Now showing items 1-11 of 11

    • Conference paper

      Ability of sandfish (Holothuria scabra) to utilise organic matter in black tiger shrimp ponds 

      S Watanabe, M Kodama, JM Zarate, MJH Lebata-Ramos & MFJ Nievales - In CA Hair, TD Pickering & DJ Mills (Eds.), Asia-Pacific tropical sea cucumber aquaculture. Proceedings of an international symposium held in Noumea, New Caledonia, 15-17 February 2011, 2012 - Australian Centre for International Agricultural Research
      Series: ACIAR Proceedings; No. 136
      Due to frequent viral disease outbreaks, a large proportion of shrimp aquaculture in South-East Asian countries has switched from black tiger shrimp (Penaeus monodon) to P. vannamei, an exotic species originally imported from Latin America. One of the causes of disease outbreaks is thought to be poor water and sediment conditions in the shrimp ponds, which may aggravate disease symptoms. To obtain basic information for co-culture methods of black tiger shrimp and sandfish (Holothuria scabra) for possible mitigation of shrimp-pond eutrophication and prevention of disease outbreaks, basic laboratory experiments were conducted at the Southeast Asian Fisheries Development Center—Aquaculture Department in Iloilo, the Philippines. A feeding trial of juvenile sandfish showed that they do not grow well with fresh shrimp feed on hard substrate. Another trial indicated that sand substrate enhances the growth of juvenile sandfish fed with shrimp feed. A feeding trial using shrimp tank detritus, shrimp faeces and Navicula ramosissima (a benthic diatom) as food sources showed that sandfish grew fastest with the faeces, followed by detritus and N. ramosissima. Dissolved oxygen consumption and acid-volatile sulfur levels in the shrimp tank detritus were reduced by sandfish feeding. This suggests that sandfish are capable of growing with organic matter in shrimp ponds, and can bioremediate shrimp-pond sediment.
    • Article

      Apparent digestibility coefficient of nutrients from shrimp, mussel, diatom and seaweed by juvenile Holothuria scabra Jaeger 

      ZGA Orozco, JG Sumbing, MJH Lebata-Ramos & S Watanabe - Aquaculture Research, 2014 - Wiley
      The ability of Holothuria scabra to digest nutrients, such as organic matter (OM), protein and carbohydrate from animal and plant feed ingredients was investigated. Four test feeds prepared by mixing sand with single ingredients from animal sources (shrimp and mussel) and plant sources (diatom and seaweed) were fed to H. scabra to estimate apparent digestibility coefficient (ADC). The total assimilated nutrient (TAN) increased with ADC, whereas ingestion rate (IR) varied slightly among the feeds suggesting that ADC might be a good indicator of nutrient availability to H. scabra. The ADCOM of shrimp and mussel was significantly higher than that diatom and seaweed: 86.2%, 77.1%, 55.1% and 32.3% respectively. ADCprotein was similar for shrimp (88.7%), mussel (84.8%) and diatom (75.2%), but significantly lower in seaweed (34.4%). ADCcarbohydrate was similar in mussel (58.5%) and diatom (58.3%) as well as in seaweed (31.6) and shrimp (28.0%). ADCprotein was relatively higher than ADCcarbohydrate suggesting that H. scabra generally digests more protein than carbohydrate. Furthermore, results indicated that nutrients from animal-based feeds are more efficiently digested by H. scabra; thus, animal ingredients rich in easily digestible protein could potentially provide an efficiently balanced diet for H. scabra fed with diatom containing high easily digestible carbohydrate.
    • Book chapter

      Co-culture trials of sandfish Holothuria scabra and black tiger shrimp Penaeus monodon in mangroves 

      MJH Lebata-Ramos, EFD Solis, RC Sibonga & S Watanabe - In K Tanaka, S Morioka & S Watanabe (Eds.), Sustainable stock management and development of aquaculture technology suitable for Southeast Asia, 2012 - Japan International Research Center for Agricultural Sciences
      Series: JIRCAS Working Report; No. 75
      To address its mandate to develop environment-friendly culture techniques, the Southeast Asian Fisheries Development Center, Aquaculture Department (SEAFDEC/AQD) is trying to establish a culture system in mangroves for commercially important aquaculture species. Recently, SEAFDEC/AQD has successfully produced sandfish, Holothuria scabra, in the hatchery. Using hatchery-bred juveniles, monoculture and co-culture trials are being conducted in ponds, pens and cages. This study investigated the feasibility of the co-culture of black tiger shrimp, Penaeus monodon, and H. scabra in the mangroves by comparing growth and survival in monoculture and co-culture conditions. Water and sediment quality were compared between treatments. Results showed that growth and survival of P. monodon (P. monodon only = 48.8±4.9%; P. monodon + H. scabra = 46.1±7.4%) and H. scabra (H. scabra only = 13.1±6.1%; P. monodon + H. scabra = 12.3±6.2%) grown together or separately did not significantly differ. P. monodon survivial was positively correlated while growth negatiely correlated with temperature. Feed input significantly increased sulfide levels in both treatments (P. monodon; P. monodon + H. scabra) and sulfide significantly differed between treatments with the highest concentration in P. monodon only, then P. monodon + H. scabra and H. scabra only. Ammonia concentrations followed the same trend as sulfide but did not significantly differ among treatments. P. monodon cultured in mangroves were not affected by the white spot syndrome virus which affected neighboring culture ponds. Results of these initial trials may not be conclusive yet but show a promising culture system for P. monodon that may be integrated with the mangroves.
    • Conference paper

      Development of integrated multi-trophic aquaculture using sea cucumber 

      S Watanabe, M Kodama, JG Sumbing & MJH Lebata-Ramos - In K Gruenthal, M Rust, P Olin & E Trentacoste (Eds.), Genetics in Aquaculture: Proceedings of the 42nd U.S.-Japan Aquaculture Panel Symposium, La Jolla, CA, October 1, 2014, 2017 - United States Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service
      Series: NOAA technical memorandum; NMFS-F/SPO-168
      In Southeast Asian countries, aquaculture production continues to increase. Environmental deterioration associated with water and sediment eutrophication by aquaculture effluent has been problematic, sometimes resulting in disease outbreaks and fish kills due to hypoxia and hydrogen sulfide poisoning. Integrated multi-trophic aquaculture (IMTA) is one of the promising measures for sustainable aquaculture. In this study, a box model estimation of nitrogen (N) budget based on experimental data and values from literature was made for a system of sandfish (Holothuria scabra) in sea cage IMTA with milkfish (Chanos chanos) and Elkhorn sea moss (Kappaphycus alvarezii).

      Information on stocking density, stocking size, mortality, growth, feed ration, feed assimilation, NH4-N production and NH4-N absorption of these species was obtained from a series of experiments and existing literature. In the production system 26 g milkfish were cultured in a 5 x 5 x 4 m cage at the stocking density of 36.7 ind/m3 with the initial feeding ration of 10% of body weight which was gradually decreased to 4% over time; 10 g sandfish were cultured in a cage with the same bottom area as milkfish cage hanged under the milkfish cage to trap particulate N waste (i.e. feces and leftover feed) at the stocking density of 35 ind/m2; the stocking weight of Elkhorn sea moss line culture was 10 kg; culturing period was 200 days.

      It was estimated that milkfish culture cumulatively produced 145 kg of particulate N, and milkfish and sandfish together produced 60 kg of NH4-N in 200 days of culture. Daily assimilation rate of the particulate N by sandfish ranged 3.4 - 12.4%, and 4.3% of the particulate N was estimated to be removed by sandfish in 200 days of culture. Daily absorption rate of NH4-N by Elkhorn sea moss increased exponentially with time and reached 100% after 125 days of culture. Cumulative NH4-N was estimated to be depleted after 162 days of culture. For complete utilization of particulate N by the end of culture, sandfish stocking density should be 805 ind/m2, which is 200 times as high as that in existing sandfish aquaculture operations.
    • Article

      Diet-tissue stable isotopic fractionation of tropical sea cucumber, Holothuria scabra 

      S Watanabe, M Kodama, JG Sumbing & MJH Lebata-Ramos - Japan Agricultural Research Quarterly, 2013 - Japan International Research Center for Agricultural Sciences (JIRCAS)
      To provide a basis for a stable carbon and nitrogen isotope ratio (δ13C / δ15N) analysis to determine the assimilated organic matter in sea cucumber, Holothuria scabra, diet-tissue fractionations were experimentally determined by mono-feeding rearing with diatom. While δ15N fractionation of the whole body wall (2.4‰) was similar to the commonly accepted value (2.6 - 4‰), δ13C fractionation of the body wall (4.2‰) showed considerable discrepancy with the commonly accepted value (0 - 1‰) due to the high content (35% dry wt/wt) of calcareous spicules (CaCO3) in the body wall, which had significantly higher δ13C (-8.6‰) than the organic fractions. Computational elimination of spicules based upon spicule content and spicule δ13C reduced the δ13C fractionation of the body wall to 1.5‰, close to the common value. δ13C fractionation after spicule removal by acid decarbonation and subsequent rinsing (3.2‰) did not agree with the common value, and δ15N fractionation was significantly elevated by decarbonation. δ15N and δ13C fractionations of the intestine (1.5 and 2.2‰, respectively) did not agree with the common values. Since δ13C and δ15N of the feces did not differ significantly from those of the diet, feces may be used to determine ingested organic matter in the wild.
    • Conference paper

      Estimation of energy budget of sea cucumber, Holothuria scabra, in integrated multi-trophic aquaculture 

      S Watanabe, M Kodama, ZGA Orozco, JG Sumbing, SRM Novilla & MJH Lebata-Ramos - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Continuous intensification of aquaculture production has brought about environmental issues associated with eutrophication worldwide. Environmental deterioration such as hypoxia and sulfide production due to water and sediment eutrophication originating from aquaculture effluents have been problematic, resulting to sporadic disease outbreaks and fish kills in the Philippines.

      Integrated multi-trophic aquaculture (IMTA) is one of the promising methods for sustainable aquaculture as it also provides a supplementary source of income to the fish farmers. IMTA is a polyculture system that integrates culturing of fed species (e.g. finfish) the main commodity, organic extractive species (e.g. deposit and filter feeding benthos) and inorganic extractive species (e.g. seaweed). In this study, IMTA techniques were established for small-scale coastal fish farmers in the Philippines, with sea cucumber (Holothuria scabra, commonly known as sandfish), as the key species. Sandfish commands the highest price in tropical sea cucumber species.

      Nitrogen (N) budget of sandfish in polyculture with milkfish (Chanos chanos) and Elkhorn sea moss (Kappaphycus alvarezii), both of which are commonly cultured in the Philippines, was estimated using a simple closed box model.

      Information on stocking density, stocking size, mortality, growth, feed ration, feed assimilation, NH4-N production and NH4-N absorption of these species was obtained from a series of experiments and existing literature. Culture conditions were as follows: 26 g milkfish were cultured in a 5 x 5 x 4 m cage at an average stocking density of 36.7 ind/m3 (i.e. usual practice in the Philippines) with an initial feeding ration of 10% of body weight which was gradually decreased to 4% over time; 10 g sandfish were cultured in a 5 x 5 x 0.3 m cage hung under the milkfish cage to trap particulate N waste (i.e. feces and leftover feed) from milkfish culture at a stocking density of 35 ind/m2; the stocking weight of Elkhorn sea moss line culture was 10 kg. The culture period was 200 days.

      It was estimated that milkfish culture under the above-mentioned schemes cumulatively produced 145 kg of particulate N, and milkfish and sandfish together excreted 60 kg of NH4-N in 200 days of culture. Daily assimilation rate of the particulate N by sandfish ranged from 3.4 to 12.4%, and 6.4% of the particulate N was estimated to be removed by sandfish during the entire 200 days of culture. Daily absorption rate of NH4-N by Elkhorn sea moss increased exponentially with time and reached 100% at 125 days of culture. Cumulative NH4-N from milkfish and sandfish excretion was estimated to be depleted by 162 days of culture.

      For complete utilization of particulate N by sandfish by the end of milkfish culture period (i.e. zero emission), sandfish stocking density should be 805 ind/m2, which is 200 times as high as that in existing sandfish aquaculture operations in countries such as Viet Nam and New Caledonia. The purpose of sandfish culture in IMTA should be emphasized in terms of its economic advantages and not very much on environmental integrity. Cages for sandfish culture should be designed in such a way where only a small fraction of organic matter from milkfish culture (i.e. about 6% in this culture scheme) enters it to avoid sediment quality deterioration and possible death of sandfish. Elkhorn sea moss on the other hand seems very efficient in bioremediation capability.
    • Article

      Growth pattern of the tropical sea cucumber, Holothuria scabra, under captivity 

      S Watanabe, J Sumbing & MJH Lebata-Ramos - Japan Agricultural Research Quarterly, 2014 - Ministry of Tropical Agricultural Research Centre
      The growth of the juvenile sea cucumber, Holothuria scabra, was studied under captivity to elucidate the growth variation pattern and determine the best-fit growth model to estimate age- and size-specific growth rates. Individual growth was extremely variable, with some individuals below the mean initial weight and some expanding their original body length (L) and weight (W) by up to 6.4 and 156 times, respectively; during 84 days of culture starting at 127 days of age. Some of the smallest individuals showed a higher condition factor than larger individuals in the presence of ample food, indicating that lack of food may not be the only impediment to growth. Among the three growth models compared (von Bertalanffy, Gompertz and logistic), the Gompertz model was considered optimal to express H. scabra growth; both in L and W. The age- and size-specific daily growth rate for L and W up to 365 days of age, as estimated by the Gompertz model, had a range of two and nine orders of magnitude in L (0.035 – 0.96 mm/day) and W (3.4 × 10-7 – 3.5 g/day), respectively. Use of the Gompertz model over the linear model, which tends to overestimate growth rates, is encouraged to estimate the growth of H. scabra more accurately.
    • Article

      Metabolic rate characteristics and sediment cleaning potential of the tropical sea cucumber Holothuria scabra 

      M Kodama, JG Sumbing, MJH Lebata-Ramos & S Watanabe - Japan Agricultural Research Quarterly, 2015 - Ministry of Tropical Agricultural Research Centre
      The oxygen consumption rate (OCR) and ammonium excretion rate (AER) of a tropical sea cucumber, Holothuria scabra, were determined in laboratory experiments. OCR and AER exhibited a significant negative correlation to body weight (BW), expressed as a power function of BW: OCR = 0.09 × BW−0.58 (mgO2/g/h, r2=0.89, n=15) and AER = 0.38 × BW−0.19 (μmolN/g/h, r2=0.54, n=15). These values were comparable to those in previous studies on other sea cucumber species. The OCR of shrimp tank sediment was reduced to less than half (4.5 ± 0.3 to 1.0 ± 0.1 mgO2/gdry/h) by the ingestion and excretion process of H. scabra. Acid volatile sulfide (AVS-S) concentration was also decreased to less than half (0.67 to 0.31 mgS/mgdry); despite the low reduction rates of organic carbon and nitrogen contents (0.19 to 0.14 mgC/mgdry and 0.022 to 0.019 mgN/mgdry, respectively). These results suggest that components in the sediment with high oxygen consumption potential were removed by H. scabra. These findings also provide fundamental information with which to evaluate the quantitative role of H. scabra in polyculture with shrimp.
    • Book chapter

      The relationship between nutritional stress and digestive enzyme activities in sea cucumber Holothuria scabra 

      J Zarate, K Niwa & S Watanabe - In K Tanaka, S Morioka & S Watanabe (Eds.), Sustainable stock management and development of aquaculture technology suitable for Southeast Asia, 2012 - Japan International Research Center for Agricultural Sciences
      Series: JIRCAS Working Report; No. 75
      The sea cucumber Holothuria scabra (sandfish) was studied to determine what digestive enzymes are present, to perform a basic characterization of their activity, and to attempt to correlate enzyme activity with nutritional status of the animal. Enzymes alpha amylase, protease (as well as chymotrypsin), cellulase, mannanase, agarase, and xylanase were detected. The enzymes trypsin, alginate lyase and laminarinase were also tested for, but the presence of trypsin was inconclusive, and no alginate lyase or laminarinase was detected. The pH optimum of protease was pH 5 and that of alpha amylase pH 7. Alpha amylase, protease, chymotrypsin, cellulase and mannanase continued to digest their substrates over time. A 2-week starvation experiment showed changes in alpha amylase and protease levels. No differences in cellulase, mannanase, agarose or xylanase activity were detected as a result of the starvation experiment. Another starvation experiment wherein sandfish intestines were sampled every 3 days for 15 days showed that only alpha amylase levels changed with starvation. All samples had lower alpha amylase activity after the withdrawal of feed compared to the day 0 samples. These results suggest the possibility of the use of alpha amylase activity as an indicator of nutritional status, particularly feed deprivation, in sandfish.
    • Article

      Size measurement and nutritional condition evaluation methods in sandfish (Holothuria scabra Jaeger) 

      S Watanabe, JM Zarate, JG Sumbing, MJH Lebata-Ramos & MF Nievales - Aquaculture Research, 2012 - Wiley
      The aims of this study were to establish an accurate size measurement method and a nutritional condition evaluation method of Holothuria scabra (Jaeger). Although 0.5% KCl and 0.05% MgSO4 did not induce anaesthesia, 2% menthol–ethanol for 20 min was found to be effective and harmless. The anaesthetization significantly reduced the coefficient of variation of the mean body length and weight by 68% and 43% respectively. During starvation, body size and weight decreased concomitantly, resulting in an unchanged condition factor (body weight/volume), suggesting that the condition factor cannot be used as an index of nutritional condition. Protein, cholesterol and carbohydrate concentrations in the body fluid were analysed to study the relationship with starvation. As the protein and cholesterol concentrations initially increased and then decreased during the starvation period, it is difficult to use them as an index of nutritional condition. The carbohydrate concentration showed a gradual one-fold increase during 10 days of starvation, and it may be used as a proxy for nutritional condition; however, further physiological studies are needed. Body fluid density and volume relative to body size gradually increased and decreased, respectively, during starvation. These methods may be used to correctly monitor the conditions of H. scabra in studies for aquaculture and stock enhancement techniques.
    • Book chapter

      Utilization of organic waste from black tiger shrimp, Penaeus monodon, by sandfish, Holothuria scabra 

      S Watanabe, JM Zarate, MJH Lebata-Ramos, MFJ Nievales & M Kodama - In K Tanaka, S Morioka & S Watanabe (Eds.), Sustainable stock management and development of aquaculture technology suitable for Southeast Asia, 2012 - Japan International Research Center for Agricultural Sciences
      Series: JIRCAS Working Report; No. 75
      In Southeast Asian countries, a large proportion of shrimp aquaculture has switched its target species from native black tiger shrimp, Penaeus monodon, to exotic P. vannamei because of frequent viral disease outbreaks. One of the causes of disease outbreaks is thought to be poor water and sediment conditions in the shrimp pond, which aggravate disease symptoms. To establish co-culture methods of black tiger shrimp and sandfish, Holothuria scabra, for possible mitigation of shrimp pond eutrophication and prevention of disease outbreaks, laboratory experiments were conducted at the Aquaculture Department, Southeast Asian Fisheries Development Center (SEAFDEC/AQD) in Iloilo, Philippines. A feeding trial of juvenile H. scabra using benthic diatom, Navicula ramossisima, and powdered P. monodon feed showed that H. scabra do not grow with fresh shrimp feed on a hard substrate. A feeding trial with and without sand substrate with shrimp feed as food showed that the substrates enhance the growth of H. scabra. H. scabra juveniles were found to grow with detritus and P. monodon feces as food sources in tanks. It was also shown that addition of ground oyster shell to the sand substrate enhances the growth of H. scabra when fed with N. ramossisima. Thus, these results suggest that H. scabra can grow by feeding on organic matter present in a P. monodon pond and may be used to mitigate organic load in P. monodon ponds.