Project Technical Report:" Development of clam culture for improvement and diversification of livelihoods of the poor coastal communities in Central Vietnam - MS4 " potx
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Ministry of Agriculture & Rural Development Collaboration for Agriculture & Rural Development (CARD) 027/05VIE DevelopmentofclamcultureforimprovementanddiversificationoflivelihoodsofthepoorcoastalcommunitiesinCentralVietnam MS04: 3 rd Six-Monthly Report April – October, 2007 1 Table of Contents 1. Institute Information 3 2. Project Abstract 4 3. Executive Summary 4 4. Introduction & Background 6 5. Progress to Date 6 5.1 Implementation Highlights 6 5.1.1 Clam production (Grow-out trials) 6 5.1.2 Hatchery production 8 5.1.3 Propagation ofthe technologies (on farm trials level) 16 5.2 Smallholder Benefits 16 5.2.1 Opportunity to utilize the brackish water ponds forclam production 16 5.2.2 Increasing in production and benefit from clamcultureinthe intertidal areas 16 5.2.3 Easily Applicable Farming Knowledge 16 5.2.4 Low Investment Risk 16 5.2.5 Maximizing Commercial Potential through Knowledge 16 5.3 Capacity Building 17 5.3.1 ARSINC 17 5.3.2 End-users 18 5.3.3 Enhanced reputation and relation ship with other institutions and collaborators 18 5.4 Publicity 18 5.5 Project Management 18 6. Report on Cross-Cutting Issues 18 6.1 Environment 18 6.2 Gender and Social Issues 19 7. Implementation & Sustainability Issues 19 7.1 Issues and Constraints 19 7.2 Options 19 7.3 Sustainability 19 8. Next Critical Steps 19 9. Conclusion 19 10. Statuatory Declaration 20 2 1. Institute Information Project Name DevelopmentofclamcultureforimprovementanddiversificationoflivelihoodsofthepoorcoastalcommunitiesinCentral Vietnam. (Project No: 027/05VIE) Vietnamese Institution Aquaculture Research Sub-Institution for North Central (ARSINC) Vietnamese Project Team Leader Mr. Nhu Van Can (Project Director) Mr. Chu Chi Thiet (Project Manager) Australian Organisation South Australian Research andDevelopment Institution (SARDI) Australian Personnel Dr Martin S Kumar (Team Leader) Dr Bennan Chen (Senior Scientist) Date commenced February 2006 Completion date (original) February 2009 Completion date (revised) Reporting period November 2006, April 2007 Contact Officer(s) In Australia: Team Leader Name: Dr Martin Kumar Telephone: 08 82075 400 Position: Principal Scientist, and Program Leader, Integrated Biosystems Integrated Resource Management and Biotechnology Fax: 08 82075481 Organisation South Australian Research andDevelopment Institution (SARDI) Email: kumar.martin@saug ov.sa.gov.au In Australia: Administrative contact Name: Telephone: Position: Fax: Organisation Email: InVietnam Name: Nhu Van Can Telephone: +84.383829884 Position: Director Fax: +84.383829378 Organisation Aquaculture Research Institute for North-Central Email: arsinc@vnn.vn 3 2. Project Abstract 3. Executive Summary The. • The stocking biomass of 2 ton/ha is recommended for optimising cost benefits inclam production under intertidal culture conditions. • Successful production ofclam as a rotational crop in prawn farms provides new opportunity forthe farmers to utilise the prawn farm which normally used only for 4 months per year for shrimp culture. • Artificial conditioning ofclam brood stock has been successfully completed • The mass production of 2 million spat was achieved under revised larval rearing procedure developed. The main objective oftheproject is to develop and extend theclamculture technology (hatchery and husbandry) to sustain livelihoodsofpoorcoastal farmers inthe North Central provinces and to develop a strategy which contributes to sustainable aquatic environment management using clam aquaculture to improve prawn farm effluent utilisation. Inthe first half ofthe second year, two types ofclam production trials (intertidal clam production, clam production in prawn ponds as rotational crop) and broodstock conditioning trials have been successfully completed. Details ofthe both production trials along with brood stock conditioning results are included in this report. Key findings are listed below. 4 3.1 Project Implementation Progress 3. 1.1 Key Highlights Project progressed well during the last 18 months and achieved specified milestones related to the technology developmentinclam husbandry (production) and hatchery areas. Following milestone reports submitted were reviewed and accepted. • Socio-economic evaluation report • 1 st six monthly report • 2 nd six monthly report Inthe first half ofthe second year, two clam production trials including; intertidal clam production, clam production in prawn ponds as rotational crop, broodstock conditioning have been successfully completed. Details ofthe both production trials along with brood stock conditioning results are included in this report. A farmer selection criterion was developed in consultation with lead farmers, village representatives and provincial authorities. The details will be reported inthe next 4 th six monthly report. Inthe second year, the work will be concentrated on farm trials, which fine tune the technology and facilitate formulation of extension manuals. Inthe third year, work will focus on extension of technology including expanded farmer participated trials. Project impact will also be assessed during the third year 3.1.2 Key outcome a) Production experiments made excellent progress • Optimisation parameters for intertidal clam production have been determined. The stocking biomass of 2 ton/ha is recommended for optimising cost benefits inclam production under intertidal culture conditions. • Viability ofclam production in prawn pond as a rotational crop has been established. Successful production ofclam as a rotational crop in prawn farms provides new opportunity forthe farmers to utilise the prawn farm which normally used only for 4 months per year for shrimp culture. b) Hatchery production experiments. Based on the results of initial larval rearing experiments, a second mass spat production trials successfully completed by producing 2 million spats. Artificial conditioning ofclam brood stock has been successfully completed Experimental design on larval rearing and nursery production has been revised based on this trial results. Larval rearing and brood stock conditioning experiments are in progress. c) On farm trials/Demonstration. An introductory workshop on clamculture has been conducted forthe farmers inthe North Central Provinces. Farmer selection criteria for demonstration were prepared. Lead farmers were selected. Trials are under way. Further workshops are being organised to provide guidelines on demonstration trials to farmers. Overall theproject is progressing well as per the proposal. 5 4. Introduction & Background The main objective is to develop and extend theclamculture technology (hatchery and husbandry) to sustain livelihoodsofpoorcoastal farmers inthe North Central provinces; and to develop a strategy which contributes to sustainable aquatic environment management using clam aquaculture to improve prawn farm effluent utilisation. The aims ofthe proposed project are: a) to provide poor fisher community an alternative income, food security; b) to improve technological and extension capacity forthe stakeholders; and c) to reduce negative impacts of shrimp culture through implementation of a strategy for environmental management and waste utilisation of existing resources. 4.1. Specific objectives: The objectives of this project (027/05VIE) include the following: • to develop and extend theclamculture technology (hatchery and husbandry); • to sustain livelihoodsofpoorcoastal farmers inthe North Central provinces; and • to develop a strategy which contributes to sustainable aquatic environment management using clam aquaculture to improve prawn farm effluent utilization. 4.2. Outputs Expected In accordance with expected output proposed, the last six months were focused on following aspects related on the following - Completed intertidal clam production trial - Completed rotational clamin prawn farm - One set of mass production trials completed, Larval rearing experiments to optimize the larval survival and growth is in progress. - Brooder conditioning experiments completed - Farmer selection criteria for demonstration was developed 4.3. Methodology The visits by Australian Project Leader in April 2007 enabled to undertake major review ofthe results obtained on clam production and larval rearing trials and also enabled to fine tune the experimental procedure for larval rearing and nursery production optimization. Team workshop was organised in April enable to evaluate theclam production results and larval rearing methods. Larval rearing and nursery productions experiments were revised andthe trials are in progress. Demonstration trials, design, planning, farmer selection criteria and execution procedures were finalised. 5. Progress to Date 5.1 Implementation Highlights 5.1.1 Clam production (Grow-out trials) The research in pond culture type will be focused on suitability of substrate, optimum stocking density, and stocking size. All experiments were conducted in triplicate. The outcome ofthe experiments (culture types) will be used forthedevelopmentoftechnical 6 guidelines for on farm trials inthe second year. Theclam production involved the following 5 types culture trials: a) Clamculture using prawn farm influent water (reservoir): Clamculture was carried out as a pre- treatment for water intake in prawn farm. Work completed andthe results reported b) Clamculture using prawn farm effluent (effluent treatment pond). Clamculture was conducted by utilising prawn farm effluent. Work completed andthe results reported. c) Shrimp andclam polyculture: Simultaneous cultureof prawn and clams was undertaken with a view to improve farm water quality as well as generate additional income. Work completed andthe results reported. d) Alternative/rotation crop: Clamculture was under taken after the pawn harvest as rotational crop. Work completed and results included in this report. e) Clamculturein intertidal area: Inter tidal area was used forclam culture. Work completed andthe results included in this report. 5.1.1.1 Experiment on clamcultured inthe intertidal areas Traditional clamculture has been undertaken inthe inter-tidal areas. The aim of this experiment was to enhance the profitability ofclam farmer. The key objective was to increase productivity and benefit by determining the optimum stocking density and stocking size. The other parameters within theculture system can not be altered as it is a natural ecosystem highly connected to capture fisheries which is one ofthe key industry forthe fisher community. Materials and method The inter-tidal clamculture experiment was undertaken in 24 plots of 50 m 2 each for 8 treatments (3 replicates each). The small size ofclam seed (1.0 cm) were stocked at 4 different stocking biomass 0.5, 1.0, 2.0 and 3.0 tons/ha and referred as T1, T2, T3 and T4 respectively. The bigger size ofclam seed (1.7 cm) were stocked at 4 different stocking biomass of 3.4, 6.8, 13.6 and 20.6 ton/ha and referred as T5, T6, T7 and T8 respectively (the densities were adjusted due to actual stocking size availability). Experiment was terminated after 165 days rearing. The environment factors such as temperature, DO, pH and turbidity , salinity of water inthe experiment site were monitored daily at 3 designated points within the experimental area while samples of water were analysed weekly for Total N, Total P, Ammonia and Nitrate. Growth of clam, expressed in mean of height (cm) and mean of weight (gr), was determined by random sampling (n=30) and measured every fortnight. The daily specific growth rate (SGR) was calculated using the following formula: SGR(%/day) = 100*(LnW f -LnW i )/t Where: W i and W f are mean of initial weight and final weight, respectively and t is number of experiment days. The final production (expressed as ton/ha) of each treatment was conducted by entirely harvested andthe biomass gained was calculated from final production minus the stocking biomass. Size variation was evaluated according to (Wang et al., 1998) in which the mean of three replicates ofthe coefficient of variation (CV) was used to examine the inter-individual 7 weight variation among theclamin each treatment: CV(%)=100*SD/ M where M is mean of weight and SD is standard deviation oftheclamin each treatment. The meat ratio (% of meat weight/ total weight) ofclam estimated to understand meat yield. This parameter was measured by random sampling ofclamandthe total weight oftheclamand meat weight was measured by separating the meat content. The excess water was removed by putting the sample on tissue papers. The fatty acids content ofclam was determined from random samples, preserved in Liquid Nitrogen Biological Container (YDS-3, -196 o C). The samples then were analysed by extracting the fatty acid in methanol/toluene mixture (3:2 v/v) and analysed in Finnigan Trace GC untra, capilary collume BP-70 (50m x 0.32mm x 0.25µm) inthe Laboratory of Vienamese Academy of Science and Technology. All data ofthe treatments were tested for significant differences (p<0.05 or p<0.01) using One-way ANOVA followed by Turky test for multiple comparisons of means. The data are expressed as Average ± SD and statistical analyzed was performed using GraphPad Prism version 4.0 and Microsoft Office EXCEL for Window. Results and discussions 1.1 The environment conditions ofthe experiments The experimental site inthe intertidal area is situated in Hau Loc District, Thanh Hoa Province near the estuary where clam naturally occurred. The environment conditions such as DO, water temperature, pH and salinity (table 1) are regarded as the best conditions forclam development. The high levels of salinity fluctuation are typical for estuary ecological conditions. This means clam are not be affected by the marked variation inthe salinity and good growth and survival rate noticed. The average water temperature was 23.59±2.40 o C s. Table 1. Environment conditions inthe cultured areas Paramenters DO (ppm) Water temperature ( o C) pH Salinity (ppt) Turbidity (cm) Aver 6.25±0.42 23.59±2.40 25.65±2.84 9.05±3.13 Max 7.66 31.00 8.99 31.00 20.00 Min 5.50 19.50 7.21 20.00 5.00 1.2 Growth performance The growth performance ofthe two stocking sizes ofclam at different stocking biomass expressed in specific growth rate, final length and final weight are shown inthe table 2 and table 3. Table 2. Growth performance ofclam at stocking size of 1.0cm Treatments T1 T2 T3 T4 SGR 1.25±0.05 a 1.13±0.05 a 1.08±0.10 ab 0.94±0.37 b Final length (cm) 2.04±0.13 a 2.01±0.09 ab 1.95±0.10 b 1.95±0.11 b Final weight (gr) 5.92±1.08 a 5.76±0.81 ab 5.46±0.76 ab 5.30±0.85 b % of meat/total weight 15.87±1.00 a 15.48±2.72 a 15.53±1.02 a 15.15±5.47 a CV% (weight) 28.72±2.55 a 23.07±0.24 b 23.73±1.55 b 27.78±2.11 ab Value (Mean±SD) followed by different superscript letters within a row are significantly different (P<0.05). T1, T2, T3, T4 are treatments ofclam cultured at 0.5, 1.0, 2.0 and 3.0 tons/ha respectively. SGR = daily specific growth rate; CV = coeficient of variation 8 9 Forthe small size ofclam (1.0cm), there was no significant difference in specific growth rate among T1, T2 and T3 treatments (table 2) indicating that growth oftheclam was not be affected by the stocking biomass below 2 tons/ha. The final size ofclam was more variable at low (T1) and high (T4) levels of stocking density compared to the medium ones. The meat yield expressed in percentage of meat per total weight, which regarded as the most valuable part ofclam was not significant different (p>0.05) in all treatments. Table 3. Growth performance ofclam at stocking size of 1.7cm Treatments T5 T6 T7 T8 SGR 0.62±0.04 a 0.46±0.03 b 0.33±0.02 c 0.32±0.02 cd Final length (mm) 2.36±0.17 ab 2.40±0.10 a 2.32±0.11 bc 2.27±0.10 c Final weight (gr) 9.24±1.20 a 9.33±0.95 a 8.90±1.12 a 8.21±1.01 b % of meat/total weight 14.53±1.89 a 15.78±2.35 a 16.53±0.62 a 15.48±1.31 a CV% (weight) 22.3±0.45 a 19.05±5.16 a 18.69±3.36 a 22.73±4.16 a Value (Mean±SD) followed by different superscript letters within a row are significantly different (P<0.05). T5, T6, T7 and T8 are treatments ofclam cultured at 3.4, 6.8, 13.6 and 20.6 ton/ha respectively. SGR = daily specific growth rate; CV = coeficient of variation The growth performances of 1.7 cm clam stocked at different densities are provided in table 3. Inthe case of 1.7 cm clams, the increase in stocking biomass significantly impacted specific growth rate. At the stocking density higher than 3 tonnes/hectre, the SGR was relatively low and was not significantly different for T7 and T8 treatments. The final length and final weight ofthe T8 treatment were significantly smaller than the other treatments. Generally, at younger stage, animal grow at a faster rate. Inthe case of clam, the small size (1 cm) the growth was significantly better than the bigger size (1.7cm) if stocked at same biomass. Inthe intertidal areas, the natural feed and environmental factors are uncontrollable and are dependent of nature. Dynamics of tide, wave and current create the availability of algae, organic matter that regarded as feed for clam. However, clam is a filter feeder and passively dwells on the bottom therefore, increase in biomass beyond certain level, the natural feed might not be enough for growing. Results of growing performance (table 3) indicated that at high stocking biomass (3 ton/ha), the growing could be inhibited as it was evidenced that the grow rate was significantly reduced as in creasing of stocking biomass. It also is noted that theculture period is winter time ofthe year when water temperature normally is low and not appropriate for growing of M. lyrata, the tropical species. 1.3 Survival The stocking biomass impacted the survival rate in both sizes of clams stocked. Survival was very high inthe low stocking biomass and was almost similar inthe treatment T2 and T3. The survival rate in T1 and T4 treatment was significant different (P<0.05). Inthe bigger size groups, the T7 and T8 treatments resulted in very low survival and not significant different compared to the treatment T5 and T6. The environmental condition and food availability could be attributed as main reason forthe impact stocking biomass on survival rate. T1 T2 T3 T4 50 60 70 80 90 100 110 a ab ab b Clam at stocking size of 1.0 cm Survival (%) T5 T6 T7 T8 50 60 70 80 90 100 110 a b c c Clam at stocking size of 1.7 cm Survival (%) Fig 1. Survival ofclam size 1.0cm and 1.7cm rearing at different stocking biomass. Valu , T3 1.4 Production and quality ated from both growth and survival. There was a positive T3 T4 e (Average ± S.D) followed by different superscript letters are significantly different (P<0.05). T1, T2 and T4 are treatments ofclam cultured at 0.5, 1.0, 2.0 and 3.0 tons/ha respectively; T5, T6, T7 and T8 are treatments ofclam size 1.7cm cultured at 3.4, 6.8, 13.6 and 20.6 ton/ha respectively. The production ofclam was estim relation noted on clam production and stocking biomass although the growth and survival were negatively affected. Among the small stocking size group, the final production increased accordingly with the increase stocking biomass and no significant difference (P>0.05) was detected between T1 and T2 nor T3 and T4. However, T1&T2 were significantly different in final production compared to T2 & T3. The percentage of biomass gained, in contrast, was showing reduction trend when increasing the stocking biomass and no significant difference between T1 and T4 was detected. This is due the fact that the increase in biomass negatively affected the growth and survival ofthe clams. Table 4. Biomass production ofclam at stocking size of 1.0cm Treatments T1 T2 Final production (ton/ha) 4.14±0.57 a 6.82±0.56 a 12.62±2.16 b 14.84±0.91 b Biomass gained (ton/ha) 3.62±0.57 a 5.78±0.56 a 10.54±2.16 b 11.72±0.91 b % of biomass gained 6 5 5 97.1±109.4 a 55.8±53.6 ab 06.9±104.0 ab 375.8±29.3 b Value (Mean±SD) followed by differen letters with fferen were significantly mass production ofclam at stocking size of 1.7cm T7 T8 t superscript in a row are significantly di t (P<0.05). T1, T2, T3 and T4 are treatments ofclam cultured at 0.5, 1.0, 2.0 and 3.0 tons/ha respectively Inthe bigger stocking size (1.7cm), the final production inthe treatments increased as increase in stocking biomass (p<0.05) while the biomass gained was not significant different (p>0.05) inthe treatment T5 and T6. The percentage of biomass gained, in contrast, was reduced as increasing of stocking biomass in T5, T6 and T7. However, the treatments T7 and T8 were not significantly different in terms biomass gained during the experimental period. In both sizes the increase in biomass certainly impacted net production negatively. Table 5. Bio Treatments T5 T6 Final production (ton/ha) 9.49±0.68 a 14.46±0.69 b 23.58±0.68 c 34.80±1.00 d Biomass gained (ton/ha) 6.10±0.68 a 7.68±0.69 a 10.02±0.69 b 14.46±0.99 c % of biomass gained 180.0±20.0 a 113.3±10.1 b 73.9±5.1 c 71.1±4.8 c 1 [...]... availability in ponds was not the factor that limited theclam quality The presence of the number of fatty acids detected in this clam compared to those intheclam cultured inthe intertidal area indicated that clam cultured in pond were not different in terms of quality as food for human consumption Table 12 Fatty acids ofclam cultured at different stocking sizes and different stocking biomass inthe rotational... Clam aquaculture in Vietnam, is a family or household activity Women undertake 5 0-6 0% ofthe work including husbandry, harvesting and marketing Therefore, aquaculture activities are very much a household duty If the proposed project is properly implemented through making relevant information more available and improving the skills ofthe information deliverers, the results will significantly increase... Feeding frequency was 4 times in 24 hours (6h, 11h, 16h, 21h) -The salinity was maintained at 25ppt during conditioning period, the bottoms of tanks were provided with sandy substrate B Spawning method -The matured brooders were transferred to spawning tank forthe spawning The male and female were kept together inthe same spawning tank (200 lit) with density at 150 clams per 200 litter tanks - The. .. T3 and T4 are treatments ofclam cultured at 0.5, 1.0, 2.0 and 3.0 tons/ha respectively TheThe main cost inclamculture is the expenditure in seed purchase Cost of seed ranged between 46% to 81% in small size seed (1cm) forthe four treatments ( T1, T2 T3 &T4) As all other costs are fixed the increase in stocking biomass increased the cost Although total production increased with the increase in. .. utilisation/treatment and simultaneous production of clams Developed method for prawn farm influent pre-treatment and simultaneous production of clams Developed clamculture technique inthe intertidal area Performance Indicator Appropriate stocking size and density determined Suitable stocking size, density and substrate determined for each culture types Means of Verification At least each province and each culture. .. hatchery technical procedure and management • Training of two ASINC technicians o Live feed o Data processing and management Clamcultureinthe inter-tidal area Prawn andClam (poly culture Effluent + clamculture Reservoir culture Hatchery manual prepared Training conducted Manual submitted Implementing Report submitted Developmentof skilled human resources Developmentof skilled human resources Development. .. cultured inthe intertidal areas is showed inthe table 6 and table 7 The net profit estimated based on the output cost and input cost and value/price ofclam 3 Table 6 Economical evaluation ofclam rearing at stocking size of 1.0cm Treatments Input Seed cost (35.000 VND/kg) Mesh and fencing (VND/ha) Labour cost for protection, cleaning (6monthsx1.200.000 VND/m) Hut for daily monitoring (VND/hut) Land lease... contribution in terms of income and food and therefore their importance and self esteem The Technological and socioeconomic study conducted by project team indicated that farmers received low prices forclam due to exploitation by middle men Cooperatives need to play a major role in marketing the clams Study further confirmed that shrimp andclamculture systems are seen as the backbone of the coastal community... personnel inputs have been delivered andthe equipment and services identified above provided has been handed over to the Lead Vietnamese Institution Separate sheet attached 22 23 APPENDIX A -Project Progress against Proposed Objectives, Outputs, Activities and Inputs Project Title: Vietnamese Implementing Institution: Development of clam cultureforimprovementanddiversificationof Aquaculture Research... variation among theclamin each treatment: CV(%)=100*SD/ M where M is mean of weight and SD is standard deviation of the clam in each treatment The meat ratio (% of meat weight/ total weight) ofclamin this experiment was evaluated to determine meat yield The total weight andthe weight of meat (separating the meat from the shell) measured from the randomly selected samples All data of the treatments . 2 1. Institute Information Project Name Development of clam culture for improvement and diversification of livelihoods of the poor coastal communities in Central Vietnam. (Project No:. (027/05VIE) include the following: • to develop and extend the clam culture technology (hatchery and husbandry); • to sustain livelihoods of poor coastal farmers in the North Central provinces; and. the difference in the ammonia level in the ponds of the two treatments. Survival and grow performance of the clam Table 11. Survival and growth performance of clam in the rotational pond cultures