肉鸭发酵床抗生素、重金属累积及细菌耐药性的演变特性

Accumulation of antibiotics， heavy metals and antimicrobial-resistant bacteria in duck bio-bed

摘要:

摘要:【目的】了解肉鸭发酵床使用过程中抗生素、各类金属元素累积特性，细菌抗生素耐受性演变特性。【方法】2011年11月至2013年7月，江苏某肉鸭发酵床养殖场饲养肉鸭期间，选取刚制作完成发酵床的鸭舍，和饲养4批次、8批次肉鸭时的鸭舍，检测发酵床中抗生素、金属元素含量，及发酵床中细菌的抗生素耐受水平。【结果】肉鸭发酵床垫料内强力霉素残留量因每批次肉鸭饲料中的使用而显著上升，氧氟沙星未现在垫料内累积。发酵床垫料饲养至8批次肉鸭时，垫料内耐受16、100 μg/mL强力霉素三种可培养细菌的平均菌落数与比例为最高，而耐受8、50 μg/mL 氧氟沙星的平均菌落数、菌落数比例未现明显的增长趋势。发酵床使用过程中，垫料内As、Pb、Hg元素含量未显著增加，Cd元素检测量极低，Zn、Mn元素含量增加趋势明显，Cu、Cr元素累积速度缓慢。【结论】每批次使用强力霉素可在多批次肉鸭饲养后显著增加发酵床垫料中强力霉素含量，显著增强垫料中肠道菌群耐受强力霉素能力，Zn、Mn元素含量总体呈上升趋势。

关键词:关键词:发酵床，抗生素，金属，耐药，累积

Abstract:

Abstract:［Objective］The objective of this study is to understand the accumulation of antibiotics，metals in the litter，and evolution features of bacterial antimicrobial-resistance during the fermentation of duck bio-bed.［Methods］ The experiment was conducted in meat duck bio-bed farm of Jiangsu province from November 2011 to July 2013. The new litter and spent litter from 4th，8th meat duck flock were studied for the accumulation of consumed antimicrobials and metals．Bacterial resistance levels to consumed antimicrobials were measured in the collected litter.［Results］The residues of doxycycline in the litter increased significantly after successive flocks of meat ducks，but ofloxacin had not been detected in all litter samples. The litter for the 8th meat duck flock had the highest level of resistant cultivable bacteria in the three sorts of medium amended with 16 μg/mL，100 μg/mL doxycycline．Meanwhile，the level of resistant cultivable bacteria in the same sort of medium amended with 8 μg/mL，50 μg/mL ofloxacin differed insignificantly between different flock litter sample． Different flock litter differed insignificantly in the accumulation content of As，Pb and Hg，and was low in Cd．The 4th，8th flock litter increased significantly in Zn and Mn than new litter，and increased slowly in Cu and Cr.［Conclusion］With the application of doxycycline in each flock of meat ducks，the content of doxycycline and doxycycline resistance in enterobacteriaceae bacteria in the litter increased significantly，Zn and Mn had an increasing trend overall.

Key words:Keywords: bio-bed，antibiotic，metal，antimicrobial-resistant，accumulation