TITLE:
Antimicrobial Resistance Genes in Animal Manure, Manure-Amended and Nonanthropogenically Impacted Soils in Spain
AUTHORS:
Fernando Esperón, Carlos Sacristán, Matilde Carballo, Ana de la Torre
KEYWORDS:
Antibiotic Resistance, blaCTX-M, mecA, Pig Slurry, vanA
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.9 No.9,
September
21,
2018
ABSTRACT: Environmental dissemination of antimicrobial
resistance genes may occur through agricultural residues, such as animal
manure. We studied the resistome of 16 pool samples of animal manure (pig
slurry [n = 8] and poultry manure [n = 8]), and 16 soil samples (manure-amended
[n = 8] and nonmanure-amended [n = 8]). All samples were collected in central
Spain. Detection was based on 18 selected antimicrobial resistance genes
(ARGs). The most commonly detected genes in animal manure were sul1 (16/16), sul2 (16/16), tet(A)
(16/16), aadA (16/16), tet(B)
(15/16), and str (15/16). Genes blaTEM (7/8), mecA (6/8), vanA (5/8) and qnrB (4/8)
were more frequently detected in chicken manure, whereas pig slurry samples
presented higher levels of tet(C) (8/8) and tet(M) (8/8). Out of the
four genes selected for their clinical relevance, three—blaCTX-M, vanA,
and mecA—were detected in animal
manure. The blaCTX-M (1/8)
and vanA (5/8) genes were only
identified in chicken manure. To our knowledge, this is the first report of
direct detection of mecA gene in
poultry manure and pig slurry. Eleven out of 18 ARGs were detected in amended
soil, while only genes sul2 (3/8) and str (2/8) were found in
nonanthropogenically impacted soils (NAIS), supporting the hypothesis that ARGs
may serve as indicators of “anthropogenic impact” on the environment.