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Ridley Aqua-Feed. Asian Shrimp C ulture Update Matthew Briggs Vannamei 101 Co. Ltd. Sponsored by RIDLEY AQUA FEED. Contents. Ridley Aqua-Feed, Narangba. Major Asian Shrimp Producing C ountry Updates Current World Production Statistics New Disease Issues and Management methods
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Ridley Aqua-Feed Asian Shrimp Culture Update Matthew Briggs Vannamei 101 Co. Ltd. Sponsored by RIDLEY AQUA FEED
Contents Ridley Aqua-Feed, Narangba • Major Asian Shrimp Producing Country Updates • Current World Production Statistics • New Disease Issues and Management methods • EMS/AHPNS • IMNV • White Faeces Disease
Ridley Aqua-Feed, Narangba Current Status of Major Asian Shrimp Producing Countries
China Overview Ridley Aqua-Feed, Narangba • 50:50 marine and F/W vannamei culture. Huge, high value and rapidly-expanding local live/fresh market – now importing from other countries as can’t satisfy domestic demands – now net importer and likely to increase • But, since 2009 massive losses due to a mixture AHPNS and other diseases (WSSV, TSV etc.) causing repeated early mortality throughout China • 2010 and 2011 first crop lost 80-90% in most areas, then recovered in second crop, but then 2012 – so far first 2 crops lost at 30-90% depending on region • Production losses estimated at 487,000 mt worth $2.1 billion between 2010-2012 (past 3 years) • Many hatcheries still dumping PLs as many farmers frightened to stock ponds as can’t stand more losses
Thailand Overview Ridley Aqua-Feed, Narangba • Until this year good success due to wholesale (99%) adoption of vannamei, high technology, CP success and value added processing, with Thailand by far largest exporter of shrimp in world • But from Sept. 2011 EMS/AHPNS hit central/east Thailand. • Early 2012 Thai production good, but now EMS causing big and increasing problems • Also, conflicts between farmers and processors, together with low demand from EU, Japan and USA meant prices declined 25% from February 2012 until now • Plus still have problems with WSSV in cold weather and white faecesdisease, slow growth, plus some losses due to flooding • Production estimate from Thailand this year revised down from 650,000-480,000 mt - Production loss 123,000 mt worth $433 million between 2011-2012 (2 years) • Some SPF monodon production (CP and Moana) ongoing and good results, but small scale due to lack of supply
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Vietnam Overview Ridley Aqua-Feed, Narangba • Helped by extensive Government support, huge culture areas, and introduction of vannamei, but lately being hit with increasing disease, antibiotic residue, environmental degradation and salinationproblems • 2010-11-12: EMS problems getting worse with huge losses, especially with monodon in huge Mekong Delta region, up to 100,000 ha in 2011 and could be worse this year • Production loss 133,000 mt worth $531 million between 2010-2012 (last 3 years) • Continuing problems with WSSV and antibiotic residues • Processing plants largely empty due to lack of product and high demand from China (taking shrimp from Vietnam) – have been importing >400 mt shrimp/d from Thailand
Indonesian Overview Ridley Aqua-Feed, Narangba • Mostly (>85%) vannamei intensive culture, plus large production from ext/traditional monodon and vannamei ponds • Farmers now using new biosecurity and management to accommodate IMNV and getting better results, but mostly with lower density, bioflocsand polyculture with tilapia, but are some super-intensive farms (up to 55 t/ha in partial harvest biofloc farms) • Production picking up last 2 years in absence of EMS and lack of supply from other countries driving up price • CP recovering to >50% of previous production before IMNV, but had to abandon AWS (Ex-Dipasena) • Also using closed systems and partial harvesting • Return to monodon or stylirostristried, but not successful due to WSSV outbreaks
CPP, Indonesia Ridley Aqua-Feed, Narangba
Indian Overview Ridley Aqua-Feed, Narangba • Past few years India stagnated due to exclusive monodonuse and disease problems with WSSV and LSS • But now low density vannameiculture expanded rapidly 2010-2012 producing a lot of big sized shrimp (up to 40g) • Shrimp grow fast & big in high temperatures, even in freshwater polyculture with few disease issues • Vannamei now 56% of total production (100,000 mt of 180,000mt production in 2011) • But government regulations and interference limiting expansion • And still lack of processing capacity coupled with low demand from abroad leading to severe price reductions so far this year (just picking up again now due to lack of supply from other main Asian producers)
Ridley Aqua-Feed, Narangba Philippines, Bangladesh and Malaysia • Philippines: • Stagnant with reliance on monodon, now vannameipicking up with good fresh market, but production still limited and lack of processing for exports • Now 70% vannamei, 28,000 mt out of 40,000 mt • Bangladesh: • Stagnant due to low technology, disease problems, lack of disease checking or SOPs, persistence with diseased wildmonodonand antibiotic residues leading to difficulties with marketing • Now seriously talking about importing vannameidue to continuing problems withmonodonculture and exports • Malaysia: • Began suffering from EMS last year and back worse this year and spread to E. Malaysia also – vannamei farming lost 57% from 70,000-30,000 mt over past 2 years, prompting some return to monodonfarming, particularly with domesticated SPF stocks which are giving better results and farms turning to biofloc system which are also often unaffected by EMS • Malaysian plants also empty and importing cheap shrimp from Thailand
Ridley Aqua-Feed, Narangba World Shrimp Production Statistics
World production of cultured marine shrimp 1991-2013 Current disease and economic problems Intro. Vannamei to Asia Rapid growth in Asia Stagnation with WSSV, YHV in Asian monodon Estimated Sources: FAO (2011) for 1991-2009; GOAL (2011) for 2010-2013.
Asian Shrimp Production Ridley Aqua-Feed, Narangba
Latin American Shrimp Production Ridley Aqua-Feed, Narangba
Ridley Aqua-Feed, Narangba New Disease Issues
Ridley Aqua-Feed, Narangba Early Mortality Syndrome (EMS) In some cases Acute HepatoPancreatic Necrosis Syndrome (AHPNS)
EMS/AHPNS • First noticed in in intensivevannameiponds in S. China in 2009 (ignored) and then in March 2010 in monodonponds in S. Vietnam and mid 2010 in West Malaysia (Pahang and Johor States) • Came back stronger in March 2011 in 100,000 ha in Mekong delta and Central Vietnam, plus S. China and most of W. Malaysia much worse & again in early 2012 • Now, September 2011 spread to Chantaburi/Rayong/ Chachoengsao in Thailand (becoming more serious) and in April 2012 Sabah and Sarawak in E. Malaysia • Total losses between 2010-2012 (last 3 years) about $3.3 billion or 800,000 mt of shrimp – mostly due to EMS (AHPNS and others) • Unsure if same problem or not, but histo-pathological symptoms characteristic of AHPNS can be seen, although some cases of EMS are caused by other problems and not all by new AHPNS syndrome !
AHPNS Definition • Dr. Donald Lightner says possible idiopathic condition with a clear case definition: • Stage 1: Acute progressive degeneration from proximal to distal end of the tubules of the HP. Medial to distal destruction of B, R & F cells, Decreased cytokine function, No cellular differentiation, and Lack of mitotic spindles in E-cells, Prominent karyomegaly and sloughing of tubular epithelial E-cells in HP • Stage 2: Intertubularaggregation of haemocytes • Stage 3: 2o bacterial invasion leading to multiple Vibrio Spp. (& other) infections especially in the HP • Also, Flegal recently found abnormal blebbing of the HP tubule margins in the absence of bacteria (happens with toxins or cell apoptosis) • These histological signs must be present in AHPNS
EMS Causes ? • Still unresolved, but many theories: • Initially thought to be caused by toxic agent – perhaps from algae or pesticide residues, with secondary bacterial infections • Tested and not: viral, feed toxin, microsporidian, intracellular bacteria, pesticide toxicity etc… • Now suggestions of new bacterial pathogens perhaps resulting from use of bad probiotics (i.e. Psuedomonasand Photobacterium spp.) in hatcheries (AHPNS symptoms now confirmed from some hatcheries and evidence of hatchery origin for poor performing ponds), but others also questioning if could be algal derived toxin (some positive results)
Management Techniques • Real causes of disease are still unknown and many farmers maintain should be called BMS - (Bad Management Syndrome) • However, due to severity, sudden onset and rapid spread of syndrome it seems likely that there is a pathological or toxic agent responsible • Although both monodon and vannamei are affected, initial results show wild monodon worse affected, whilst domesticated SPF monodon are more resistant • Meantime, until definitive causes are established only good management practices and avoidance of known risk factors can be used
Management Techniques • Good preparation of the pond environment : Remove sludge &/or completely dry the pond bottom to control organic nutrient loading • Thoroughly disinfect (of virus and bacteria) water in RV and ponds prior to stocking • Employ biofloc management technology or control algal blooms to limit b/g or d/f blooms • Low salinity culture (with mineral balancing) • Stock only healthy post larvae (preferably > PL10) from reliable hatcheries (check condition of the HP). Ensure use of only approved probiotics • Stock based on pond carrying capacity (max forvannamei13-15 mt/ha and monodon 6-8 mt/ha) • When CC reached (and feeding/growth slows and/or DO falls) conduct partial or full harvests
Management Techniques • Control feeding to about 12 kg per 100,000 pcs/day of shrimp at 30 d with average body weight at 2.0-2.5 g. The accumulated feed at 30 d should not be <250 kg. Reduce feeding when water temperatures <26 °C. Maximum daily feed increment should only be 500g/100,000 shrimp. Add immune stimulants to diets to improve resistance • Maintain DO >3-4.0 ppm near the edge of sludge. Provide 1 HP/400 kg of biomass. When adequate oxygen is provided, problems with toxic hydrogen sulphide, ammonia and nitrite can be avoided • Try to avoid stocking in cold weather or during periods of fluctuating environmental parameters (temperature/ salinity) • Use of domesticated, selected monodonstocks where available
Use of Immunostimulants to Control EMS ? • Some work done by GS Biotech this year in East Malaysia with their general immunostimulant product Beta defence feeding at 3% vol/wt in diet from day 1 throughout 78 day cycle with vannamei • Product contains LPS, Beta-Glucans, Amino Acids and Nucleotides developed using a special fermentation technique • Previously found effective at preventing WSSV in monodon farming in Malaysia and the Philippines • Results against EMS: • Stocked 40-50 PL/m2 – 6 treated ponds got average 80-90% SR at FCR 1.34 and 16 g at 6.1 mt/ha after 78 days, whilst 6 control ponds were all harvested by 50 days when they were at just 11 g with <50% SR
New Emergency Consultation • On 9-10 August 2012 DAFF Australia /NACA, Thailand are organizing an emergency Asia Pacific Regional Consultation on EMS/AHPNS in Bangkok, Thailand • Many world experts and over 70 regional representatives will be present to discuss latest information and findings and look for a way forward to combat this threat
Ridley Aqua-Feed, Narangba Infectious Myonecrosis Virus (IMNV)
Brazil IMNV Indonesia
Ridley Aqua-Feed, Narangba IMNV Characteristics • IMNV originated in Brazil in 2002 and spread to Indonesia in 2006 with import of live infected vannameibroodstock to a hatchery • Since then spread throughout Indonesia and caused $1-2 bn in direct production losses to date but problems easing lately • Causes coagulative muscle necrosis and death from 6g onwards at 30-50% mortality rate – requiring early harvesting and loss • Spread mostly through movement of infected PLs, but has many crustacean and other hosts and lives >2 mo. as free virus in water • Main problem is with vannamei(monodonlargely unaffected)
Spread of IMNV around Asia ? Ridley Aqua-Feed, Narangba • Many persistent rumours from all over Asia (Phils, China, Vietnam)– but continual analysis by Flegals group in Bangkok never confirmed positives from any Asian country except Indonesia (2006-2012) • Many people see white muscle and think IMNV Many cases are not IMNV, but muscle cramp syndrome, MrNV, microsporidians& bacterial infections in HP but no Ricketssias or other viruses • Positive results from other countries by PCR analysis probably false positives with non-specific IQ2000 kit • Still presents huge risk for vannameiindustries throughout Asia – leading to banning of imports of Indonesian shrimp by other Asian countries
Management Strategies for IMNV Ridley Aqua-Feed, Narangba • Reducing stocking densities – down to 70-80 PL/m2 as shrimp do not normally suffer before 60 days and densities lower than 70 are less affected • Increased biosecurity in all areas • Using batch all in : all out stocking practices for farms • Disinfect all new water with crustacide inside lined reservoirs covering 20-30 % of pond area • Bird nets to prevent dropped shrimp • Enter pond and siphon out sediments (up to daily) • Replace vannamei with monodon or stylirostris ? • Using closed biofloc systems in E. Java – better results • Polyculture with Tilapia/milkfish (up to 0.5 fish/m2) – giving good results
Ridley Aqua-Feed, Narangba White Faeces Disease (WFD)
WFDSymptoms • This is relatively new problem now forvannameiin Thailand (Jan 2010 - ongoing) and increasingly in other countries around Asia (China, Vietnam, Malaysia, Indonesia etc.) • Signs: Start 20-50d, but severe after 50-90 days • White faeces around pond banks and in netted shrimp (yellowish mid-hindgut) • Severe reduction in feed intake leading to empty guts and shrunken white HP, soft and thin shell • Notice weak, emaciated shrimp in feed net, dribbling mortality and at harvest overall 30-40% decrease in production
WFD Possible Causes • Thought due to a combination of bacterial (Vibrios and others), gregarines, algal toxins and poor quality feed, but Latest research indicated presence of a new Enterocytozoon sp. microsporidianparasite in many cases • Can weaken shrimp, retard growth and cause stress • Detectable by in-situ hybridization technique and new PCR developed by Flegal • Presence in intestinal epithelial cells and throughout HP • Highly infectious and spores can be transmitted through intermediate hosts and even directly shrimp-shrimp
In situ Hybridization for Microsporidian Difficult to see by histopathology, but easy with IS-H
Extenuating Circumstances • Overfeeding: high water temperatures lead to increased appetite (25%), then overfeeding and reduced water quality – esp. low DO • Poor pond bottom conditions and anaerobic soil leads to 2o bacterial infection and stress with Vibrio entering shrimp though damaged midgut • Possibly associated with sudden high temperatures and salinities during hot, dry season, especially at higher densities (>40/m2) • Brood/PL can be infected (esp. if fed with infected fresh feed)
Possible Treatments For bacteria: • Probiotics (5-10g/kg for 20 days), sometimes mixed with Azomite (5g/kg food) • Organic acids at 2-10g/kg • Pineapple syrup at 10ml/kg feed • “Bokashi” (betel leaf and EM) in Vietnam • Treat inlet water to kill bacteria and hosts with chlorine, BKC or Potassium permangante Feed supplements: • Ginger, garlic, tamarind, probiotics, Bokashi, organic acids, mannan oligosaccharides, immunostimulants, enzymes, Vitamin C, spirulina, carotenoids etc…
Possible Treatments For Gregarines/microsporidians • Garlic paste/ powder (10g/kg 3-5 */d for 2-3 d) • Antihelminths/Antibiotics for 10-14 consecutive days: albendazol or sodium monensin(Elancoban) 3-6 g/kg of feed For B/G algae (often microcystis): • 200 kg/ha gypsum or 1ppm BKC • Fertilize for high N:P ratio (15-30:1) with sodium nitrate (100-180kg/ha), silicate and azomite, and can use phoslok to tie up P • Disinfect ponds between cycles !
Management Strategies • Reduce stocking density (max 80-90 PL/m2) • Ensure Broodstock & PLs used are SPF, clean and no white faeces/spots/gregarines & good HP • Biosecurity & disinfectionfor all personnel and equipment – prepare pond bottom ! • Maintain pond bottom through proper prep., removal of disease vectors & dead shrimp and conduct weekly chaining & daily release of sediments via central drain Maintain bloom through controlled fertilization • Kill intermediate hosts of gregarines and micro-sporidians (snails, mosquito larvae, polychaete worms, fish, crabs, birds etc.)
Management Strategies • Proper water circulation and aeration (1 HP/400 kg biomass to maintain DO>4) to maintain environmental conditions – if conditions improve – shrimp can recover and behave normally thereafter • Use Best feed possible with highly digestible ingredients and check consumption regularly • Do not overfeed at start – as for management of EMS • Stop feeding for 5 days at first sign to reduce OM accumulation then use treated feed • Use Autofeedersto prevent waste food accumulation • If all else fails - harvest early (at least partial harvest if carrying capacity reached at 1.3-1.5 kg/m2) if shrimp reached marketable size already
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