Now showing items 1035-1054 of 1075

    • Article

      Use of metaldehyde as a molluscicide in semi-commercial and commercial milkfish ponds 

      RM Coloso, IG Borlongan & RA Blum - Crop Protection, 1998 - Elsevier
      The effect of metaldehyde on brackish water pond snails, Cerithidea cingulata, was tested in 250 m2 ponds, and in semi-commercial and commercial milkfish ponds. The field trials were conducted at three locations, namely Luzon, Visayas, and Mindanao, Philippines. Three application rates (80, 100, 120 kg(ha) of 10% metaldehyde formulation, an untreated control and a reference standard 25% niclosamide EC (1.0 L/ha) were tested during the dry season in a pond with heavy snail infestation. Seven days after application (DAA), snail mortality rates (86-87%) did not differ significantly among the various metaldehyde treatments but were significantly higher than those in the control (6%) and the reference standard (29%). In the field trials, in heavily infested ponds (more than 2000 snails/m2), a dose of 120 kg/ha was effective under both dry and wet conditions. In moderately infested ponds (less than 2000 snails/m2), a dose of 80 kg/ha of a 10% metaldehyde formulation was effective under dry conditions but a dose of up to 120 kg/ha was needed under wet conditions. In a pond dosed with 120 kg/ha of the 10% metaldehyde formulation, the concentration increased in pond water, until 3 DAA relative to the initial level, indicating that the active ingredient had dissolved from the granules. From day 3, the concentration declined steadily to approx. 16% of the initially detected amount at 15 DAA. In the pond sediment, the metaldehyde concentration steadily declined to approx. 1% of the initially detected amount at 15 DAA. As metaldehyde is rapidly degraded in aquatic systems its efficacy in controlling brackish water pond snails depends on a high initial dosage.
    • Article

      Use of ongrown Artemia in nursery culturing of the tiger shrimp 

      P Dhert, RF Bombeo & P Sorgeloos - Aquaculture International, 1993 - Springer Verlag
      Juvenile and adult Artemia produced in a semi flow-through culture system were used as food for postlarval shrimp. The growth performance of shrimp reared on such ongrown Artemia live prey is identical to the growth obtained when feeding newly hatched Artemia. However, a significantly better stress resistance is obtained when the postlarvae are exposed to a low salinity in a stress test. Besides nutritional and energetic advantages, the use of Artemia biomass for feeding postlarval shrimp also results in improved economics as expenses for cysts and weaning diets can be reduced.
    • Article

      The use of potassium permanganate against trichodiniasis on milkfish (Chanos chanos) fingerlings 

      PA Palma, ER Cruz-Lacierda & VL Corre Jr. - Bulletin of the European Association of Fish Pathologists, 2015 - European Association of Fish Pathologists
      Trichodiniasis was noted in an intensive milkfish (Chanos chanos) nursery pond in Dumangas, Iloilo, Philippines. It was predominantly caused by a small trichodinid species (body diameter=23-29 µm) with well-developed denticles, identified as Paratrichodina sp. The trichodinid infection resulted in proliferative changes, including clubbing and epithelial hyperplasis of the gill lamellae sufficient to disrupt respiratory function. Tolerance tests of milkfish fingerlings in an earthen pond-simulated environment resulted in a 24 h TL90 value of 1.98 ± 0.25 ppm KMnO4. A treatment of 1.0 ppm KMnO4 was highly efficacious (96%) in eliminating trichodinids on gills with minimal mortality of treated milkfish observed 24 hours post-treatment.
    • Article

      Use of seaweed meals from Kappaphycus alvarezii and Gracilaria heteroclada as binders in diets for juvenile shrimp Penaeus monodon 

      V Dy Peñaflorida & NV Golez - Aquaculture, 1996 - Elsevier
      Two seaweed meals were tested as binders in shrimp diets. In the first study, Kappaphycus alvarezii or Gracilaria heteroclada in dry ground form were added to an isonitrogenous diet at 3, 5, 7 or 10%. The basal diet had 5% corn starch and 5% wheat flour as binders and served as the control diet. A second study used the seaweed meals at 5, 10 or 15% plus 5% wheat flour and a control diet containing 15% wheat flour (no seaweed meal). These two sets of diets were fed to juvenile tiger shrimp, Penaeus monodon, to assess the acceptability of the seaweed meals in terms of shrimp growth and survival. In both studies, diets with 10% G. heteroclada had the highest water stability after 4 h but differences among diets were minimal. In study 1, shrimp fed diets with 3% and 5% K. alvarezii and 10% G. heteroclada had the highest total biomass and those fed the diet containing 5% K. alvarezii the highest specific growth rate (SGR). Shrimp survival was highest with those fed 3% K. alvarezii and decreased as K. alvarezii was increased. Survival was not affected by the level of G. heteroclada in the diet. Diets with 3% and 5% K. alvarezii had the best feed conversion ratio (FCR). With a modified binder composition in study 2, total biomass and SGR of shrimp fed 10% G. heteroclada did not significantly differ from the control, nor from 10% K. alvarezii and 5% G. heteroclada. Diets with 5% and 10% K. alvarezii or G. heteroclada had the best FCR. Survival was highest among shrimp fed 5% G. heteroclada but was not significantly different from those of the control, 10% G. heteroclada and 10% K. alvarezii groups. Thus, as a supplement for wheat flour, up to 5% K. alvarezii or 10% G. heteroclada meal could be used with no adverse effect on growth. The use of seaweed meals as binder in commercial shrimp diets would minimize organic waste from the feed and would mean an additional market for seaweeds.
    • Article

      Use of the golden apple snail, cassava, and maize as feeds for the tiger shrimp, Penaeus monodon, in ponds 

      I Bombeo-Tuburan, S Fukumoto & EM Rodriguez - Aquaculture, 1995 - Elsevier
      Penaeus monodon stocked in ponds at 8000/ha were fed four types of farm-made feeds starting on day 16 of a 4-month culture period. The feeds were golden apple snail alone or in combination with cooked cassava or maize, or maize only. Mixed feeds resulted in significantly higher production, growth, and better size-frequency distribution of shrimp. Survival (88–99%) was not significantly different among the treatments. Maize alone or snails alone were inadequate. Presumably, the high amount of carbohydrate in cassava (92%) or maize (87%) provided the needed energy, and the high protein content of golden snail (54%) was available for growth. The fatty acid profile of the golden snail shows that it is a good source of 18:2n-6, 18:3n-3, and 20:5n-3 which are essential fatty acids for P. monodon. The golden snail, with an essential amino acid index (EAAI) of 0.84, is a useful alternative source of protein for tiger shrimp. Feeding shrimps with golden snails and cassava yielded the highest net income (P48797/ha-crop) and return on investment (ROI = 206%) better than feeding with maize alone (net income = P23190/ha-crop; ROI = 120%), an industry practice. If shrimp farmers use golden snails as direct feed or as a feed ingredient, the problem of snail infestation in ricefields may be reduced. Snails will no longer be viewed as pests but rather as a resource which has economic value.
    • Article

      Use of thraustochytrid Schizochytrium sp. as source of lipid and fatty acid in a formulated diet for abalone Haliotis asinina (Linnaeus) juveniles 

      MR de la Peña, MB Teruel, JM Oclarit, MJA Amar & EGT Ledesma - Aquaculture International, 2016 - Springer Verlag
      The effects of using thraustochytrid Schizochytrium sp. as source of lipid and fatty acids in a formulated diet on growth, survival, body composition, and salinity tolerance of juvenile donkey’s ear abalone, Haliotis asinina, were investigated. Treatments consisted of diets either containing a 1:1 ratio of cod liver oil (CLO) and soybean oil (SBO) (Diet 1) or thraustochytrid (Diet 2) as source of lipid and fatty acids at 2 % level. Natural diet Gracilariopsis heteroclada (Diet 3) served as the control. No significant difference in growth was observed in abalone fed Diet 3 (SGR: 5.3 % BW day−1; DISL: 265 μm day−1) and Diet 2 (SGR: 5.2 % BW day−1; DISL: 255 μm day−1). Survival ranged from 78 to 85 % for all treatments and was not significantly different from each other. A 96-h salinity stress test showed highest survival of 84 % in abalone fed Diet 2 compared with those fed diets 1 and 3 (42 %). The high growth rate of abalone fed Diet 2 and high tolerance to low salinity could be attributed to its high DHA content (8.9 %), which resulted to its high DHA/EPA ratio of 10.5 %. These fatty acids play a significant role in abalone nutrition. The fatty acid profile of abalone meat is a reflective of the fatty acid profile of the oil sources in the diet. The present study suggests that the use of Schizochytrium oil in lieu of CLO and SBO can support good growth of abalone which is comparable with abalone fed the natural seaweeds diet.
    • Article

      Using local user perceptions to evaluate outcomes of protected area management in the Sagay Marine Reserve, Philippines 

      EL Web, RJ Maliao & SV Siar - Environmental Conservation, 2004 - Cambridge University Press
      Local user perceptions of resource trajectory and indicators of protected area outcomes can be useful in the assessment of integrated conservation projects, both marine and terrestrial. In-depth stakeholder surveys using 12 performance indicators were used to evaluate the perceived outcomes of the Sagay Marine Reserve (SMR), the Philippines. These indicators were a measure of whether the SMR had achieved its management objectives in the recent past and what local stakeholders expected in the future. The respondents contextual situation could be correlated with their perceptions of SMR indicators. There was a generally high level of perceived equity and efficiency of SMR management outcomes, but the sustainability of the SMR, particularly the condition of the fisheries, had been poor over the previous 10 years. Few anticipated an improvement in sustainability indicators over the next 10 years. Respondents from an island village within the SMR had more negative (or less positive) perceptions of SMR outcomes because of their high dependence on the degraded resource, combined with physical and economic isolation. Specific remedies to enhance island villagers satisfaction, such as greater participation, empowerment, alternative economic opportunities and fisheries protection, and replenishment, are necessary. This research serves as an example of how indicators perceived by local resource-accessing stakeholders can and should be main components of both marine and terrestrial protected area assessment.
    • Article

      Utilization of feed and rice straw compost for milkfish, Chanos chanos, production in brackishwater ponds 

      NS Sumagaysay - Journal of Applied Ichthyology, 1991 - Blackwell Publishing
      The study was undertaken to determine the effect of 0, 25, 50 and 75% replacement of organic matter in the feed with rice straw compost on milkfish (Chanos chanos) growth and production. Treatments have similar organic matter and nitrogen loads. Up to 50% substitution (Treatments 1 to 3) was possible without significantly affecting fish growth and yield (668–725 kg/ha). A significant reduction in growth and yield (456 kg/ha) with 75% substitution (Treatment 4) implies that organic matter from compost did not contribute much to fish growth. Low phosphorus content of compost and inadequate phosphorus load in spite of increasing mineral input from compost resulted in similar primary productivity in all treatments. It appeared that compost was not a satisfactory feed substitute and that the fish derived most of their nutrition from the feed. The results further suggest that yield could be economically increased by using a low protein diet (23.8%) given at a lower rate (1.75% of body weight). To further improve yield, feeding rate can be gradually increased as biomass increases, although the most cost-effective ration will depend on the fish capacity to grow under certain environmental conditions.
    • Article

      Utilization of feed pea, Pisum sativum, meal as protein source in practical diets for juvenile shrimp, Penaeus monodon 

      MN Bautista-Teruel, PS Eusebio & TP Welsh - Aquaculture, 2003 - Elsevier
      The potential of feed pea meal as an alternative protein source to soybean meal in practical diets for the juvenile tiger shrimp, Penaeus monodon, was assessed in several experiments. Six isonitrogenous diets were formulated to contain 40% protein. Protein from the feed pea meal replaced 0%, 20%, 40%, 60%, 80%, and 100% of the protein from defatted soybean meal in the diets. These values were equivalent to 0%, 5%, 10%, 15%, 20%, 25%, respectively, of the total protein in the diet. A negative control with no protein sources was added to the treatments. Twelve shrimp post-larvae with an average weight of 0.02±0.01 g were randomly assigned in thirty-five 60-l oval tanks equipped with a flow-through seawater system. The shrimp were fed the formulated diets at a daily feeding rate of 20–25% body weight for 90 days in five replicate samples. No significant differences (P>0.05) were observed in weight gain, feed intake, feed conversion ratio (FCR) and protein efficiency ratio (PER) of shrimp fed diets 0 up to the highest level of replacement. Weight gain of shrimp fed the negative control was, however, significantly lower (P<0.05) compared to the rest of the treatments. Specific growth rates (SGR) of shrimp showed likewise no significant differences among treatments except for the negative control. Survival of shrimp for all treatments ranged between 75% and 100%. The apparent dry matter (ADMD) and protein (APD) digestibilities of the dry feed pea in P. monodon were high at 73.38±4.98 and 92.74±2.62, respectively. Digestibility coefficients for dry matter and protein for the feed pea meal-based diets increased with increasing level of feed pea replacement. There were no significant differences in whole body composition (dry matter, protein, lipid, ash, fiber) of shrimp fed the various diets with feed pea replacement. Pellet water stability was similar for all diets even up to the highest level of replacement. The results have demonstrated that feed pea meal has a very good potential as a substitute protein source up to 100% of the protein from defatted soybean meal, which is equivalent to 25% of the total protein in the diet. An inclusion level of up to 42% in the juvenile shrimp P. monodon practical diet did not manifest any adverse effects on growth, feed intake, FCR, survival, body composition, and digestibility coefficients for dry matter and protein of the shrimp.
    • Article

      Utilization of mung bean, Vigna radiata (Linnaeus) as a novel protein source in practical-type diets for juvenile milkfish, Chanos chanos (Forsskal): Effects on growth, feed efficiency, body composition, and histology of gut and liver 

      MJS Apines-Amar, RM Coloso, MNG Amar, MSM Golez, MGB Bunda & CJ Jaspe - The Israeli Journal of Aquaculture-Bamidgeh, 2015 - Society of Israeli Aquaculture and Marine Biotechnology (SIAMB)
      A 15-week feeding trial was conducted to determine the optimum partial inclusion of mung bean protein in milkfish diet. Six isonitrogenous practical-type diets with mung bean included at 0%, 4%, 8%, 12%, 16%, and 20% of the diet equivalent to 0%, 3%, 7%, 10%, 13%, and 17% of the total dietary protein, respectively, were formulated. Milkfish with average body weight (ABW) of 8.5 ± 0.23g were distributed in eighteen tanks (6 treatments X 3 replications) with 10 fish each. The fish were fed the diets three times daily. Results showed that growth of milkfish was not adversely affected by the inclusion of mung bean protein at any dietary level. Feed conversion ratio (FCR) and protein efficiency ratio (PER) were significantly improved by the inclusion of mung bean at 20% of the diet. Nutrient compositions of the fish carcass were similar in all diets. Furthermore, no detrimental effects attributable to mung bean inclusion were seen in terms of protein retention, hepatosomatic index (HSI), and liver and midgut histology of the fish. Overall, mung bean is a promising protein source for milkfish and can be included up to 20% of the diet contributing as much as 17% of the total dietary protein without detrimental effects on growth, feed performance, PER, protein retention, HSI, and liver and intestinal histology.
    • 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.
    • 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.
    • Article

      Variation of otolith strontium concentration in elongate surgeonfish, Acanthurus mata 

      S Seike, JD Toledo, T Umino & H Nakagawa - Ite Letters on Batteries New Technologies and Medicine, 2005 - Ite-iba Inc.
      The Elongate surgeonfish Acanthurus mata caught from the sea and feeding in the milkfish’s net cages separated from wild fish were measured for their otolith strontium (Sr) concentration using an wave-length dispersive electron probe micro analyzer. The analysis showed three types of Sr distributions in the otolith of wild fish, but the type from artificially fed fish caught in cages was unchanged. The Sr concentration in the otolith could be influence by the water chemistry and/or food composition, and other factors. In conclusion, if you try understand the Elongate surgeonfish life-history based on it’s Sr concentration variation, one should take great care.
    • 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 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.