Screening And Identification Of Deodorant Strains From Swine Manure And Preliminary Application Of Compound Bacteria Agents

Although with the rapid development of our country's livestock and poultry,the large amount of excrement and sewage discharged from livestock and poultry farms has a serious impact on the environment.Among them,the odor gases?NH₃ and H₂S?produced by livestock and poultry excrement can not only pollute the air,but also endanger the health of humans and livestock and affect the performance of livestock and poultry production performance.Therefore,it has become very important and urgent to control the odor gas pollution of livestock and poultry manure.The treatments of odor gases in livestock and poultry manure includes physical,chemical and microbiological methods.However,physical and chemical methods for deodorization are expensive,high technical requirements,and lead to secondary pollution easier.And microbiological methods for deodorization are less cost,simpler operation,and effective.Microbiological methods for deodorization has become the main way of deodorization in livestock and poultry excrement.In this study,used a dilution coating method to isolates strains from composting manure and activated sludge in order to develop compound strains that can effectively inhibit the volatilization of odor gases from swine fecal.Next,11 strains that could degrade NH₃ and H₂S were screened by NH₃ selective medium and H₂S selective medium,named as N1?N5?M1?M4?MA1?MA3?MA4?MA5?G1 and G4.According to morphology and molecular biology methods,identification of 11 isolated active strains for species identification.The identification result is as follows:N1 is Bacillus subtilis,N5 and G4 are Bacillus licheniformis,M1 is rhamnose lactic acid bacteria,M4 strain and MA3 strain is Bacillus amyloliquefaciens,MA1 is identified as Rhizopus oryzae,M2 is Acinetobacter calcareous,MA4 is A Bacillus vegetative Bacillus,MA5 is Bacillus cereus,G1 is Pichia kudriazzi.According to reports,MA5 and M2 strains are conditional pathogens,Exclude them for safety reason.In order to study the removal of NH₃ and H₂S in swine manure from each isolate,7isolates of N1,N5,M1,MA1,MA3,MA4 and G1 were respectively injected into fresh swine manure,at the same time set up untreated fresh swine manure as control.After 10days at 30°C,determination of cumulative release of NH₃ and H₂S from swine manure using boric acid absorption Kjeldahl method and zinc amine complex absorption colorimetry,and calculate the removal rate of NH₃ and H₂S for each strain.The results showed that compared with untreated swine manure,MA3 had the highest removal rate of NH₃ in swine manure from 7 single strains,which could reach 85.88%.G1 had the highest removal rate of H₂S in swine manure,up to 87.43%.It shows that MA3 has the best removal effect of NH₃ in swine manure,and G1 has the best removal effect of H₂S in swine manure.Then,we put five strains of N1,N5,MA1,MA3,and G1 into the feces water,and untreated manure water was set up for the purpose of study the effect of each isolate on the state of manure.After 10 days at 30°C,the results showed that the water samples treated by the 5 strains were more clear than the blank control group.Among them,the transparency of water samples treated by MA3 is the highest and the difference is significant.It shows that the five isolates can increase the transparency of the feces water,of which MA3 has the most obvious effect.According to the combination of N1,N5,MA1,MA3 and G1 strains on the rate of NH₃ and H₂S removal from swine manure,we prepared seven compound preparations named A,B,C,D,E,F and G respectively.Group A includes MA3,G1,N1,N5,and MA1isolates strains,Group B includes MA3,G1,N1,and N5 isolates strains,Group C includes MA3,G1,N1,and MA1 isolates strains,and Group D includes MA3,G1,N5,and MA1isolated strains,E group includes MA3,G1 and N1 isolates strains,F group includes MA3,G1 and N5 isolates strains,and G group includes MA3,G1 and MA1 isolates strains.In order to study the effect of each compound preparation on the removal of NH₃ and H₂S in swine manure,the above-mentioned 7 groups of compound inoculum and commercial compound microbial preparations were respectively put into fresh swine manure,and an untreated fresh swine manure was set up simultaneously.After treatment for10 days at 30°C,the Kjeldahl adsorption method and the zinc amine complex absorption colorimetric method were used to detect the cumulative release of NH₃ and H₂S in the swine manure,and calculate the removal rate of NH₃ and H₂S for each compound preparation.The results showed that compared with the untreated fresh swine manure,among the 7 groups of compound inoculums,the removal efficiency of NH₃ and H₂S in the swine manure from the group C compound preparations was the highest,reaching 88.75%and 90.50%,respectively.The removal rates of NH₃ and H₂S by commercial composite microbial preparations were 85.20%and 74.54%,respectively.Compared with this,the C group composite invented in this study had higher removal rates of NH₃ and H₂S.It showed that the group C compound preparation had the best deodorization effect on swine manure.In summary,the deodorizing bacteria screened in this study have an efficient deodorizing ability,and can increase the transparency of the manure water.The deodorizing effect of the prepared compound bacteria preparation is obvious,and the release of odor gases?NH₃ and H₂S?from the swine manure can be effectively suppressed.It has a good application prospect in the management of odor gas pollution in scaled livestock and poultry breeding industry.