Composting of chicken litter from commercial broiler farms reduces the abundance of viable enteric bacteria, Firmicutes, and selected antibiotic resistance genes

被引：34

作者：

Subirats, Jessica ^{[1
,2
]}

Murray, Roger ^{[1
]}

Scott, Andrew ^{[1
]}

Lau, Calvin Ho-Fung ^{[3
]}

Topp, Edward ^{[1
,2
]}

机构：

[1] Agr & Agri Food Canada, London Res & Dev Ctr, 1391 Sandford St, London, ON N5V 4T3, Canada

[2] Univ Western Ontario, Dept Biol, London, ON, Canada

[3] Canadian Food Inspect Agcy, 960 Carling Ave, Ottawa, ON, Canada

来源：

SCIENCE OF THE TOTAL ENVIRONMENT | 2020年 / 746卷

关键词：

Composting; Antibiotic resistance; Chicken litter; Bacterial community; DAIRY MANURE; SWINE MANURE; SOIL; PERSISTENCE; RESISTOME; COMMUNITIES; VEGETABLES; DIVERSITY; SLUDGE; FATE;

D O I：

10.1016/j.scitotenv.2020.141113

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

We examined the ability of composting to remove ARGs and enteric bacteria in litter obtained from broiler chickens fed with a diet supplemented with Bacitracin methylene disalicylate (BDM) (conventional chicken litter), or an antibiotic-free diet (raised without antibiotic (RWA) chicken litter). This was done by evaluating the litter before and after composting for the abundance of ten gene targets associated with antibiotic resistance or horizontal gene transfer, the composition of the bacterial communities, and the abundance of viable enteric bacteria. The abundance of gene targets was determined by qPCR and the microbial community composition of chicken litter determined by 16S rRNA gene amplicon sequencing. Enteric bacteria were enumerated by viable plate count. A majority of the gene targets were more abundant in conventional than in RWA litter. In both litter types, the absolute abundance of all of the target genes decreased after composting except sul1, intI1, incW and erm(F) that remained stable. Composting significantly reduced the abundance of enteric bacteria, including those carrying antibiotic resistance. The major difference in bacterial community composition between conventional and RWA litter was due to members affiliated to the genus Pseudomonas, which were 28% more abundant in conventional than in RWA litter. Composting favoured the presence of thermophilic bacteria, such as those affiliated with the genus Truepera, but decreased the abundance of those bacterial genera associated with cold-adapted species, such as Carnobacterium, Psychrobacter and Oceanisphaera. The present study shows that chicken litter from broilers fed with a diet supplemented with antibiotic has an increased abundance of some ARGs, even after composting. However, we can conclude that fertilization with composted litter represents a reduced risk of transmission of antibiotic resistance genes and enteric bacteria of poultry origin to soil and crops than will fertilization with raw litter. Crown Copyright (C) 2020 Published by Elsevier B.V. All rights reserved.

引用

页数：10