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Tài liệu Probiotics and their use in

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PROBIOTICS AND THEIR USE IN AQUACULTURE April 2006 10th Aquaculture Insurance and Risk Management Conference Presented by: William P. Long Chief Executive Officer Epicore BioNetworks Inc. BASIC AQUACULTURE MARKET NEEDS  To survive and make money  To overcome problems of:  Pond crashes  Farm abandonment  Low survival  Poor quality animals  Low weights  Poor feed conversion ratio (FCR) It’s not a hobby; it’s a business! MURPHY’S LAW  Whatever can go wrong, will go wrong!  Mismanagement  Weak PL, bad feed, inadequate oxygen, poor harvest procedures  Natural events  Weather, predators    Disease Theft Crop market prices THE SCIENCE OF SURVIVAL Through microbiological science aquaculturists can fight Murphy's Law Probiotics are a natural, environmentally friendly application of microbiology TRADITIONAL DISEASE CONTROL UNDER FIRE  Many older antibiotics proven unsafe so are banned from all uses  Shrimp with antibiotic residues cannot be sold in many major markets  State of art antibiotics should be reserved for humans ROLE OF ENVIRONMENTAL MICROBIOLOGY IN AQUACULTURE  Pollution control  Bioremediation of wastes  Cleaner water & pond bottoms  Disease resistance imparted by creating a lower stress growing environment  Probiotic action  Directly protects animals from disease  Pathogenic Vibrio parahemolyticus, Vibrio harveyi bacteria, Aeromonas  Indirectly protects from some viral diseases POLLUTION CONTROL  Waste is major problem in aquaculture pond and hatchery waters  Affects animal health and vigor  Lowers harvest yield value  Forces frequent water exchange    A biosecurity risk Bacteria are nature’s chosen waste degraders End result of microbial action is biomass - a soil amendment Harnessing the power of nature’s microbial workforce BIOREMEDIATION MODE OF ACTION   Aquaculture wastes are organic in nature Microorganisms “eat” organic wastes  Bacteria + N + C + P + O2 = More Bacteria + H2O + CO2  Microorganisms digest pollutants  Ammonia: very toxic to crustaceans and fish  Nitrite: very toxic to crustaceans and fish  And is food for disease causing Vibrio  Nitrate: too much causes algae crashes  Pond bottom waste: release nutrients in older ponds to promote natural algae bloom without added fertilizer WHAT IS A PROBIOTIC A live microbial supplement that benefits the host animal – From the Greek “probios”:  Pro = “for”  Opposite Bios = “life” of antibiotic – A microbial killer or suppressant PROBIOTIC MODES OF ACTION  Competitive exclusion    Out-competes pathogenic bacteria for nutrients Displaces pathogens from gut wall sites Produces acids in gut to inhibit pathogenic bacteria  Bacteriocin (antimicrobial) excretion  Repels or kills pathogenic bacteria  Stimulates immune response  Aids digestion   Produces enzymes to help digest & absorb feed Reduces toxic amines PROBIOTIC BENEFITS vs. ANTIBIOTICS         Probiotic use eliminates need for antibiotics Probiotics create no illegal residue Bacteria cannot develop resistance to probiotics but can to antibiotics Antibiotics lead to slow growth rate of larvae Probiotics boost immune system of shrimp Probiotics also digest pollutants Probiotics promote high survival so are costefficient to use Cheaper to use probiotics than antibiotics PROBIOTICS AND VIRUSES  Anecdotal evidence that probiotics mitigate pathogenicity of WSSV virus – Pond in Vietnam saved by double does of probiotic after WSSV outbreak – Pond in Mexico with same experience after PCR testing and mortality confirmed WSSV presence Some researchers believe probiotics stimulate shrimp immune response  Some researchers believe that probiotics mitigate WSSV by controlling secondary pathogens  PROBIOTIC COMPOSITION Single strain of live microorganism    Usually bacterial or yeast e.g. Lactobacillus acidophilus, Saccharomyces cerevisae, Vibrio alginolyticus  Lactic bacteria typical of human probiotics Microbial ecosystems     Mixtures of specially selected, live but dormant microorganisms Synergistic mixtures High strength for economy of use Usually are dry powders   Excellent shelf life if kept dry WHY MICROBIAL ECOSYSTEMS?  Teams work better than individuals – Ecosystems work better than single strains  What makes a good ecosystem? – Enough “players” on the “team”  High cell count (cfu = colony forming units) – Enough of the right types of “players”   More than one type (i.e. strain) Too many strains is bad (poor QC, low individual count) – High quality “players” of each type   Best strain for each intended purpose (e.g. enzyme production or specific waste digestion) Safe microorganisms TYPICAL AQUACULTURE PROBIOTIC  Selected live microorganisms like:  Bacillus spp., Lactobacillus spp., Yeast  Soil-based, non-toxic, not genetically modified  Not close relative of pathogens  Minimum strength = 2E+09 CFU/gm      i.e. 2,000,000,000 colony forming units per gram Fortified with a broad spectrum of free enzymes to start waste digestion Contains proprietary growth stimulants Free of pathogens and toxins Biodegradable carrier TYPICAL PROBIOTIC PRODUCT PROBIOTIC SUCCESS FACTORS  Existence of water quality or disease problem  Use proper dosage & treatment frequency  Follow literature or ask local distributor  Time to work  Bacteria, unlike chemicals, take time to work  For curative application allow 24-48 hours  Organic matter present  Add biological growth media to new or lined ponds  Proprietary media or home-made (e.g. sucrose-based)  Salinity  Good probiotics are tolerant but best in salinity <40 ppt  Pond pH – tolerant but best at 6-10  Temperature: Slower at low temperatures AMMONIA DIGESTION Ammonia (TAN) Concentration Over Time at Various Dose Rates of EPICIN EPICIN (mg/l) 4.0 0 error bars represent +/- sd TAN (mg/l) 3.0 10 2.0 50 1.0 0.0 0 1 2 3 4 5 Time (Days) • Probiotics take time to work • Ammonia digestion is dose sensitive SALINITY TOLERANCE 4 TAN (ppm) 3.5 3 2.5 48 37 24 12 0 2 1.5 1 0.5 0 0 1 2 Time (days) 3 ORGANIC CARBON IMPORTANCE 4 TAN (mg/l) 3.5 3 2.5 2 1.5 1 0.5 0 0 22 43 64 86 Total Organic Carbon (mg/l) Works best with organic carbon present
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