Microbial Ecology Research For Degradation Of Tylosin During Pig Manure Composting

Antibiotics are used for the treatment of human diseases,but also are used in the midst of livestock and poultry breeding livestock on a large scale,as a result,it has produced very serious environmental pollution problems.Because all antibiotics are not fully used in the animals,there are plenty of antibiotics through feces or urine and other various ways into the soil,water,and with the use of organic manure,antibiotics will enter to the crops,ultimately through human consumption will enter human body.So it will have incalculable long-term impact on the sustainable development of aquaculture,agriculture and human health.On this test for feces produced by poultry livestock with the exist of tylosin,in the first place two strains with stronger tylosin degradation ability are been isolated in the laboratory,on the basis of this,through the further refine research,the degradation of tylosin features about the two strains of bacteria has been cleared out.Based on previous laboratory research results,in the outdoor tylosin as a mode antibiotic of macrolide antibiotics,through systematic research to explore tylosin degradation and the physical and chemical properties about adding exogenous tylosin degradation microbes in pig manure composting and using high-throughput sequencing at the same time,the pig was studied from the microscopic gene level to research the mechanism of molecular biology.The main results are as follows:(1)Through the tylosin isolating of 17 strains of bacteria library,strains of A and B have highest tylosin degradation rate.In the tylosin degradation characteristics study culture medium concentration,tylosin concentration,temperature,speed,pH,inoculation amountof A and B strains,the optimization tylosin degradation condition is:medium concentration 1/1 MM,tylosin concentration of 50～200 mg·L-1,temperature 30～40℃,rotation speed 150～170 rpm,pH 6～10,inoculation amount 1%.(2)Adding exogenous microbial agents increased the compost of tylosin degradation rate,the compost temperature,moisture content,the change of pH values and other factors are influenced,but also can reduce the toxicity of compost is complete pile body,has a certain promoting role to compost finished completely,with the compost finally finished,the wheat GI value of adding exogenous microbial agents is 95.43%,while the other treatment germination index value were lower than the adding exogenous microbial agents treatment.Adding microbial agents can obviously reduce the loss of nitrogen,promoting nitrogen recycling,after the composte finish,total nitrogen content is decreased by 30.05%,whereas TYL treatment was reduced by 32.14%,CK treatment total nitrogen was reduced by 32.63%.Microbial diversity sequencing results show that the pile body bacteria community diversity relative abundance of the gene level have increased significantly after the compost.The exists of the degradation bacteria about tylosin degradation increased the relative abundance of the bacteria at the high temperature composting period.Bcillus and Pseudogracilibacillus might be have a good regulation effect in the degradation of tylosin.Microorganism,as it were,in a sense is increase the removal efficiency of tylosin in the compost,and it is also reduce the toxicity.