Fate and Transport of Antibiotic Residues and Antibiotic Resistance Genes following Land Application of Manure Waste

Abstract

Antibiotics are used in animal livestock production for therapeutic treatment of disease and at subtherapeutic levels for growth promotion and improvement of feed efficiency. It is estimated that approximately 75% of antibiotics are not absorbed by animals and are excreted in waste. Antibiotic resistance selection occurs among gastrointestinal bacteria, which are also excreted in manure and stored in waste holding systems. Land application of animal waste is a common disposal method used in the United States and is a means for environmental entry of both antibiotics and genetic resistance determinants. Concerns for bacterial resistance gene selection and dissemination of resistance genes have prompted interest about the concentrations and biological activity of drug residues and break-down metabolites, and their fate and transport. Fecal bacteria can survive for weeks to months in the environment, depending on species and temperature, however, genetic elements can persist regardless of cell viability. Phylogenetic analyses indicate antibiotic resistance genes have evolved, although some genes have been maintained in bacteria before the modern antibiotic era. Quantitative measurements of drug residues and levels of resistance genes are needed, in addition to understanding the environmental mechanisms of genetic selection, gene acquisition, and the spatiotemporal dynamics of these resistance genes and their bacterial hosts. This review article discusses an accumulation of findings that address aspects of the fate, transport, and persistence of antibiotics and antibiotic resistance genes in natural environments, with emphasis on mechanisms pertaining to soil environments following land application of animal waste effluent.

Antibiotic resistance genes in manure-amended soil and vegetables at harvest

“…In addition, heavy metals were also detected in manure-amended soil, which might further enhance the dissemination of antibiotic resistance by co-selection with antibiotics, as observed for copper and zinc [31,32]. Long-term and cumulative inputs of antibiotics and heavy metals and their presence can potentially affect the acquisition and maintenance of ARGs in the environment [11,33].…”

Occurrence and distribution of antibiotics in urban soil in Beijing and Shanghai, China

“…After mixing and aging for 24 h (Schlusener et al 2003), the soil samples were extracted with 15 mL of the mixture of acetonitrile and EDTA-McIlvaine buffer (pH 4.0) (2:1) in the presence of ultrasonic treatment, and then (Zorita et al 2009) b (Babić et al 2007) c (Feitosafelizzola and Chiron 2009) d (Park and Choi 2008) e (Sanderson and Thomsen 2009) f (Tolls 2001) g (Lutzhoft et al 1999) h (Diaz-Cruz et al 2006) i (Kan and Petz 2000) j (Jacobsen et al 2004) k l (Kim and Tanaka 2009) m (Calza et al 2009) n (Skinner and Kanfer 1992) p (Chee-Sanford et al 2009) q (Suárez et al 2008) Group Analytes Molecular weight…”

Fate and transport of tylosin-resistant bacteria and macrolide resistance genes in artificially drained agricultural fields receiving swine manure

“…Additionally, Chen et al (2007) identified genes conferring erythromycin (erm) and tetracycline (tet) resistance persisting in swine manure post biofilter treatment. Prior studies have identified elevated levels of antibiotics, antibioticresistant bacteria and antibiotic resistance genes in ground and surface water surrounding confined animal feeding operations (Campagnolo et al, 2002;Chee-Sanford et al, 2009;Heuer et al, 2011). The potential for antibiotics, antibiotic-resistant bacteria and antibiotic-resistance genes leaching into the environment is becoming of greater concern, with approximately 9.2 million hectares of farmland receiving manure annually (Dolliver and Gupta, 2007).…”