Effects Of Veterinary Antibiotics On The Performance During Pig Manure Biogas Fermentation

With the rapid development of animal husbandy,antibiotics are widely used in livestock industry as veterinary medicines and feed additives,it leads to high levels of veterinary antibiotic residues in livestock manure.Biogas fermentation technology can effectually use livestock manure to produce biogas,to realize the innocent treatment and the energy conversion of livestock manure.However,veterinary antibiotics residues in livestock manure is one of the prime reasons for the inefficient operation of biogas fermentation.In the paper,fresh pig manure and corn straw are used as raw material to anaerobic fermentation,add different concentrations of Enrofloxacin and Sulfamethazine to the fermentation tanks respectively,experiment with the simple homemade constant temperature anaerobic fermentation equipment to study the effects of Enrofloxacin or Sulfamethazine on the rate of biogas production,pH,enzyme activities and microbial diversity,as well as,offer the technical support and the theoretical foundation for the innocent treatment oflivestock manure containing Enrofloxacin or Sulfamethazine,and improve the efficiency of the anaerobic fermentation of livestock manure.The main conclusions are as follows:(1)The anaerobic fermentation test's results added with Enrofloxacin show that,during the start-up peried of the anaerobic fermentation,different concentrations of Enrofloxacin have obviously inhibited the cellulase activities and urease activities,20mg·kg-1 Enrofloxacin has promoted the surcrase activities.During the end peried of the anaerobic fermentation,the cellulase activities,urease activities and surcrase activities are very similar in all treatments.In the 5-31d of anaerobic fermentation,Enrofloxacin has obviously inhibiting effects on the rate of biogas production.During the end peried of anaerobic fermentation,the rate of biogas production has little influence from Enrofloxacin's inhibition.At the end of anaerobic fermentation,the total biogas productions added with 20 mg·kg-1,60 mg·kg-1,120 mg·kg-1 Enrofloxacin respectively are the control group's 92.6%,87.8%,84.3%.(2)The anaerobic fermentation test's results added with Sulfamethazine show that,during the start-up peried of the anaerobic fermentation,20 mg·kg-1 Sulfamethazine promotes the urease activities.During the end period,120 mg·kg-1 Sulfamethazine promotes the dehydrogenase activities,at other stages there are no influence on enzyme activities.Sulfamethazine have the same effects on the rate of anaerobic fermentation with Enrofloxacin.The total biogas productions added with 20 mg·kg-1,60 mg·kg-1,120 mg·kg-1 Sulfamethazine respectively are the control group's 91.56%,84.5%,79.52%.(3)Analyze the microbial diversity of anaerobic fermentation added with Enrofloxacin and Sulfamethazine,and measure the AWCD value,Shannon index and Simpson index of every stage.The results show that,in the initial stage of anaerobic fermentation,the veterinary antibiotics have inhibiting effects on microbial diversity.After the fermentation started,the veterinary antibiotics have no obvious effects on the microbial diversity.During the end peried of the anaerobic fermentation,the microbial diversity is more rich in the tests with 60 mg-kg.1,120 mg.kg-1 antibiotics.