Research On The Effect Of The Aquiculture Water Environment And The Growth Of Carps By Two Strains Of Probiotics

With the rapid development of the aquaculture production in China, someproblems also appeared. First of all, the-derived sewage of the industry andagriculture discharged into the culture ponds. On the other hand, the breeding densityis too large caused much excreta and residual feed deposited in the culture ponds.Using traditional methods such as mechanical water changes and dosing chemicalreagents to deal with the problems of water pollution, rapid onset, but the economiccost is too high and prone to secondary pollution.In this thesis, Q and G strains preliminary identification tests include: Gramstain test,Capsular stain test, Spore stain test, Flagella stain test, Indole test, Methylred test, VP test,H2S test,H2O2test, Liquefaction of gelatin test,Oxidation of ethanoltest, Oxidation of Acetic acid test,Litmus milk test etc. The results showed that Qbacteria belonging to the Bacillus Shide, is Bacillus subtilis. G bacteria belonging tothe Brevibacillus Shide, is Brevibacillus brevis. The Ministry of Agriculture hasapproved Bacillus subtilis put as a feed additive in aquaculture production,but a littleresearch on Brevibacillus brevis. The best dosage of Bacillus and Brevibacillus shouldstudy more.To investigate the effect on the growth and the aquiculture water quality of carpsby two bacterias. Carps which in20L water were exposed to different doses ofBacillus subtilis and Brevibacillus brevis0.1%,0.3%,0.5%respectively for60days,and the control group was done at the same time. Continuous measurements of thephysical and chemical indicators of water every3days are include: Chemical oxygendemand (COD), Ammonia nitrogen, Dissolved oxygen (DO), pH, Transparency(SD).Measured phytoplankton biomass in every10days and observed water color.After breeding60days, test the activities of digestive enzymes of carps. full-grownrate was be tested every10days. The following conclusions:(1) Bacillus subtilis and Brevibacillus brevis can effectively reduce the CODand Ammonia nitrogen concentration in water,.To maintain the dissolved oxygen inthe6.8to7.1mg/L, the pH of the water in the range of7.1to7.3, to maintaintransparency about22cm. (2) The amount of phytoplankton in the Bacillus subtilis group andBrevibacillus brevis group compared to the control group improved by33.6%and48.7%.Water color remained brown and yellow-green.(3) After60days, the control group full-grown rate increased by14.25%.Bacillus subtilis and Brevibacillus brevis groups’ full-grown rate increased by27.20%and22.30%.(4) The results showed that Bacillus subtilis could promote the digestiveenzymes activity in the intestinal of carps(p<0.01). In the0.5%group, the proteaseactivity in the intestinal was promoted obviously by97.17%; In the0.3%group, theamylase activity in the intestinal was promoted obviously by60.31%,little effect onthe activities of digestive enzymes in the hepatopancreas. Brevibacillus brevis couldpromote the amylase activity of carps(p<0.05). In the0.5%group, the amylaseactivity in the intestinal was promoted obviously by61.70%; the amylase activity inthe hepatopancreas was promoted obviously by38.79%, little effect on the activitiesof protease of carps.(5) The optimal dosage of Bacillus subtilis is0.3%.The optimal dosage ofBrevibacillus brevis is0.5%.