scholarly journals Grazing Effects on Bovine-Associated and Background Fecal Indicator Bacteria Levels in Edge-of-Field Runoff

Water ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 928
Author(s):  
Kevin L. Wagner ◽  
Terry J. Gentry ◽  
R. Daren Harmel ◽  
Emily C. Pope ◽  
Larry A. Redmon
Keyword(s):  
Water Quality ◽  
Fecal Indicator Bacteria ◽  
Grazing Management ◽  
Indicator Bacteria ◽  
Watershed Scale ◽  
Stocking Rate ◽  
Small Watershed ◽  
Fecal Indicator ◽  
E Coli ◽  
Runoff Events

Excessive levels of fecal indicator bacteria are a major cause of water quality impairment. Grazing and its management may significantly impact bacteria concentrations; however, other sources can contribute to water quality issues both in the presence and absence of cattle, thus confounding results. In this study, we utilize Bacteroides markers to evaluate bacteria loading from cattle versus background sources in runoff from rotationally grazed and ungrazed pastures and how grazing management, timing of runoff in relation to grazing events, and stocking rate affect Bacteroides marker (AllBac and BoBac) levels and ratios and their relation to E. coli concentrations in runoff at the small watershed scale. The data suggest that the AllBac and BoBac levels were not significantly impacted by grazing management or stocking rate; however, the timing of runoff events in relation to grazing events significantly impacted the levels of these markers found in runoff. Furthermore, the BoBac/AllBac ratio confirmed that fecal contamination present in runoff when sites were destocked for over two weeks largely originated from sources other than cattle. Thus, the magnitude and proportion of cattle impacts on fecal indicator bacteria in edge-of-field runoff were dramatically reduced shortly after de-stocking. However, background sources continued to contribute significant concentrations of E. coli.

scholarly journals Decay of Fecal Indicator Bacterial Populations and Bovine-Associated Source-Tracking Markers in Freshly Deposited Cow Pats

2013 ◽  
Vol 80 (1) ◽  
pp. 110-118 ◽  
Author(s):  
Adelumola Oladeinde ◽  
Thomas Bohrmann ◽  
Kelvin Wong ◽  
S. T. Purucker ◽  
Ken Bradshaw ◽  
...  
Keyword(s):  
Decay Rate ◽  
Fecal Indicator Bacteria ◽  
Decay Rates ◽  
Indicator Bacteria ◽  
Source Tracking ◽  
Fecal Indicator ◽  
Bacterial Populations ◽  
Content Type ◽  
E Coli ◽  
Decay Dynamic

ABSTRACTUnderstanding the survival of fecal indicator bacteria (FIB) and microbial source-tracking (MST) markers is critical to developing pathogen fate and transport models. Although pathogen survival in water microcosms and manure-amended soils is well documented, little is known about their survival in intact cow pats deposited on pastures. We conducted a study to determine decay rates of fecal indicator bacteria (Escherichia coliand enterococci) and bovine-associated MST markers (CowM3, Rum-2-bac, and GenBac) in 18 freshly deposited cattle feces from three farms in northern Georgia. Samples were randomly assigned to shaded or unshaded treatment in order to determine the effects of sunlight, moisture, and temperature on decay rates. A general linear model (GLM) framework was used to determine decay rates. Shading significantly decreased the decay rate of theE. colipopulation (P< 0.0001), with a rate of −0.176 day−1for the shaded treatment and −0.297 day−1for the unshaded treatment. Shading had no significant effect on decay rates of enterococci, CowM3, Rum-2-bac, and GenBac (P> 0.05). In addition,E. colipopulations showed a significant growth rate (0.881 day−1) in the unshaded samples during the first 5 days after deposition. UV-B was the most important parameter explaining the decay rate ofE. colipopulations. A comparison of the decay behaviors among all markers indicated that enterococcus concentrations exhibit a better correlation with the MST markers thanE. coliconcentrations. Our results indicate that bovine-associated MST markers can survive in cow pats for at least 1 month after excretion, and although their decay dynamic differs from the decay dynamic ofE. colipopulations, they seem to be reliable markers to use in combination with enterococci to monitor fecal pollution from pasture lands.

scholarly journals Poikilothermic Animals as a Previously Unrecognized Source of Fecal Indicator Bacteria in a Backwater Ecosystem of a Large River

2018 ◽  
Vol 84 (16) ◽  
Author(s):  
Christina Frick ◽  
Julia Vierheilig ◽  
Rita Linke ◽  
Domenico Savio ◽  
Horst Zornig ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Clostridium Perfringens ◽  
Fecal Indicator Bacteria ◽  
Indicator Bacteria ◽  
Primary Sources ◽  
Fecal Indicator ◽  
Content Type ◽  
E Coli ◽  
High Concentrations ◽  
Intestinal Enterococci

ABSTRACTQuantitative information regarding the presence ofEscherichia coli, intestinal enterococci, andClostridium perfringensin poikilotherms is notably scarce. Therefore, this study was designed to allow a systematic comparison of the occurrence of these standard fecal indicator bacteria (SFIB) in the excreta of wild homeothermic (ruminants, boars, carnivores, and birds) and poikilothermic (earthworms, gastropods, frogs, and fish) animals inhabiting an alluvial backwater area in eastern Austria. With the exception of earthworms, the average concentrations ofE. coliand enterococci in the excreta of poikilotherms were equal to or only slightly lower than those observed in homeothermic excreta and were 1 to 4 orders of magnitude higher than the levels observed in the ambient soils and sediments. Enterococci reached extraordinarily high concentrations in gastropods. Additional estimates of the daily excreted SFIB (E. coliand enterococcus) loads (DESL) further supported the importance of poikilotherms as potential pollution sources. The newly established DESL metric also allowed comparison to the standing stock of SFIB in the sediment and soil of the investigated area. In agreement with its biological characteristics, the highest concentrations ofC. perfringenswere observed in carnivores. In conclusion, the long-standing hypothesis that only humans and homeothermic animals are primary sources of SFIB is challenged by the results of this study. It may be necessary to extend the fecal indicator concept by additionally considering poikilotherms as potential important primary habitats of SFIB. Further studies in other geographical areas are needed to evaluate the general significance of our results. We hypothesize that the importance of poikilotherms as sources of SFIB is strongly correlated with the ambient temperature and would therefore be of increased significance in subtropical and tropical habitats and water resources.IMPORTANCEThe current fecal indicator concept is based on the assumption that the standard fecal indicator bacteria (SFIB)Escherichia coli, intestinal enterococci, andClostridium perfringensmultiply significantly only in the guts of humans and other homeothermic animals and can therefore indicate fecal pollution and the potential presence of pathogens from those groups. The findings of the present study showed that SFIB can also occur in high concentrations in poikilothermic animals (i.e., animals with body temperatures that vary with the ambient environmental temperature, such as fish, frogs, and snails) in an alluvial backwater area in a temperate region, indicating that a reconsideration of this long-standing indicator paradigm is needed. This study suggests that poikilotherms must be considered to be potential primary sources of SFIB in future studies.

scholarly journals Comparison of the Multiple-Sample Means with Composite Sample Results for Fecal Indicator Bacteria by Quantitative PCR and Culture

2012 ◽  
Vol 78 (19) ◽  
pp. 7166-7169 ◽  
Author(s):  
Reagan R. Converse ◽  
Larry J. Wymer ◽  
Alfred P. Dufour ◽  
Timothy J. Wade
Keyword(s):  
Water Quality ◽  
Quantitative Pcr ◽  
Fecal Indicator Bacteria ◽  
Water Quality Monitoring ◽  
Indicator Bacteria ◽  
Quality Monitoring ◽  
Composite Sample ◽  
Fecal Indicator ◽  
Composite Sampling ◽  
Multiple Sample

ABSTRACTFew studies have addressed the efficacy of composite sampling for measuring indicator bacteria by quantitative PCR (qPCR). We compared results from composited samples with multiple-sample means for culture- and qPCR-based water quality monitoring. Results from composited samples for both methods were similarly correlated to multiple-sample means and predicted criteria exceedances equally.

scholarly journals Systematic review of predictive models of microbial water quality at freshwater recreational beaches

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256785
Author(s):  
Cole Heasley ◽  
J. Johanna Sanchez ◽  
Jordan Tustin ◽  
Ian Young
Keyword(s):  
Systematic Review ◽  
Water Quality ◽  
Predictive Models ◽  
Fecal Indicator Bacteria ◽  
Grey Literature ◽  
Predictive Modelling ◽  
The United States ◽  
Risk Of Bias ◽  
Indicator Bacteria ◽  
Fecal Indicator

Monitoring of fecal indicator bacteria at recreational waters is an important public health measure to minimize water-borne disease, however traditional culture methods for quantifying bacteria can take 18–24 hours to obtain a result. To support real-time notifications of water quality, models using environmental variables have been created to predict indicator bacteria levels on the day of sampling. We conducted a systematic review of predictive models of fecal indicator bacteria at freshwater recreational sites in temperate climates to identify and describe the existing approaches, trends, and their performance to inform beach water management policies. We conducted a comprehensive search strategy, including five databases and grey literature, screened abstracts for relevance, and extracted data using structured forms. Data were descriptively summarized. A total of 53 relevant studies were identified. Most studies (n = 44, 83%) were conducted in the United States and evaluated water quality using E. coli as fecal indicator bacteria (n = 46, 87%). Studies were primarily conducted in lakes (n = 40, 75%) compared to rivers (n = 13, 25%). The most commonly reported predictive model-building method was multiple linear regression (n = 37, 70%). Frequently used predictors in best-fitting models included rainfall (n = 39, 74%), turbidity (n = 31, 58%), wave height (n = 24, 45%), and wind speed and direction (n = 25, 47%, and n = 23, 43%, respectively). Of the 19 (36%) studies that measured accuracy, predictive models averaged an 81.0% accuracy, and all but one were more accurate than traditional methods. Limitations identifed by risk-of-bias assessment included not validating models (n = 21, 40%), limited reporting of whether modelling assumptions were met (n = 40, 75%), and lack of reporting on handling of missing data (n = 37, 70%). Additional research is warranted on the utility and accuracy of more advanced predictive modelling methods, such as Bayesian networks and artificial neural networks, which were investigated in comparatively fewer studies and creating risk of bias tools for non-medical predictive modelling.

scholarly journals Fecal Indicator Bacteria Transport from Watersheds with Differing Wastewater Technologies and Septic System Densities

2020 ◽  
Vol 10 (18) ◽  
pp. 6525
Author(s):  
Guy Iverson ◽  
Christa Sanderford ◽  
Charles P. Humphrey ◽  
J. Randall Etheridge ◽  
Timothy Kelley
Keyword(s):  
Wastewater Treatment ◽  
Fecal Indicator Bacteria ◽  
Indicator Bacteria ◽  
Septic Systems ◽  
Watershed Scale ◽  
Septic System ◽  
Treatment Technology ◽  
Fecal Indicator ◽  
Bacteria Transport ◽  
Density Threshold

Wastewater contains elevated concentrations of fecal indicator bacteria (FIB). The type of wastewater treatment technology and septic system density may influence the FIB concentration and exports at the watershed scale. The goal of this study was to gain a better understanding of FIB concentrations and exports from watersheds served by conventional septic (CS) systems, sand filter (SF) septic systems, and a municipal sewer (SEW) system. Seven watersheds (3 CS, 3 SF, and 1 SEW) were monitored to quantify FIB concentration and export monthly from April 2015 to March 2016. The type of wastewater treatment did not yield significant differences in FIB concentration or exports when pooling watersheds using similar wastewater treatment. Watersheds with the highest septic densities (approximately 0.4 systems ha−1) contained greater FIB concentrations and exports than watersheds with the lowest (approximately 0.1–0.2 systems ha−1), but only FIB concentrations significantly differed. These findings suggest that when the septic system density exceeds 0.4 systems ha−1, water quality degradation from septic leachate may be observable at the watershed scale, especially in watersheds dominated by residential development. More research is recommended to determine if this density threshold is similar for other water pollutants and/or in watersheds with differing hydrogeological, land use, and wastewater characteristics.

scholarly journals Springing for Safe Water: Drinking Water Quality and Source Selection in Central Appalachian Communities

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 888 ◽  
Author(s):  
Hannah Patton ◽  
Leigh-Anne Krometis ◽  
Emily Sarver
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Tap Water ◽  
Fecal Indicator Bacteria ◽  
The United States ◽  
Spring Water ◽  
Indicator Bacteria ◽  
Drinking Water Source ◽  
Fecal Indicator ◽  
Source Selection

Issues surrounding water infrastructure, access, and quality are well documented in the Central Appalachian region of the United States. Even in cases where residents have in-home piped point-of-use (POU) water, some rely on alternative drinking water sources for daily needs—including water collection from roadside springs. This effort aims to better understand and document spring usage in this region by identifying the factors that influence drinking water source selection and comparing household and spring water quality to Safe Drinking Water Act (SDWA) health-based and aesthetic contaminant recommendations. Households were recruited from communities surrounding known springs in three states (Kentucky, Virginia, and West Virginia). First- and second-draw, in-home POU tap water samples were collected from participating households and compared to samples collected from local springs on the same day. Samples were analyzed for fecal indicator bacteria and inorganic ions. Study participants completed surveys to document perceptions of household drinking water and typical usage. The majority of survey participants (82.6%) did not trust their home tap water due to aesthetic issues. Water quality results suggested that fecal indicator bacteria were more common in spring water, while several metallic ions were recovered in higher concentrations from household samples. These observations highlight that health risks and perceptions may be different between sources.

scholarly journals Test of Direct and Indirect Effects of Agrochemicals on the Survival of Fecal Indicator Bacteria

2011 ◽  
Vol 77 (24) ◽  
pp. 8765-8774 ◽  
Author(s):  
Zachery R. Staley ◽  
Jason R. Rohr ◽  
Valerie J. Harwood
Keyword(s):  
Water Column ◽  
Indirect Effects ◽  
Fecal Indicator Bacteria ◽  
Water Bodies ◽  
Indicator Bacteria ◽  
Inorganic Fertilizer ◽  
Direct Effects ◽  
Fecal Indicator ◽  
Content Type ◽  
E Coli

ABSTRACTWater bodies often receive agrochemicals and animal waste carrying fecal indicator bacteria (FIB) and zoonotic pathogens, but we know little about the effects of agrochemicals on these microbes. We assessed the direct effects of the pesticides atrazine, malathion, and chlorothalonil and inorganic fertilizer onEscherichia coliand enterococcal survival in simplified microcosms held in the dark.E. colistrain composition in sediments and water column were positively correlated, but none of the agrochemicals had significant direct effects onE. colistrain composition or on densities of culturable FIBs. In a companion study, microcosms with nondisinfected pond water and sediments were exposed to or shielded from sunlight to examine the potential indirect effects of atrazine and inorganic fertilizer onE. coli. The herbicide atrazine had no effect onE. coliin dark-exposed microcosms containing natural microbial and algal communities. However, in light-exposed microcosms, atrazine significantly loweredE. colidensities in the water column and significantly increased densities in the sediment compared to controls. This effect appears to be mediated by the effects of atrazine on algae, given that atrazine significantly reduced phytoplankton, which was a positive and negative predictor ofE. colidensities in the water column and sediment, respectively. These data suggest that atrazine does not directly affect the survival of FIB, rather that it indirectly alters the distribution and abundance ofE. coliby altering phytoplankton and periphyton communities. These results improve our understanding of the influence of agricultural practices on FIB densities in water bodies impacted by agricultural runoff.

Sign in / Sign up

Export Citation Format

Share Document