Zoea 2(Z SUB-2 ) Mysis 1 (M SUB-1 ) and Postlarva 1 (P SUB-1 ) of P. monodon artificially spawned... more Zoea 2(Z SUB-2 ) Mysis 1 (M SUB-1 ) and Postlarva 1 (P SUB-1 ) of P. monodon artificially spawned in closed-system concrete hatchery tanks were bioassayed for their tolerance to the antibiotic furanace. The setup consisted of four 20-liter capacity plastic basins previously conditioned for 15 days with freshwater in full sunlight. During the experiment, each basin was filled with 5 liters of seawater to which was added filtered Chaetoceros and Brachionus to give densities of 5 . 0-7 . 5 x 10 SUP-4 cells/ml and 10-20 individuals/ml, respectively. The following are the properties of the water used throughout the experiments: salinity, 26-32%; pH, 7 . 3-8 . 4; temperature, 25-30 degree C; dissolved oxygen, 4 . 5-8 . 4 ppm; nitrite, 0 . 36-0 . 99 ppm; and ammonia, 0 . 10-0 . 30 ppm. To each basin were added 50 healthy larvae of specific stages of P. monodon. After an initial acclimation of one hour in the medium, preweighed amounts of the antibiotic were added and thoroughly dissolved. ...
Tiger prawn P.monodon) larvae utilize Brachionus a rotifer, as food in the Zoea 3 and mysis stage... more Tiger prawn P.monodon) larvae utilize Brachionus a rotifer, as food in the Zoea 3 and mysis stages when they change from an herbivorous to an omnivorous diet. The present work aims to show the effects of furanace on the population growth of Brachionus. Cultures of Brachionus were obtained and fed with Chlorella at a density of 1-2x10 SUP-6 cells/ml. Five liters of the culture water were placed in each of 4 white, circular, 152x304 mm plastic basins. The mean initial densities of the rotifer ranged from 26 . 5 to 38 . 5 individuals/ml. The concentrations of furanace were 0, 1, 2 and 3 mg /l. The cultures were vigorously aerated. Population growth was observed after 3, 6, and 9 hours of exposure. The cultures were thoroughly mixed before samples were taken to ensure an almost equal distribution of the rotifers in the water. To facilitate the counting of the rotifer, one drop of Lugol's solution was added to each sample. This immobilizes the rotifer as well as stops further reprodu...
The experimental system put up at SEAFDEC [Southeast Asian Fisheries Development Center; Philippi... more The experimental system put up at SEAFDEC [Southeast Asian Fisheries Development Center; Philippines] consisted of six rectangular (96 x 196 x 42 cm) fiberglass-coated tanks made of marine plywood. It can depurate about 230 to 310 kg bivalves in two days. Initial findings showed that under normal seawater conditions (salinity 29-32 ppt, temperature 27-30 degrees Celsius; oxygen content 3-6.2 mg/L; and pH 7.4-8.3) and moderate rate of flow (7-10 L/min), highly contaminated oysters (MPN 1.0 x 10 to the fifth power to 2.0 x 10 to the sixth power/100 g meat) can be depurated within 48 hr or less. A short flume type of tank with a volume of about 250 L was designed, tested and showed to cleanse oysters under normal conditions in only 24 hr with a flow rate of 7L/min and with very little resulting mortality. More important, the tank can be lifted and moved by only two men of average body built
During a red tide episode caused by Pyrodinium bahamense var. compressa in Western Samar, Philipp... more During a red tide episode caused by Pyrodinium bahamense var. compressa in Western Samar, Philippines in 1983, those who were taken ill after ingesting the green mussel, Perna viridis , resorted to drinking coconut milk (gata , Pilipino) with brown sugar or unpurified sugar lumps (tagapulot , Pilipino) as a temporary palliative, pending medical attention. Many victims felt relief after the drink. Crude toxins (CT) were extracted from P. viridis exposed to Pyrodinium using 0.1 N HCl and reacted with either or both 5% coconut milk (CM) and 5% brown sugar (BS) for an hour. The CT, CM, BS, CT + CM, CT + BS, and CT + CM + BS were assayed in duplicates for saxitoxin using the standard mouse toxicity test. CT with initial toxicity of 2,114 MU/100 g meat was substantially detoxified after a one-hour reaction. In CT + CM, the toxicity was 664 MU/100 g; in combined CT + CM + BS the toxicity was 1,005 MU/100 g. In medium- (436-563 MU/100 g) and low-toxicity extracts (160-231 MU/100 g) no deaths in mice were recorded within one hour of injection
Oysters (Crassostrea iredalei ) from a commercial growing area in Capiz, Iloilo, Philippines, wer... more Oysters (Crassostrea iredalei ) from a commercial growing area in Capiz, Iloilo, Philippines, were purchased from the Iloilo City Central Market and used in a depuration trial within 24 hours of collection. Total coliform (TC) and fecal coliform (FC) levels were determined using the five-tube, most probable number (MPN) technique. Samplings were carried out in three areas in the tank: (a) near the water trickle are, (b) at the middle and (c) near the water outflow area. FC proved to be a better and more consistent indicator of depuration efficiency than TC which gave erratic levels in the first 24 hours. The oysters with initial FC MPN of 2.2 x 10 super(5)/100 g meat depurated to acceptable levels (< 230 MPN/100 g meat) after 48 hours except those in the middle of the tank (490 MPN/100 g). This suggests the presence of an "indifferent" or "dead" spot. Nevertheless, the same oysters depurated successfully within 72 hours. Ranges of chemical and physical parameters in the depuration water were: temperature, 27.0-29.5 degree C; salinity, 30.5-32.0 ppt; and dissolved oxygen, 4.0-6.2 mg/l
This research was undertaken to assess the nursery performance of Avicennia marina and Bruguiera ... more This research was undertaken to assess the nursery performance of Avicennia marina and Bruguiera cylindrica in the difference substrates such as sand, mangrove soil (clay), and the combination of two (sandy clay loam). The study was conducted at NONESCOST Mangrove Civil Reservation Area for 18 weeks. The experiment was arranged in a randomized factorial design (2 x 3) x 5, with two mangrove species, three substrates and five replicates; sand for Treatment I (sand), mangrove soil (clay) for Treatment II, and combinations of the two (sandy clay loam) for Treatment III. There were 10 plants every replicate having a total of 50 plants per treatment. Analysis of variance showed significant difference in survival between Treatments I (82 + 18) and Treatment III (48 + 7) in A. marina ( P 0.05). Survival patterns of A. marina and B. cylindrica showed strong negative correlations with time ( P 0.05) on the growth of A. marina in terms of total height, number of axils, and number of internod...
Paper presented at the 9th Annual Meeting and Scientific Session of the Philippine Society for Mi... more Paper presented at the 9th Annual Meeting and Scientific Session of the Philippine Society for Microbiology held at the Green Room, Philamlife Building, United Nations Ave., Manila, on 5 May 1980.
Detoxification of PYRODINIUM-generated paralytic shellfish poisoning toxin in Perna viridis from ... more Detoxification of PYRODINIUM-generated paralytic shellfish poisoning toxin in Perna viridis from Western Samar, Philippines. ... JavaScript is disabled for your browser. Some features of this site may not work without it. ... Detoxification of PYRODINIUM-generated paralytic ...
The first record of mud lobster Thalassina kelanang (Moh and Chong, 2009) from the Philippines wa... more The first record of mud lobster Thalassina kelanang (Moh and Chong, 2009) from the Philippines was documented in the mangrove forest of Suyac Island, Sagay City, Province of Negros Occidental. The male specimen with a total length of 16.5 cm and 4.5 cm carapace width was found surfacing the mangrove substrate in January 2019. Further survey yielded two more specimens. The specimens had an obtuse rostrum, and a deep median sulcus, which extends posteriorly, nearly the same length but behind the adrostral carinae. The slenderly elongate petasma bears conspicuous spines in the proximal lateral margin. The mounds of T. kelanang with heights ranging from 5 to 15 cm were smaller compared to those of Thalassina anomala. This is the fourth Thalassina species reported from the Philippines.
Abstract Penaeus monodon juveniles (PL 50 ) were fed live and decaying aquatic macrophytes and a ... more Abstract Penaeus monodon juveniles (PL 50 ) were fed live and decaying aquatic macrophytes and a commercial grow-out pellet (40% crude protein) in 80-l glass tanks over a 30-day period. Growth and survival were significantly higher for juveniles fed some form of macrophyte compared to controls (pellets). Survival was highest with live Najas graminea (100%) compared to decaying Ruppia maritima (65.4%), live R. maritima (58.9%) and pellets (52.5%). Juveniles fed decaying N. graminea had the lowest survival rate (30.6%) but the best growth (7.8 mm carapace length (CL), 37.6 mm total length (TL), and 0.2587 g body weight (BW)). The latter body sizes were significantly greater than for juveniles fed pellets (6.2 mm CL, 0.2338 g BW) and other macrophyte treatments. Prawns fed with live R. maritima showed the poorest growth (4.5 mm CL, 24.7 mm TL and 0.1070 g BW). Aquatic plants are directly grazed by penaeid juveniles, or contribute to the detritus fed on by prawns and other benthic organisms. Aside from food, macrophytes also provide cover or shelter from predation and cannibalism.
Zoea 2(Z SUB-2 ) Mysis 1 (M SUB-1 ) and Postlarva 1 (P SUB-1 ) of P. monodon artificially spawned... more Zoea 2(Z SUB-2 ) Mysis 1 (M SUB-1 ) and Postlarva 1 (P SUB-1 ) of P. monodon artificially spawned in closed-system concrete hatchery tanks were bioassayed for their tolerance to the antibiotic furanace. The setup consisted of four 20-liter capacity plastic basins previously conditioned for 15 days with freshwater in full sunlight. During the experiment, each basin was filled with 5 liters of seawater to which was added filtered Chaetoceros and Brachionus to give densities of 5 . 0-7 . 5 x 10 SUP-4 cells/ml and 10-20 individuals/ml, respectively. The following are the properties of the water used throughout the experiments: salinity, 26-32%; pH, 7 . 3-8 . 4; temperature, 25-30 degree C; dissolved oxygen, 4 . 5-8 . 4 ppm; nitrite, 0 . 36-0 . 99 ppm; and ammonia, 0 . 10-0 . 30 ppm. To each basin were added 50 healthy larvae of specific stages of P. monodon. After an initial acclimation of one hour in the medium, preweighed amounts of the antibiotic were added and thoroughly dissolved. ...
Tiger prawn P.monodon) larvae utilize Brachionus a rotifer, as food in the Zoea 3 and mysis stage... more Tiger prawn P.monodon) larvae utilize Brachionus a rotifer, as food in the Zoea 3 and mysis stages when they change from an herbivorous to an omnivorous diet. The present work aims to show the effects of furanace on the population growth of Brachionus. Cultures of Brachionus were obtained and fed with Chlorella at a density of 1-2x10 SUP-6 cells/ml. Five liters of the culture water were placed in each of 4 white, circular, 152x304 mm plastic basins. The mean initial densities of the rotifer ranged from 26 . 5 to 38 . 5 individuals/ml. The concentrations of furanace were 0, 1, 2 and 3 mg /l. The cultures were vigorously aerated. Population growth was observed after 3, 6, and 9 hours of exposure. The cultures were thoroughly mixed before samples were taken to ensure an almost equal distribution of the rotifers in the water. To facilitate the counting of the rotifer, one drop of Lugol's solution was added to each sample. This immobilizes the rotifer as well as stops further reprodu...
The experimental system put up at SEAFDEC [Southeast Asian Fisheries Development Center; Philippi... more The experimental system put up at SEAFDEC [Southeast Asian Fisheries Development Center; Philippines] consisted of six rectangular (96 x 196 x 42 cm) fiberglass-coated tanks made of marine plywood. It can depurate about 230 to 310 kg bivalves in two days. Initial findings showed that under normal seawater conditions (salinity 29-32 ppt, temperature 27-30 degrees Celsius; oxygen content 3-6.2 mg/L; and pH 7.4-8.3) and moderate rate of flow (7-10 L/min), highly contaminated oysters (MPN 1.0 x 10 to the fifth power to 2.0 x 10 to the sixth power/100 g meat) can be depurated within 48 hr or less. A short flume type of tank with a volume of about 250 L was designed, tested and showed to cleanse oysters under normal conditions in only 24 hr with a flow rate of 7L/min and with very little resulting mortality. More important, the tank can be lifted and moved by only two men of average body built
During a red tide episode caused by Pyrodinium bahamense var. compressa in Western Samar, Philipp... more During a red tide episode caused by Pyrodinium bahamense var. compressa in Western Samar, Philippines in 1983, those who were taken ill after ingesting the green mussel, Perna viridis , resorted to drinking coconut milk (gata , Pilipino) with brown sugar or unpurified sugar lumps (tagapulot , Pilipino) as a temporary palliative, pending medical attention. Many victims felt relief after the drink. Crude toxins (CT) were extracted from P. viridis exposed to Pyrodinium using 0.1 N HCl and reacted with either or both 5% coconut milk (CM) and 5% brown sugar (BS) for an hour. The CT, CM, BS, CT + CM, CT + BS, and CT + CM + BS were assayed in duplicates for saxitoxin using the standard mouse toxicity test. CT with initial toxicity of 2,114 MU/100 g meat was substantially detoxified after a one-hour reaction. In CT + CM, the toxicity was 664 MU/100 g; in combined CT + CM + BS the toxicity was 1,005 MU/100 g. In medium- (436-563 MU/100 g) and low-toxicity extracts (160-231 MU/100 g) no deaths in mice were recorded within one hour of injection
Oysters (Crassostrea iredalei ) from a commercial growing area in Capiz, Iloilo, Philippines, wer... more Oysters (Crassostrea iredalei ) from a commercial growing area in Capiz, Iloilo, Philippines, were purchased from the Iloilo City Central Market and used in a depuration trial within 24 hours of collection. Total coliform (TC) and fecal coliform (FC) levels were determined using the five-tube, most probable number (MPN) technique. Samplings were carried out in three areas in the tank: (a) near the water trickle are, (b) at the middle and (c) near the water outflow area. FC proved to be a better and more consistent indicator of depuration efficiency than TC which gave erratic levels in the first 24 hours. The oysters with initial FC MPN of 2.2 x 10 super(5)/100 g meat depurated to acceptable levels (< 230 MPN/100 g meat) after 48 hours except those in the middle of the tank (490 MPN/100 g). This suggests the presence of an "indifferent" or "dead" spot. Nevertheless, the same oysters depurated successfully within 72 hours. Ranges of chemical and physical parameters in the depuration water were: temperature, 27.0-29.5 degree C; salinity, 30.5-32.0 ppt; and dissolved oxygen, 4.0-6.2 mg/l
This research was undertaken to assess the nursery performance of Avicennia marina and Bruguiera ... more This research was undertaken to assess the nursery performance of Avicennia marina and Bruguiera cylindrica in the difference substrates such as sand, mangrove soil (clay), and the combination of two (sandy clay loam). The study was conducted at NONESCOST Mangrove Civil Reservation Area for 18 weeks. The experiment was arranged in a randomized factorial design (2 x 3) x 5, with two mangrove species, three substrates and five replicates; sand for Treatment I (sand), mangrove soil (clay) for Treatment II, and combinations of the two (sandy clay loam) for Treatment III. There were 10 plants every replicate having a total of 50 plants per treatment. Analysis of variance showed significant difference in survival between Treatments I (82 + 18) and Treatment III (48 + 7) in A. marina ( P 0.05). Survival patterns of A. marina and B. cylindrica showed strong negative correlations with time ( P 0.05) on the growth of A. marina in terms of total height, number of axils, and number of internod...
Paper presented at the 9th Annual Meeting and Scientific Session of the Philippine Society for Mi... more Paper presented at the 9th Annual Meeting and Scientific Session of the Philippine Society for Microbiology held at the Green Room, Philamlife Building, United Nations Ave., Manila, on 5 May 1980.
Detoxification of PYRODINIUM-generated paralytic shellfish poisoning toxin in Perna viridis from ... more Detoxification of PYRODINIUM-generated paralytic shellfish poisoning toxin in Perna viridis from Western Samar, Philippines. ... JavaScript is disabled for your browser. Some features of this site may not work without it. ... Detoxification of PYRODINIUM-generated paralytic ...
The first record of mud lobster Thalassina kelanang (Moh and Chong, 2009) from the Philippines wa... more The first record of mud lobster Thalassina kelanang (Moh and Chong, 2009) from the Philippines was documented in the mangrove forest of Suyac Island, Sagay City, Province of Negros Occidental. The male specimen with a total length of 16.5 cm and 4.5 cm carapace width was found surfacing the mangrove substrate in January 2019. Further survey yielded two more specimens. The specimens had an obtuse rostrum, and a deep median sulcus, which extends posteriorly, nearly the same length but behind the adrostral carinae. The slenderly elongate petasma bears conspicuous spines in the proximal lateral margin. The mounds of T. kelanang with heights ranging from 5 to 15 cm were smaller compared to those of Thalassina anomala. This is the fourth Thalassina species reported from the Philippines.
Abstract Penaeus monodon juveniles (PL 50 ) were fed live and decaying aquatic macrophytes and a ... more Abstract Penaeus monodon juveniles (PL 50 ) were fed live and decaying aquatic macrophytes and a commercial grow-out pellet (40% crude protein) in 80-l glass tanks over a 30-day period. Growth and survival were significantly higher for juveniles fed some form of macrophyte compared to controls (pellets). Survival was highest with live Najas graminea (100%) compared to decaying Ruppia maritima (65.4%), live R. maritima (58.9%) and pellets (52.5%). Juveniles fed decaying N. graminea had the lowest survival rate (30.6%) but the best growth (7.8 mm carapace length (CL), 37.6 mm total length (TL), and 0.2587 g body weight (BW)). The latter body sizes were significantly greater than for juveniles fed pellets (6.2 mm CL, 0.2338 g BW) and other macrophyte treatments. Prawns fed with live R. maritima showed the poorest growth (4.5 mm CL, 24.7 mm TL and 0.1070 g BW). Aquatic plants are directly grazed by penaeid juveniles, or contribute to the detritus fed on by prawns and other benthic organisms. Aside from food, macrophytes also provide cover or shelter from predation and cannibalism.
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