PROJECT DOCUMENT INTRODUCTION

Transcription

1 Fortieth Meeting of the Program Committee Southeast Asian Fisheries Development Center Centara Grand Hotel at Central Plaza Ladprao, Bangkok, Thailand November 2017 WP03.2a-ii PROJECT DOCUMENT Program Categories: Departmental Programs Project Title: Healthy and Wholesome Aquaculture Responsible Department: SEAFDEC/AQD Total Duration: Funding Sources: Philippine Government Estimated Budget for 2018: USD 525,204 INTRODUCTION The development of aquaculture feed with less dependence on fish meal and fish oil, as well as the advancement of aquatic health management are the thrusts of this program towards a healthy and wholesome aquaculture. Feed formulations for important aquaculture species in the region have been sought out, characterized and biologically tested in aquaculture laboratories. Although inclusion levels of fish oil and fish meal can be reduced without affecting the growth performance of cultured species, the increasing volume of feed produced for the industry has led to the increase of their usage in aquaculture. Replacing these commodities in aquaculture feed is recognized as an international research priority towards a sustainable increase in fish production. Further, innovations on fish health management are necessary in face of devastating losses due to various aquatic diseases. New approaches to disease management, including the use of probiotics, alternative safe drugs/chemicals and natural products to replace harmful drugs which have raised concerns for safety and quality. The preservation of the environmental quality of aquaculture sites is likewise necessary. PROJECT Goal/Overall Objectives Contribute to improvement of aquaculture production through innovations in nutrition, feeding, fish health management, and in preserving the environmental integrity of aquaculture. The specific objectives are to: Find effective alternative protein sources to fish meal in dietary formulations Determine specific nutrients that enhances growth performance Promote practices and strategies in nutrition to improve production Investigate the efficacy of probiotics and rationalize the need and application of diagnostics that will ensure biosecurity within culture systems and keep out exotic pathogens, especially trans-boundary pathogens Promote the wider use of conventional diagnostic as well as new methods especially for newly reported, emerging diseases Find effective alternative safe drugs/chemicals (including natural products) to manage aquaculture diseases in lieu of harmful chemicals and drugs whose use has been discouraged or banned due to quality and safety issues Outcomes and Expected Outputs Alternative protein sources identified for the larval diet of tilapia (Oreochromis niloticus) and grouper fingerlings (Epinephelus coioides), and lipid source for the abalone (Haliotis asinina) 1

2 Development of adequate formulations for the Asian seabass (Lates calcarifer) by determination of three essential amino acids required for growth Protocols and strategies to increase production of Penaeus indicus, soft-shell Scylla serrata and two other Scylla species promoted The application of probiotic Bacillus species in larval rearing of Penaeus established Economics of producing Scylla serrata juveniles for soft-shell crab farming identified Project Description/Framework Activity 1: Find effective alternative protein sources to fish meal and fish oil in dietary formulations Milkfish by-product is protein rich with high potential as a feed ingredient. Processing this into a hydrolysate using an enzyme could improve its utilization. Milkfish by-product is processed into hydrolysate and evaluated as a feed ingredient in the diet of the freshwater finfish larvae of tilapia (Oreochromis niloticus). The effect on larval enzyme development is assessed. Copra meal is about 21% protein. Increasing the level of protein in this ingredient would make this a valuable replacement for fish meal. Protein-enhanced copra meal (PECM) is a potential alternative protein source in diets of high value species such as grouper, (Epinephelus coioides). This product is analyzed for nutrient profile and included in different levels in grouper diet. The optimum inclusion level of PECM, its nutrient digestibility and the effect on liver and distal intestine morphology of grouper are assessed. The abalone, Haliotis asinina, is a high value commodity in the export market and this species readily accepts formulated diet. Lipid source is considered important in the diet of abalone breeders. The algae, thraustochytrid, has a good profile of fatty acids and would be a good alternative source for fish oil in the abalone diet. The optimum amount of thraustochytrid in the abalone breeder diet will be determined and the resulting reproductive performance assessed. Activity 2: Determine specific nutrients that enhances growth performance The Asian seabass is a popular food fish in the region. The commercial feed for this species is not specifically formulated and feed for other high value species such as snapper and grouper feed are used instead. An efficient feed for sea bass can be formulated by inclusion of essential amino acids at required levels. This activity would determine the three amino acids required by seabass namely, leucine, isoleucine and histidine. Amino acid test diets will be prepared for seabass and requirement levels will be based on growth data and biochemical parameters. Activity 3: Promote practices and strategies in nutrition to improve production P. indicus has a potential as a crustacean species for culture in the Philippines. A study on hatchery production and semi-intensive pond culture of this species are conducted. Breeders from the wild are collected to produce postlarvae in the hatchery so that these can be grown and finally produce hatchery-bred breeders. The response of hatchery-bred postlarvae fed two commercial diets are assessed in a pond feeding experiment to demonstrate profitability of a semi-intensive pond culture of this species. Soft-shell crab production is established in some countries in the region, however, the source of the mangrove crab is from the wild and may not be sustainable in the future. DOST funded a project on soft-shell crab production with crabs sourced from hatchery. A soft-shell crab production in a commercial scale model farm is being established for dissemination to stakeholders through training and collaboration. Crabs like other crustaceans need to molt to grow and that molting is not 2

3 simultaneous. A study on spinach leaves extract is conducted in the laboratory with the aim to induce crab to molt. The extract is a natural source of phytoecdysteroids that could induce molting. Activity 4: Testing the efficacy of indigenous probiotics The protective effects of Bacillus sp. JL47 containing different levels of amorphous Poly-βhydroxybutyrate (PHB) was examined using gnotobiotic Artemia. The effects of PHB-accumulating Bacillus sp. on the water quality and thermal stress response of Penaeus monodon postlarvae during culture are also currently being investigated. The efficacy of commercial probiotics (PRO W, PRO 2) and disinfectant (PUR) to control acute hepatopancreatic necrosis disease (AHPND) and luminescent vibriosis in P. vannamei culture is likewise being investigated. Activity 5: Rationalize the need and application of diagnostics that will ensure biosecurity within culture systems The sanitary qualities of two major oyster production areas in Capiz Province are investigated for fecal coliform count, Escherichia coli count, Vibrio parahaemolyticus count, and presence of V. cholerae and Salmonella, in the rearing water and oysters meat, respectively. Oysters are filter feeders and can concentrate bacteria from surrounding seawater in their digestive system. E. coli is normally found in the feces of humans and warm-blooded mammals, hence, the ability of E. coli to survive in the water of oyster production areas serves as indicator of fecal contamination. The presence of heavy metals in the oyster meat is also monitored. Relaying stations are also monitored for their suitability, in terms of fecal coliform count, to provide for the need to relay or depurate oysters. Activity 6: Rationalize the need and application of diagnostics that will ensure biosecurity within culture systems PROGRESS/ACHIEVEMENTS OF ACTIVITIES IN THE YEAR 2017 FIND EFFECTIVE ALTERNATIVE PROTEIN SOURCES TO FISH MEAL AND FISH OIL IN DIETARY FORMULATIONS For tilapia larvae, grouper fingerlings and abalone, feeding experiments are ongoing including the study on amino acids required by sea bass growth. Confirmatory runs were conducted this year to verify results obtained in earlier runs. Currently, the amount of crude fat in the mass-produced thraustochytrid was still low ( %), hence, isolates were prepared in petri dishes with the aim to increase crude fat content of the algae. Results showed that crude fat in the isolates was high at a level of 20%. This information is important as this could be a good alternative to marine lipids in formulated diets for aquaculture species. PROMOTE PRACTICES AND STRATEGIES IN NUTRITION TO IMPROVE PRODUCTION Postlarvae of P. indicus were successfully produced in the hatchery and stocked for grow-out culture. Better performance was noted in shrimp fed commercial diet low in crude protein content (40%) which will be verified in another run. Male with sperm and mated female were noticeable during harvest and These studies will have confirmatory runs to achieve objectives. Amino acid studies needed longer period to undertake. 3

4 could be sources of breeders. A collaboration was agreed with a farmer to use his pond for the grow-out culture of hatcherybred P. indicus where all inputs are documented to determine profitability of P. indicus semi-intensive pond culture. TESTING THE EFFICACY OF INDIGENOUS PROBIOTICS Ongoing study Effects of Poly-ß-hydroxybutyrate-accumulating Bacillus species on the water quality and thermal stress response of P. monodon postlarvae during culture The protective effects of Bacillus sp. JL47 containing different levels of amorphous Poly- -hydroxybutyrate (PHB) in a model culture system using gnotobiotic Artemia were examined. The Bacillus isolate was grown to accumulate different levels of amorphous PHB (29% and 55% PHB on cell dry weight) and was fed to gnotobiotic Artemia nauplii during a Vibrio campbellii LMG challenge test. The results showed that Artemia nauplii fed the Bacillus sp. JL47 containing 55% PHB attained a significantly higher survival than those Artemia fed the Bacillus sp. JL47 containing 29% PHB. Moreover, a complete protection against pathogenic V. campbellii was observed in Artemia fed the Bacillus sp. JL47 containing 55% PHB since no significant difference was observed between this treatment and the non-challenged control. The data suggest that, the protective effects of Bacillus sp. JL47 is superior when it contains higher amount of amorphous PHB and that the amorphous PHB is suggested to be a main determinant in the protective effect of the Bacillus sp. JL47. In another study, P. monodon PL (1.75 cm ± 0.75 S.D.) were acclimatized for a week and cultured for 30 days in 50 L nursery tanks at 5 shrimps L -1. Shrimps were fed shrimp diet supplemented with PHB-accumulating Bacillus sp. JL47 at 5 g kg -1 feed (0.5%). Shrimps fed diet without Bacillus sp. JL47 supplementation was used as control. At 7,14, 21 and 30 days of culture (DOC), 30 shrimps from each tank were transferred in glass aquaria containing 7 L seawater and subsequently bath challenged with V. parahaemolyticus 1213 strain at a dose of 1 x 10 5 cell ml -1 for 24 h. Shrimps were eventually monitored for 7 days. Results showed that survival in all treatments was very low in shrimps challenged after 7 (0% survival in all treatments), 14 (control: 0% survival; JL47: 0.83% survival) and 30 days (control: 16.7% survival; JL47: 14.8% survival) of feeding (treatment). However, at 21 DOC, challenged shrimps fed with Bacillus sp. JL47 showed higher survival (52.5% survival) compared with the control (16.7% survival). Use of commercial probiotics (PRO W, PRO 2) and disinfectant (PUR) to control acute hepatopancreatic necrosis disease (AHPND) and luminescent vibriosis in P. vannamei Contracted research The practical applications of commercial probiotics (PRO W, PRO 2) and disinfectant (PUR) to control acute hepatopancreatic necrosis disease (AHPND) and luminescent 4

5 vibriosis in P. vannamei in penaeid shrimps were investigated. Ongoing experiments focus on the effect of PRO 2 on the bacterial level/ load and composition in the gut of P. vannamei and rearing water and effect of PRO W on water quality and as well as growth and survival of P. vannamei when added in the rearing water. In addition, the effects of INVE probiotics (PRO W, PRO 2) and disinfectant (PUR) on the survival of P. vannamei against V. parahaemolyticus and V. harveyi challenge are being examined. RATIONALIZE THE NEED AND APPLICATION OF DIAGNOSTICS THAT WILL ENSURE BIOSECURITY WITHIN CULTURE SYSTEMS Establishment of sanitary quality of oysters (Crassostrea iredalei) and their culture environments In an attempt to determine the microbial quality of oysters grown in Capiz province, major oyster production sites located along the coastal villages of Roxas City (Culajao [n=3 sampling stations] & Cagay River [n=5]) and municipalities of Ivisan (Cabugao Bay [n=7]) and Panay (Culajao River [n=5]), Capiz province, Panay, Western Visayas, Philippines, were examined monthly for their microbiological quality, i.e. quantity of Escherichia coli, Vibrio cholerae, V. parahaemolyticus, and Salmonella in oysters meat and intervalvular fluid and fecal coliforms of the rearing water, over a period of 2 years. The monthly coliform count in the water samples collected from all sampling stations were generally high ( 540 MPN/100 ml) regardless of the sampling period (wet or dry season). Similarly, the monthly E. coli count in oysters meat and intervalvular fluid were typically high (330~24,000 MPN/100 g) particularly during the warm dry months of the year, i.e. April to June. V. cholerae was not detected in any of the oyster samples examined while V. parahaemolyticus count was within acceptable range. Salmonella was erratically detected in oysters collected from all sampling stations examined. Relaying oysters in an approved area in Cabugao Bay was likewise attempted. As a result, E. coli count in contaminated oysters significantly dropped from 24,000 MPN/ 100g to 20 MPN/ 100g after 2 weeks of relaying, suggesting the practicality of this technique in rendering raw oysters safe for human consumption. Taken together, current data indicate the urgent need to improve the quality of raw oysters cultured in these sites through the adoption of environment friendly culture methods such as raft or long line together with the establishment of a National Shellfish Sanitation Program whose primary task shall include continual monitoring of the microbiological quality of oysters and their culture environments DOST- PCAARRD GIA funded study. 100% completed; terminated September

6 PREVENTION AND MITIGATION OF DISEASES IN DOST- PCAARRD CULTURED MUDCRAB GIA funded study Because vibriosis and white spot syndrome virus (WSSV) persistently cause mortality in mud crab, i.e. vibriosis in the hatchery phase and WSSV in the grow-out phase, indicators responsible for disease occurrence or outbreak in cultured shrimps are currently being investigated. Shrimp mortality due to WSSV infection could be due to the viral load and environmental conditions such as low water temperature. Also, WSSV might be present in the pond soil and water, and may serve as vehicle for infection. Thus, to address these concerns, the threshold levels for WSSV in the water, soil, and system of mud crab that may result in infection and mortality or outbreak are currently being examined in vitro and in vivo. PROPOSED FUTURE ACTIVITIES FOR THE YEAR 2018 Planning of the Project Activities Confirmatory runs of feeding experiments Procurement of commercial feed for P. indicus in ponds and monitoring of mortality of the wild breeders in the hatchery during production. Study on replacers for soybean meal in formulation for high 2018 value species Study on methods to prevention or mitigate the effect of Ongoing (Year 2) diseases in mud crab culture Effects of Poly-ß-hydroxybutyrate-accumulating Bacillus species on the water quality and thermal stress response of P. monodon postlarvae during culture 2018 SEAFDEC/AQDfunded study Expected Outcomes/Outputs Nutrition and Feed Development Proposed confirmatory runs of studies conducted Use of the algae, thraustochytrid, as a protein source for the abalone diet pursued Replacement studies for soybean meal using different sources be proposed/conducted in formulations for high value species Prevention and mitigation of diseases in mud crab culture Viral load (WSSV) in water/soil/mudcrab that would result in infection/mortality quantified using qpcr; Environmental parameters that would affect infection/mortality identified Epidemiological data generated Effects of Poly-ß-hydroxybutyrate-accumulating Bacillus species on the water quality and thermal stress response of P. monodon postlarvae during culture 6

7 Bioremediation activity of PHB-accumulating Bacillus on the water quality of P. monodon postlarvae (PL) culture specifically the removal of ammonia, nitrite and nitrate determined Effects of PHB-accumulating Bacillus spp. On the growth, survival, and m RNA expression of hs70 and propo in P. monodon PL exposed to high water temperature (35 C) elucidated Effects of PHB-accumulating Bacillus spp. on the survival of P. monodon PL exposed to high water temperature (35 C) and subsequently challenged with VPAHPND strain examined 7