tet and sul Antibiotic Resistance Genes in Livestock Lagoons of Various Operation Type, Configuration, and Antibiotic Occurrence

Abstract

Although livestock operations are known to harbor elevated levels of antibiotic resistant bacteria, few studies have examined the potential of livestock waste lagoons to reduce antibiotic resistance genes (ARGs). The purpose of this study was to determine the prevalence and examine the behavior of tetracycline [tet(O) and tet(W)] and sulfonamide [sul(I) and sul(II)] ARGs in a broad cross-section of livestock lagoons within the same semiarid western watershed. ARGs were monitored for one year in the water and the settled solids of eight lagoon systems by quantitative polymerase chain reaction. In addition, antibiotic residues and various bulk water quality constituents were analyzed. It was found that the lagoons of the chicken layer operation had the lowest concentrations of both tet and sul ARGs and low total antibiotic concentrations, whereas sul ARGs were highest in the swine lagoons, which generally corresponded to the highest total antibiotic concentrations. A marginal benefit of organic and small dairy operations also was observed compared to conventional and large dairies, respectively. In all lagoons, sul ARGs were observed to be generally more recalcitrant than tet ARGs. Also, positive correlations of various bulk water quality constituents were identified with tet ARGs but not sul ARGs. Significant positive correlations were identified between several metals and tet ARGs, but Pearson's correlation coefficients were mostly lower than those determined between antibiotic residues and ARGs. This study represents a quantitative characterization of ARGs in lagoons across a variety of livestock operations and provides insight into potential options for managing antibiotic resistance emanating from agricultural activities.

Dissemination of veterinary antibiotics and corresponding resistance genes from a concentrated swine feedlot along the waste treatment paths

“…6b), while the correlation between the total TRGs and the total TCs was not significant. Similar results have been reported by previous studies (Gao et al, 2012;Luo et al, 2010;Mckinney et al, 2010;Peak et al, 2007). It is seen that the relatively high water solubility and stability of SAs tend to promote the spread of antibiotic resistance and also contribute to the strong correlation between SRGs and SAs in the aquatic environment (CheeSanford et al, 2009).…”

“…In the fertilized soil (S2) and unfertilized soil (S3), the relative abundances of target ARGs were in the ranges of 2.86 × 10 (Table S6). This seasonal variation of ARGs was also reported by other studies (Mckinney et al, 2010;Yang et al, 2013), implying that low temperatures favored the maintenance of ARGs. Nevertheless, in the downstream lagoon wastewater (W3), all ARGs were less abundant in winter.…”

“…The presence of residual antibiotics could enhance the resistance level of microbial communities and promote the proliferation of antibiotic resistance genes (ARGs) in swine manure (Looft et al, 2012), livestock and poultry wastewater (Mckinney et al, 2010;Peak et al, 2007), farmland soil (Huang et al, 2013;Wu et al, 2010), and surface water (Graham et al, 2010;Luo et al, 2010). The residual antibiotics could promote the accumulation of ARGs even at subtherapeutic levels (Ghosh and Lapara, 2007).…”

Emerging organic contaminants in groundwater: A review of sources, fate and occurrence

“…Kolpin et al, 2000, Lapworth et al, 2006 and reinforces the need to monitor and regulate for degradates of EOCs as well as their parent compounds. A related area requiring continued research is the effect of antibiotics on microbes and the development of antibiotic-resistant bacteria in the subsurface, for example under waste lagoons (Pruden et al, 2006, Mckinney et al, 2010 and their effects on soil microbial communities (Gutierrez et al, 2010 …”

Effects of electron acceptors on removal of antibiotic resistant Escherichia coli, resistance genes and class 1 integrons under anaerobic conditions

“…ARGs are therefore considered the primary contaminants of interest in minimizing the potential to spread antibiotic resistance . The persistence and selective increase of ARGs resulting from horizontal gene transfer is a major challenge for biological treatment processes (McKinney et al, 2010;Miller et al, 2016). The slopes in Fig.…”