Comparison of release and transport of manure-borne Escherichia coli and enterococci under grass buffer conditions

Abstract

Aim: To test the hypothesis that Escherichia coli and enterococci bacteria have similar release rates and transport characteristics after being released from land‐applied manure. Methods and Results: Turfgrass soil sod was placed into 200 cm long boxes that had the top two 25 cm sections separated to monitor the release and infiltration of bacteria, which affected bacteria transport in the rest of the box. Dairy manure with added KBr was broadcast on the top two sections. Boxes with either live or dead grass stand were placed under a rainfall simulator for 90 min. Runoff and infiltration samples were collected and analysed for Br, E. coli, enterococci and turbidity. Significant differences in release kinetics of E. coli and enterococci were found. A change from first‐order release kinetics to zero‐order kinetics after 1 h of rainfall simulation was observed. Conclusion: Differences in release rates but not in the subsequent transport were observed for E. coli and enterococci. Significance and Impact of the Study: Because both E. coli and enterococci are currently used as indicator organisms for manure‐borne pathogens, the differences in their release rates may affect the efficiency of using these organisms as indicators.

Estimated human health risks from recreational exposures to stormwater runoff containing animal faecal material

“…Because experiments were analyzed to generate mobilisation fractions (not loads), we assumed that spiking manure samples prior to application did not unduly bias results, although it is possible that high densities of organisms in manure matrices may have a higher proportion of loosely-attached (and more readily-mobilised) organisms than manures with only native organisms. Previous experiments targeting microbial transport from land-applied manure have focused on the behaviour of FIB from cattle manure and produced limited pathogen information (Collins et al, 2004(Collins et al, , 2005Ferguson et al, 2007;Guber et al, 2006Guber et al, , 2007Guber et al, , 2011Guber et al, , 2013Muirhead et al, 2006;Sinton et al, 2007). A recent field rainfall simulation study for land applied pig lagoon effluent also supported the validity of our use of E. coli as a useful surrogate for mobilization of manureassociated Salmonella (Cardoso et al, 2012).…”

Leaching of Cryptosporidium parvum Oocysts, Escherichia coli, and a Salmonella enterica Serovar Typhimurium Bacteriophage through Intact Soil Cores following Surface Application and Injection of Slurry

“…This could indicate the presence of a mixture of planktonic cells as well as cells attached to slurry particles and a subsequent slow detachment of a fraction of these microorganisms into the leachate. Guber et al (33) concluded based on the kinetic release of indigenous E. coli that E. coli also resided in the liquid part of the manure and was released as the liquid manure fraction was diluted and replaced by rainwater. In addition, the presence of manure colloids reduced the attachment of bacterial cells to clay and silt particles, leading to free-cell transport of manure-borne fecal coliforms (34).…”

Escherichia coli Survival in, and Release from, White-Tailed Deer Feces

“…The effect of manure age in artificial cowpats was further studied by Thelin and Gifford (35), Kress and Gifford (36), and Muirhead et al (37), whose results indicated that numbers of released bacterial cells correlated with declining bacterial concentrations in cowpats due to die-off. Additional experiments on kinetics of bacterial release from cattle manure reported differences in release kinetics for different manure components (38)(39)(40) and revealed the effects of manure type, temperature, and solution salinity on the release kinetics (41,42). These experiments also provided parameters for the event-based model KINEROS2/STWIR (43)(44)(45), which predicts overland transport of bacteria released from fecal deposits or surface-applied manure.…”