Via Department of Civil and Environmental Engineering, 418 Durham Hall, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.
Environ Sci Technol. 2010 Aug 15;44(16):6102-9. doi: 10.1021/es9038165.
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.
尽管已知家畜养殖场中存在高水平的抗生素耐药细菌，但很少有研究检查家畜废物池降低抗生素耐药基因（ARGs）的潜力。本研究的目的是确定在同一半干旱西部流域的广泛家畜池塘中四环素[tet（O）和 tet（W）]和磺胺类[ sul（I）和 sul（II）]ARGs 的流行情况，并检查其行为。通过定量聚合酶链反应在一年中监测了八个池塘系统的水和沉淀固体中的 ARGs。此外，还分析了抗生素残留和各种水体质量成分。结果发现，鸡层养殖场的池塘中 tet 和 sul ARGs 的浓度最低，抗生素总浓度也最低，而猪养殖场的 sul ARGs 浓度最高，这与抗生素总浓度最高相对应。与传统和大型奶牛场相比，有机和小型奶牛场也观察到了边际效益。在所有池塘中，sul ARGs 的抗降解性通常比 tet ARGs 强。此外，还确定了各种水体质量成分与 tet ARGs 之间存在正相关关系，但与 sul ARGs 无关。确定了几种金属与 tet ARGs 之间存在显著的正相关关系，但皮尔逊相关系数大多低于抗生素残留与 ARGs 之间确定的相关系数。本研究代表了对各种家畜养殖场池塘中 ARGs 的定量特征描述，并为管理农业活动产生的抗生素耐药性提供了潜在的选择。
