 32 ppt and treated with 3% NaOH produced the strongest gel (850 g cm-2) and weakest gel (300 g cm-2), respectively. Statistically significant differences in gel strength, dynamic gelling and melting temperatures were observed between the various treatments. The interactive effect of salinity and NaOH was significant in gel strength, gelling and melting temperatures of the gel from G. heteroclada.
    • Article

      Agar yield and gel strength of Gracilaria heteroclada collected from Iloilo, Central Philippines 

      MRJ Luhan - Botanica Marina, 1992 - Walter de Gruyter
      Seasonality of yield and gel strength of agar from Gracilaria heteroclada was determined. Gel strength was high (510-794 gm cm-2) during early dry season (October-March) and low (43-101 gm cm-2) during the wet season (May-August). A negative correlation exist (P ≤ 0.05) between agar yield and gel-strength.
    • Article

      Agar yield, gel strength and sulfate content in Gracilariopsis heteroclada farmed in brackishwater canals 

      TR de Castro - The Israeli Journal of Aquaculture-Bamidgeh, 1996 - Society of Israeli Aquaculture and Marine Biotechnology
      This paper aimed at determining the optimum NaOH pretreatment strength and duration and the monthly variations in gel strength, agar yield and sulfate content of agar from Gracilariopsis heteroclada (Zhang et Xia) farmed in brackishwater canals in Leganes, Iloilo, Philippines, during the dry season (October to March). The highest gel strength (641 g/cm2) and lowest sulfate content (7.66 µg/mg SO4) were obtained following pretreatment with 5% NaOH for 30 min. The agar yield from this treatment was 32.4% and negatively correlated with percent alkali used (r = -0.92465, p<0.05) and gel strength (r = -0.72711, p<0.05). The sulfate content was also negatively correlated with gel strength (r = -0.40911, p<0.05). The gel strength (274-622 g/cm2), agar yield (18.1-38.1%) and sulfate content (11.4-22.9 µg/mg) showed monthly variations. Water temperature ranged 30-35°C, salinity 26-32 ppt, and rainfall 39.4-561 mm. The agar yield was negatively correlated with temperature (r = -0.57286, p<0.05) and rainfall (r = -0.66435, p<0.05). Results showed that agar from G. heteroclada has very good potential for use as a raw material in the production of food, drug and industrial grades of agar because of its superior gel strength.