Collaborative Research: Quantifying and Correlating Pathogens and a Poultry Feces Marker Gene in Environmental Waters

根据《清洁水法》第303(d)条，美国有10,000个水体因粪便污染而受损，粪便指示细菌证明了这一点。农业实践，包括每年大约16亿公斤的家禽垃圾（被污染的床上用品）作为肥料的土地扩张，是2008年美国水质受损的主要可能来源。家禽垃圾（被粪便污染的床上用品）含有病原体，在暴风雨期间，当土地养殖家禽的成分流失时，病原体会影响环境水。水质退化导致监管行动（损害）、富营养化、生态系统结构改变，以及由于有计划地使用（在某些情况下管理不善）家禽粪便作为肥料而导致鱼类死亡。微生物源跟踪方法可以更准确地确定水体损害的来源，规避以粪便指示菌为基础的病原体监测和粪便污染源识别的已知问题和不足。在接受水的动物粪便中检测到特定的微生物，也就是一种标记物，通过允许流域管理者调查和修复最可能的粪便污染源，加强了环境管理。开发和验证快速方法，以最终确定土地应用的家禽粪便是否在径流中，是美国流域管理的关键需求。这些方法被监管机构和其他关注水质的机构广泛寻求，海滩建议/关闭，TMDL制定，以及污染水道的修复。本研究将批判性地评估1)家禽窝落物标记基因与来自家禽粪便和窝落物的病原体和粪便指示菌的相关性；2)标记基因与人类病原体在环境相关条件下的命运、运输和失活。具体研究将确定鸡窝相关病原体、粪便指示菌和由短杆菌sp. LA35的16S rRNA基因衍生的鸡窝标志物的相关性和存活率。这些研究将在被污染的家禽垃圾和粪便中进行，在模拟环境暴露的实验室中进行，并在实地规模上进行模拟降雨径流研究。在本项目完成时，研究将严格评估禽窝标记基因作为识别水体中禽窝污染的工具的价值，以及该标记在评估暴露于含有禽窝及其相关病原体的水中对人类的风险方面的效用。预计完成的研究将对监测水体中家禽垃圾污染和来自家禽垃圾污染径流的人类病原体的有效性产生重大积极影响。这项研究将导致开发一种工具，使其能够精确测量和模拟来自土地使用的家禽粪便的非点源污染，包括更好地估计这种污染对人类健康的风险。从长远来看，这项研究将为水质管理者提供一种快速定量的工具，用于识别污染源和确定适当的家禽垃圾在农田中的施用率，最终通过家禽垃圾管理降低公众对人类病原体的暴露。

1234366/1234237Weidhaas/HarwoodOver 10,000 US water bodies are impaired under section 303(d) of the Clean Water Act due to fecal contamination, as evidenced by fecal indicator bacteria. Agricultural practices, including land spreading of approximately 1.6 billion kg of poultry litter (soiled bedding) per year as a fertilizer, were the leading probable source of water quality impairments in the US in 2008. Poultry litter (bedding contaminated with feces) contains pathogens which can impact environmental waters when constituents of land-applied poultry run off during storms. Degraded water quality leads to regulatory action (impairment), eutrophication, altered ecosystem structure, and fish kills due to the planned application, and in some cases mismanagement, of poultry litter as a fertilizer. Microbial source tracking methods can be used to more accurately determine the source of impairment to water bodies, and to circumvent known issues and inadequacies in fecal indicator bacteria-based pathogen monitoring and fecal pollution source identification. Detection of microorganisms specific to one animal's feces, a.k.a. a marker, in receiving water enhances environmental stewardship by allowing watershed managers to investigate and remediate only the most likely sources of fecal pollution. Development and validation of rapid methods to conclusively determine whether land-applied poultry litter is in runoff is a crucial need for watershed management across the U.S. These methods are widely sought by regulatory agencies and others concerned with water quality beach advisories/closures, TMDL formulation, and remediation of contaminated waterways. This research will critically evaluate 1) a poultry litter marker gene's correlation with pathogens and fecal indicator bacteria originating from poultry feces and litter and 2) the fate, transport and inactivation of the marker gene and human pathogens under environmentally relevant conditions. Specific studies will be conducted to determine the correlation and survival of poultry litter associated pathogens, fecal indicator bacteria, and the poultry litter marker derived from the 16S rRNA gene of Brevibacterium sp. LA35. These studies will be conducted in soiled poultry litter and feces, in laboratory mesocosms simulating environmental exposure, and in field-scale, simulated rainfall runoff studies. At the completion of this project the research will have critically evaluated the value of the poultry litter marker gene as a tool to identify poultry litter contamination in water bodies, as well as the marker's utility in assessing risk to humans from exposure to water containing poultry litter and its associated pathogens.The completed study is expected to have a significant positive impact on the efficacy of monitoring of water bodies for poultry litter contamination and human pathogens originating from runoff contaminated by poultry litter. This research will lead to the development of a tool that allows accurate measurement and modeling of non-point source pollution from land-applied poultry litter, including better estimates of human health risk from such contamination. In the long term, this research will provide water quality managers with a rapid and quantitative tool for identifying pollution sources and for determining appropriate poultry litter application rates to agricultural fields, which will ultimately lead to lower public exposure to human pathogens as a result of poultry litter management.