| Probiotics improve function in farmed shrimp production, regulation of waterquality, improve the immune system and other aspects of shrimp has been universallyrecognized. Biological floc in recent years been recognized worldwide ecologicalfarming model, the farming methods can not only effectively reduce the breeding ofharmful inorganic nitrogen in water purifying water, but also that farmed shrimpprovide nutrients, improve immunity and nonspecific resistance. The experiment wasisolated from shrimp culture ponds identified and obtained by screening bacterialstrain with efficient denitrification capacity, and add it to the culture water by addingcarbon adjustment C/N to form a biological floc.1The research ofa strain of heterotrophic nitrification denitrification bacteriascreening and its characteristicsA strains with capable of nitrification and denitrification was isolated byenrichment culture and separation purification from bio-floc of shrimp culture ponds.By morphology,16S rRNA sequencing and analysis of the strain Bacillus megateriumsimilarity of99%. This strain was named as Bacillus subtilis201205311-D-3. By thestrain at different temperatures, pH and salinity of the strain derived growth optimumgrowth temperature is30℃, optimum growth salinity of25, the optimum pH was8.0.By the strain grown in different media and nitrogen removal efficiency of variousinorganic nitrogen found in most of the strain by ammonia as the sole nitrogen sourcethe best growth medium. Respectively with ammonia, nitrite and nitrate as the solenitrogen source medium for various inorganic nitrogen removal efficiency was (91.33±0.41)%,(87.53±0.68)%,(79.79±0.34)%. Three nitrogen exist in the medium, thefirst use of the strain of ammonia. The experimental results show that the strain201205311-D-3highly efficient nitrification and denitrification capacity, suitable foruse in shrimp farming and water environments. 2、Impact of two strains of a single strain of L. vannamei of seedling survival andanti-WSSVThe Bacillus megaterium201205311-D-3and beautiful Halomonas201107270102add water aquaculture water so that the concentration of bacteria was1×106cfu/mL, two kinds of bacteria in the feed ration parcels vannamei seedlings. Inthese two ways of feeding20days after treatment, the statistical survival rate ofseedlings, and be fed poison attack diseased WSSV infection,14days after seedlingmortality statistics. The experimental results showed that: the two treatments shrimpseedling survival rate were higher, adding a beautiful group of Halomonas201107270102shrimp shrimp seedlings highest survival rate (74.17±1.18)%. Shrimpseedlings for each treatment group were anti-WSSV effect, adding tremendousBacillus201205311-D-3group relative protection against WSSV highest rate of56.67%, significantly higher than the other groups and the control group (P <0.05).Add Bacillus megaterium and beautiful Halomonas and wrapped into two kinds ofbacteria can significantly improve feed fed shrimp seedling resistance to WSSVinfection.3、Two strains of micro-organisms in a specific function vannamei farming inbiological flocFor the role of vannamei farming in biological floc study of two bacteria,Bacillus subtilis and the great beauty as well as two Halomonas bacteria added to theamount of mixing vannamei farming water, and add the brown sugar as organiccarbon, biological floc culture, and changing the water normal farming and farming asnormal without changing the water control treatment. The results showed that theaddition of carbon and the amount of bacteria in the biological floc generationbio-floc breeding group was significantly higher (P <0.05), which added to the mixedstrains better. Adding organic carbon and bio-floc bacteria breeding group to reduceammonia and nitrite nitrogen content aquaculture water, improve the survival rate ofL. vannamei and promote the growth of shrimp. |
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