Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
composting systems
(last updated on 4/5/2012)
Avery, L.M., A. P. Williams, K. Killham, and D.L. Jones. 2009. Heat and lime-treatment as effective control methods
for E. coli O157:H7 in organic wastes. Bioresource Technol. 100:2692-2698.
No viable E. coli O157:H7 cells were recovered from ovine abattoir waste (containing 7.2 x 105 CFU/ml waste) when the
waste was heated at 60°C for 10 min or lime (CaO) was applied at a rate of 10 g/L. Temperatures of 72°C induced waste
solidification rendering its use impractical.
Baloda, S.B., L. Christensen, and S. Trajcevska. 2001. Persistence of a Salmonella enterica serovar Typhimurium
DT12 clone in a piggery and in agricultural soil amended with Salmonella-contaminated slurry. Appl. Environ.
Microbiol. 67:2859-2862.
When Salmonella-contaminated slurry was disposed of on the agricultural soil (a common waste disposal practice), the
pathogen was isolated up to 14 days after the spread.
Briancesco, R., A.M. Coccia, G. Chiaretti, L.S. Della, M. Semproni, and L. Bonadonna. 2008. Assessment of
microbiological and parasitological quality of composted wastes: health implications and hygienic measures. Waste
Manag. Res. 26:196-202.
Feedstock and compost samples were collected from 20 composting plants. Compost obtained by feedstock containing
sewage sludge was shown to have a better hygienic quality in comparison with compost containing green discards and
municipal solid waste as raw matter.
Campo, N.C.D., I.L. Pepper, and C.P. Gerba. 2007. Assessment of Salmonella typhimurium growth in Class A
biosolids and soil/biosolid mixtures. J. Residuals Sci. Technol. 4:83-88.
No growth occurred in any of the biosolids with a moisture content of 20%. Growth of Salmonella did occur in all of the
Class A products under saturated conditions.
Cessna, A.J., F.J. Larney, S.L. Kuchta, X. Hao, T. Entz, E. Topp, and T.A. McAllister. 2011. Veterinary
antimicrobials in feedlot manure: Dissipation during composting and effects on composting processes. J. Environ.
Qual. 40:188-198.
The study showed that while composting led to dissipation of antimicrobials, the microbially driven composting process
appeared to be inhibited by their presence.
Ceustermans, A., D. De Clercqu, A. Aertsen, C. Michiels, J. Coosemans, and J. Ryckeboer. 2007. Inactivation of
Salmonella Senftenberg strain W775 during composting of biowastes and garden wastes. J. Appl. Microbiol. 103:5364.
In this study, temperature was the most important parameter affecting survival of Salmonella Senftenberg W775. In addition,
it was indicated that moisture content and the indigenous microbial flora were additional factors that affected survival of the
pathogen. The authors concluded that further research was necessary to determine the extent to which these factors
contribute to eradication.
This article also includes a table documenting the survival times of Salmonella spp. from numerous studies investigating the
composting process and details the time-temperature, moisture content, and initial concentrations of the pathogen for those
studies.
Christensen, K.K., M. Carlsaek, and E. Kron. 2002. Strategies for evaluating the sanitary quality of composting. J.
Appl. Microbiol. 92:1143-1158.
The direct process evaluation is considered unreliable for evaluating the overall sanitary process. Instead, it is a valuable tool
for identifying parameters for process optimization in different zones and for measuring elimination patterns of pathogens not
normally present in the waste.
Chun-ming, G., K. Inoue, S. Inanaga, and T. Someya. 2005. Survival of pathogenic bacteria in compost with special
reference to Escherichia coli. J. Environ. Sci. China 17:770-774.
The results indicated that moisture content was a very important factor to the heat sensitivity of pathogenic bacteria in
compost with E. coli being more sensitive in compost of high moisture content (70%) than that in compost of low moisture
content (40%).
Çížek, A., I. Literák, and P. Scheeer. 2000. Survival of Escherichia coli O157 in faeces of experimentally infected rats
and domestic pigeons. Lett. Appl. Microbiol. 31:349-352.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
composting systems
(last updated on 4/5/2012)
Cooper, R.C. and C.G. Golueke. 1979. Survival of enteric bacteria and viruses in compost and its leachate. Compost
Sci. Util. 20:29-34.
Frequency of turning made no apparent different in rate of die-off of indicator bacteria.
A key point stressed was that at no one point in time was every last particle in the pile exposed to lethal temperature. In
particular, a gradation of zones existed from the interior (high temperature) zone to the outermost (ambient temperature)
zone. Within this gradation, a zone (approximately 25% of the composting mass) occurred within the gradation in which
temperatures were optimum (lower than 50°C) for the organisms in question. In this study, a sizeable portion of the material
had a moisture content less than 50% and this low moisture may have mitigated the effect of high temperature.
Cornet, I., E. Van Derlinden, A.M. Cappuyns, and J.F. Van Impe. 2010. Heat stress adaptation of Escherichia coli
under dynamic conditions: effect of inoculum size. Lett. Appl. Microbiol. 51:450-455.
Initial cell concentration had no effect on the organism’s temperature resistance, rather the increase in temperature resistance
of the sensitive population was because of the change of the physiological state to the stationary phase.
Costantini, V.P. A.C. Azevedo, X. Li, M.C. Williams, F.C. Michel, Jr., and L.J. Saif. 2007. Effects of different animal
waste treatment technologies on detection and viability of porcine enteric viruses. Appl. Environ. Microbiol. 73:52845291.
Cøte, C., A. Vlilleneuve, L. Lessard, and S. Quessy. 2006. Fate of pathogenic and nonpathogenic microorganisms
during storage of liquid hog manure in Quebec. Livestock Sci. 102:204-210.
The maximal persistence of Salmonella observed in this study was 88 days whereas a 73-day storage time was insufficient
for the elimination of Y. enterocolitica.
Déportes, I., J.-L. Benoit-Guyod, D. Zmirou, and M.-C. Bouvier. 1998. Microbial disinfection capacity of municipal
solid (MSW) composting. J. Appl. Microbiol. 85:238-246.
Droffner, M.L. and Brinton, W.F. 1995. Survival of Escherichia coli and Salmonella populations in aerobic
thermophilic composts as measured with DNA gene probes. Zentralblatt fur Hygiene und Umweltmedizin 197:387397.
Gene probes were used to determine at what time during the composting and at what temperature E. coli and Salmonella
became undetectable. Using this measurement, both organisms were shown to survive for extensive periods at what are
normally considered lethal temperatures for these bacteria.
Droffner, M.L. and W.F. Brinton. 1996. Occurrence and detection of viable Listeria in food scrap compost. Zbl. Hyg.
199:51-59.
Using food scraps and leaves as the composting materials, survival of Listeria (initial concentrations of 7 log CFU/g)
occurred when exposed to temperatures as high as 64°C for a short period of time.
Droffner, M.L., W.F. Brinton, Jr., and E. Evans. 1995. Evidence for the prominence of well characterized mesophilic
bacteria in thermophilic (50-70°C) composting environments. Biomass and Bioenergy 8:191-195.
S. typhimurium, E. coli, and P. aeruginosa all create mutants capable of growth at 54C. Based on 16sRNA gene probe assay
kits, both E. coli and Salmonella were shown to survive for days in compost with temperatures of at least 60°C.
Duggan, J., M.P. Bates, and C.A. Phillips. 2001. The efficacy of subsurface flow reed bed treatment in the removal of
Campylobacter spp., faecal coliforms and Escherichia coli from poultry litter. Int. J. Environ. Hlth. Res. 11:168-180.
Duriez, P., Y. Zhan;g, Z. Lu, A. Scott, and E. Topp. 2008. Loss of virulence genes in Escherichia coli populations
during manure storage on a commercial swine farm. Appl. Environ. Microbiol. 74:3935-3942.
In a swine manure holding tank, E. coli population was initially dominated by a single genotype, all isolates of which carried
several virulence genes. After 7 weeks, a genotype that did not carry any virulence genes dominated the surviving
population.
Elving, J., J.R. Ottoson, B. Vinnerås, and A. Albihn. 2010. Growth potential of faecal bacteria in simulated
psychrophilic/mesophilic zones during composting of organic waste. J. Appl. Microbiol. 108:1974-1981.
Salmonella Typhimurium, E. coli, and Enterococcus spp. had the potential for regrowth in material from active composting
systems but inactivation generally occurred over time in mature compost material.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
composting systems
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Erickson, M.C., M. Islam, C. Sheppard, J. Liao, and M.P. Doyle. 2004. Reduction of Escherichia coli O157:H7 and
Salmonella enterica serovar Enteritidis in chicken manure by larvae of the black soldier fly. J. Food Prot. 67:685-690.
Soldier fly larvae accelerated inactivation of E. coli O157: H7 in chicken manure but had no effect in cow manure and
enhanced survival in hog manure. Transfer of contaminated larvae to fresh chicken manure led to cross-contamination of the
fresh manure.
Franz, E., A.D. van Diepeningen, O.J. de Vos, and A.H.C. van Bruggen. 2005. Effects of cattle feeding regimen and
soil management type on the fate of Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium in
manure, manure-amended soil, and lettuce. Appl. Environ. Microbiol. 71:6165-6174.
Survival times of Salmonella Typhimurium and E. coli O157:H7 depended not only on temperature but also on the manure
composition, which is determined by the feeding regimen.
Franz, E., M.M. Klerks, O.J. de Vos, A.J. Termorshuizen, and A.H.C. van Bruggen. 2007. Prevalence of Shiga toxinproducing Escherichia coli stx1, stx2, eaeA, and rfbE genes and survival of E. coli O157:H7 in manure from organic
and low-input conventional dairy farms. Appl. Environ. Microbiol. 73:2180-2190.
The survival curves of E. coli O157:H7 in manure was nonlinear and showed considerable variation. All survival curves
could be fit to the biphasic Geeraerd model with good accuracy (significant and high R 2). It was proposed that the observed
nonlinear biphasic pattern of the survival curve is the result of changing nutrient status of the manure over time (and thereby
changing competition pressure), instead of the presence of subpopulations differing in the level of resistance.
Fremaux, B., M.L. Delignette-Muller, C. Prigent-Combaret, A. Gleizal, and C. Vernozy-Rozand. 2007. Growth and
survival of non-O157:H7 shiga-toxin-producing Escherichia coli in cow manure. J. Appl. Microbiol. 102:89-99.
Eight STEC strains, none of them belonged to the O157:H7 serotype.
Five heaps were constructed with a rectangular base of approx. 2 m2 and a height of 1 m, kept indoors at 15°C, and three of
the heaps were unturned while other two were turned by mixing them three times during the study at interval of 7 days
between each turning. The log-linear model with tailing was fitted to STEC counts data in unturned heaps. In turned piles,
noticeable fluctuation of both STEC counts and temperature in each sampled site, therefore no model could fit the data.
STEC strains could not be detected after 42 days.
Fukushima, H., K. Hoshina, and M. Gomyoda. 1999. Long-term survival of Shiga toxin-producing Escherichia coli
O26, O111, and O157 in bovine feces. Appl. Environ. Microbiol. 65:5177-5181.
STEC O26, O111, and O157 were inoculated into bovine feces at 1, 3, and 5 log CFU/g, placed in closed plastic bags, and
held at 5, 15, and 25°C. All 3 pathogens survived at 5 and 25°C for 1 to 4 weeks and at 15° for 1 to 8 weeks when inoculated
at the low concentration. On samples inoculated with the middle and high concentrations, O26, O111 and O157 survived at
25°C for 3 to 12 weeks, at 15°C for 1 to 18 weeks, and at 5°C for 2 to 14 weeks, respectively.
Garfield, L.M. and M.J. Walker. 2008. Water potential changes in fecal matter and Escherichia coli survival. J. Appl.
Microbiol. 105:1009-1016.
Water activity of 0.85 is approximately equivalent to a water potential of -22.4 MPa at 25°C. E. coli did not survive when
water potential in canine feces reached approx. -22 MPa (0.2 g/g). Nearly complete die-off was found at 15 and 60 h for high
and low evaporation rates, respectively.
Gavaghan, P.D., J.L. Sykora, W. Jakubowski, C.A. Sorber, A.M. Sninsky, M.D. Lichte, and G. Keleti. 1993.
Inactivation of Giardia by anaerobic digestion of sludge. Wat. Sci. Tech. 27(3-4):111-114.
99.9% of the cysts were inactivated within approximately 18 h of exposure to anaerobic digestion at 37°C.
Germer, J., M.Y. Boh, M. Schoeffler, and P. Amoah. 2010. Temperature and deactivation of microbial faecal
indicators during small scale co-composting of faecal matter. Waste Management 30:185-191.
The reduction of E. coli, Enterococcus faecalis, and Salmonella senftenberg in test containment systems (5-6 log CFU/g)
placed in the core of the compost piles exceeded 5 logs in all cases but recolonization from the cooler outer layers appeared
to interfere with the sanitization efficiency of the substrate itself. Extending the composting process to over 4 months
ensured that the load of E. coli was reduced to less than 3 log CFU/g and Salmonella were undetectable.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
composting systems
(last updated on 4/5/2012)
Goncalves, V.P. and J.M. Morin. 2007. Fate of non O157 Shiga toxigenic Escherichia coli in composted cattle manure.
Arquivo Brasileiro de Medicina Veterinaria E Zootecnia 59:825-831.
The STEC strains appeared to be more sensitive to high temperatures than ordinary E. coli in either a 0.6 m deep cave opened
in the soil or a one meter high solid manure heap in a pyramidal architecture. STEC non-O157 E. coli cells survived for 8,
25, and 30 days at 42, 40, and 38°C, respectively in the deep cave whereas in the heap, survival for 4, 4, and 7 days occurred
at 65, 58, and 52°C, respectively.
Graczyk, T.K., M. Kacprzak, E. Neczaj, H. Graczyk, F.E. Lucy, and A.S. Girouard. 2007. Human-virulent
microsporidian spores in solid waste landfill leachate and sewage sludge, and effects of sanitization treatments on
their inactivation. Parasitol. Res. 101:569-575.
Sonication reduced the load of human virulent microsporidian spores (initial concentrations 16 - 18 spores/g) to
nondetectable levels in 19 out of 27 samples (70.4%). Quicklime stabilization was 100% effective whereas microwave
energy disintegration was 100% ineffective against the spores of E. bieneusi and E. intestinalis.
Gradel, K.O., J.C. Jørgensen, J.S. Andersen, and J.E.L. Corry. 2003. Laboratory heating studies with Salmonella spp.
and Escherichia coli in organic matter, with a view to decontamination of poultry houses. J. Appl. Microbiol. 94:919928.
At low humidity, survivors were found in dried feces at every sampling time and every final heating temperature (60°C
during a 24-h period).
Grewal, S., S. Sreevatsan, and F.C. Michel, Jr. 2007. Persistence of Listeria and Salmonella during swine manure
treatment. Compost Sci. Util. 15:53-62.
After 56 days, L. monocytogenes (initial population of 6 log CFU/g) was still detected in one of three experimental replicates
in the 55°C vessels although at very low levels (10/g). In compost incubated at 25°C, the Listeria MPN had declined to 57/g
and only one out of 3 replicates showed the presence of L. monocytogenes. The liquid treatment with aeration showed no L.
monocytogenes on days 7 and 14. By days 14 and 28, L. monocytogenes was present in only 2 and 1 replicate of the
nonaerated liquid treatment, respectively, and no L. moncytogenes was detected thereafter.
No viable cells of Salmonella were detected (<11/g) after 28 days in the compost treatment held at 55°C (initial population of
6 log CFU/g). In the compost incubated at 25°C, all 3 replications of this treatment showed the presence of Salmonella
through day 56. Salmonella was undetectable on day 56 of the aerated liquid treatment whereas in the unaerated slurry
treatment, Salmonella was still present in 2 of the 3 replicates on day 45.
Grewal, S.K., S. Rajeev, S. Sreevatsan, and F.D. Michel, Jr. 2006. Persistence of Mycobacterium avium subsp.
paratuberculosis and other zoonotic pathogens during simulated composting, manure packing, and liquid storage of
dairy manure. Appl. Environ. Microbiol. 72:564-574.
Manure was inoculated with M. paratuberculosis to give 6 log CFU/g in the final mixes.
Thermophilic compost mixtures were prepared with manure and sawdust or straw and 60% moisture. Treatment was
incubated at 55°C in a laboratory scale compost system. Another batch was incubated at 25°C. The temperatures of both
compost mixes increased from the set points of 55°C and 25°C due to microbial activity. The temperatures remained 3 to
4°C above the set points in all the compost treatments for approximately 10 days, indicating high microbial activity during
this period. Maximum temperature increase was greater in the straw than in the sawdust.
E. coli, Salmonella and Listeria were all detected initially in the manure using enrichment protocols. After 3 days of
composting at 55°C, none of these organisms were detectable. Composting at 25°C required 2 to 8 weeks before
concentrations of these organisms became undetectable. In liquid storage (incubation temperature < 25°C), none of the
organisms were detectable after 56 days.
M. paratuberculosis was culturable through day 56 but not on day 3, 7, or 175. Competition may have limited its detection
by way of culturing. Another possible explanation for heterogeneity in samples from the same treatment could be the
tendency of M. paratuberculosis organisms to form large clumps. No M. paratuberculosis organisms were culturable after
just 3 days in the composting treatments at both 55 and 25°C incubation temperatures whereas E. coli, Salmonella and
Listeria could be detected initially in the manure using enrichment protocols but still required 2 to 8 weeks before
concentrations of these organisms were reduced to undetectable.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Guan, J., M. Chan, C. Grenier, D.C. Wilkie, B.W. Brooks, and J.L. Spencer. 2009. Survival of avian influenza and
Newcastle disease viruses in compost and at ambient temperatures based on virus isolation and real-time reverse
transcriptase PCR. Avian Dis. 53:26-33.
Temperatures in compost ranged from 50 to 60°C, and viruses (5 log PFU) had been killed in all specimens in mesh bags by
day 7. In comparison, viruses in sealed vials remained viable to day 10 but were no longer detected on day 21.
Guzmán, C., J. Jofre, M. Montemayor, and F. Lucena. 2007. Occurrence and levels of indicators and selected
pathogens in different sludges and biosolids. J. Appl. Microbiol. 103:2420-2429.
After composting (digested-dewatered sludge composted in windrows for 4 weeks), 5 of the 6 compost samples still had
viable Cryptosporidium oocysts and averaged 23 oocysts/gdw.
Hanajima, D., K. Kuroda, Y. Fukumoto, and K. Haga. 2004. Growth of seeded Escherichia coli in rewetted cattle
waste compost of different stages. Asian-Australasian J. Anim. Sci. 17:278-282.
Samples collected during or immediately after the thermophilic phase (day 7) showed the highest growth of E. coli. Growth
in samples more than 13 d old were not significantly different from those of aged compost samples.
Hanajima, D., K. Kuroda, Y. Fukumoto, and K. Haga. 2006. Effect of addition of organic waste on reduction of
Escherichia coli during cattle feces composting under high-moisture condition. Bioresource Technol. 97:1626-1630.
Heat exposure in the initial phase of composting appears to be a key factor for E. coli elimination from compost.
Hassen, A, K. Belguith, N. Jedidi, A. Cherif, M. Cherif, and A. Boudabous. 2001. Microbial characterization during
composting of municipal solid waste. Bioresource Technol. 80:217-225.
In windrows (1.5 x 2 x 3 m), Salmonella disappeared by the 25th day of composting as soon as the temperature reached 55°C.
Heinonen-Tanski, H., E.M. Niskanen, P. Salmela, and E. Lanki. 1998. Salmonella in animal slurry can be destroyed by
aeration at low temperatures. J. Appl. Microbiol. 85:277-281.
Reductions ranging from greater than 99% of the initial number to no detectable Salmonella, could be reached after 2-5
weeks using aeration in farm-scale slurry tanks when either cattle slurry was contaminated by Salmonella infantis or pig
slurry was contaminated by Salmonella typhimurium (initial concentration 4 log CFU/g).
Herold, T., R. Kliche, and A. Hensel. 1999. Influence of aerobic fermentation on survival of Salmonella typhimurium
(DT 104) and Escherichia coli in untreated liquid pig manure. Berl. Münch. Tierärztl. Wschr. 112:448-453.
Hess, T.F., I. Grdzelishvili, H. Sheng, and C.J. Hovde. 2004. Heat inactivation of E. coli during manure composting.
Compost Sci. Util. 12:314-322.
Composting experiments were conducted in laboratory-scale bioreactors and used bovine feces mixed with straw (target C:N
ratio of 20-30:1 and a moisture content of ~70%). Laboratory-grown E. coli O157:H7 inoculated into the initial compost
material (~6 log CFU/g) were not detected after approximately 300 degree days of heating whereas E. coli O157:H7 from
infected cattle waste and included in compost materials were not detected after approximately 180 degree days of heating.
Hill, V.R., and M.D. Sobsey. 2003. Performance of swine waste lagoons for removing Salmonella and enteric microbial
indicators. Trans. ASAE 46:781-788. Single-stage, primary lagoons, can substantially reduce concentrations of
Salmonella in flushed swine waste but are not effective for reducing concentrations of C. perfringens spores. Salmonella can
be further reduced in two-stage lagoon systems, yielding overall reductions that are more protective of public health.
Himathongkham, S. and H. Riemann. 1999. Destruction of Salmonella typhimurium, Escherichia coli O157:H7 and
Listeria monocytogenes in chicken manure by drying and/or gassing with ammonia. FEMS Microbiol. Lett. 171:179182.
Drying alone and gassing with ammonia alone resulted in less than 2 log reductions. Drying followed by gassing with
ammonia (24-h treatment) resulted in a 4-log reduction of E. coli O157:H7, 3 logs for S. typhimurium and 2.5 logs for L.
mononcytogenes. When the treatment with ammonia gas was extended to 72 h, resulted in an almost 8-log reduction of S.
typhimurium.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Himathongkham, S. Nuanualsuwan, and H. Riemann. 1999. Survival of Salmonella entertidis and Salmonella
typhimurium in chicken manure at different levels of water activity. FEMS Microbiol. Lett. 172:159-163.
A water activity level of 0.89 corresponds to a total moisture level of 57%..
The water activity was adjusted by means of saturated salts with defined equilibrium relative humidity and the manure
samples were stored aerobically at 20°C. At water activity levels higher than 0.93, increase in CFUs occurred. At water
activities between 0.75 and 0.89, a 3-log reduction occurred after 8 h and a 6-log reduction after 8 days. At higher and lower
water activities, the population reduction was less extensive.
Himathongkham, S., H. Riemann, S. Bahari, S. Nuanualsuwan, P. Kass, and D.O. Cliver. 2000. Survival of Salmonella
typhimurium and Escherichia coli O157:H7 in poultry manure and manure slurry at sublethal temperatures. Avian
Dis. 44:853-860.
Escherichia coli O157:H7 consistently exhibited slightly slower inactivation than S. typhimurium and inactivation was slower
in slurries compared to solid manure. Accumulation of free ammonia in poultry manure appeared to be an important factor in
inactivation of the pathogen.
Himathongkham, S., S. Bahari, H. Riemann, and D. Cliver. 1999. Survival of Escherichia coli O157:H7 and
Salmonella typhimurium in cow manure and cow manure slurry. FEMS Microbiol. Lett. 178:251-257.
In a few cases, had an initial increase in levels but in general, the rate of inactivation corresponded to a first order reaction
with fairly well-defined decimal reductions times (DRT). It was suggested that DRT values could then be used in risk
assessments to predict how long manure should be held before application to a field used to grow produce.
In cow manure, survival of E. coli O157:H7 was greater than S. typhimurium in the top layer of manure where moisture
levels decreased from 88% to 12%. In bottom and middle portions of manure where moisture levels remained the same, no
difference in inactivation rates between the two pathogens.
Ammonia levels changed only slightly during storage and therefore did not have an effet on pathogen inactivation.
Himathongkham, S., S. Nuanualsuwan, and H. Riemann. 1999. Survival of Salmonella enteritidis and Salmonella
typhimurium in chicken manure at different levels of water activity. FEMS Microbiol. Lett. 172:159-163.
At aw levels higher than 0.93, Salmonella increased initially however, it decreased at aw levels of 0.89-0.75. Over extended
storage, Salmonella decreased at an aw of 0.89 (corresponded to moisture level of 57%) and is probably the result of ammonia
formation by the indigenous microflora accompanied by an increase in pH.
Hussong, D., W.D. Burge, and N.K. Enkiri. 1985. Occurrence, growth, and suppression of Salmonellae in compost
sewage sludge. Appl. Environ. Microbiol. 50:887-893.
It was concluded that the active indigenous flora of compost establishes a homeostatic barrier to colonization by salmonellae,
and in the absence of competing flora, reinoculated salmonellae may grow to potentially hazardous densities.
Hutchison, M.L., L.D. Walters, A. Moore, and S.M. Avery. 2005. Decline of zoonotic agents in liquid livestock wastes
stored in batches on-farm. J. Appl. Microbiol. 99:58-65.
Declines in E. coli O157:H7 were significantly slower than Salmonella spp. while Campylobacter jejuni declined
significantly more rapidly than the other pathogens. On average, bacterial declines were not affected by the season of waste
deposition and storage or by the dry matter content of the wastes, but were more rapid in dairy or beef cattle slurries than pig
slurries. Tailing was exhibited by some of the pathogen-waste combinations and is an important consideration when
determining the length of waste storage times which are required for pathogen depletion along with the initial pathogen
concentration.
Hutchison, M.L., L.D. Walters, A. Moore, K.M. Crookes, and S.M. Avery. 2004. Effect of length of time before
incorporation on survival of pathogenic bacteria present in livestock wastes applied to agricultural soil. Appl.
Environ. Microbiol. 70:5111-5118.
Bacterial decline was significantly more rapid for all waste types when they were left on the soil surface and indicate that not
incorporating contaminated livestock wastes into soil is a potential intervention measure that may help to limit the spread of
zoonotic agents further up the food chain. Disadvantages to this practice are the increased likelihood of insect infestation and
the spread of zoonotic agents to the wider environment particularly with surface runoff.
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Hutchison, M.L., L.D. Walters, S.M. Avery, and A. Moore. 2005. Decline of zoonotic agents in livestock waste and
bedding heaps. J. Appl. Microbiol. 99:354-362.
Temperatures of >50°C were typically achieved at the core of the heaps (5 m3) of cattle, sheep, or pig wastes mixed with
bedding materials. Observed tailing in pathogen decline such that pathogens could still be recovered for up to 3 months from
the heaps (5-10 CFU/g). As the initial decline was first order, it was possible to calculate decimal reduction times (D-values)
for each pathogen and waste type. Based on decimal reduction times, Listeria declines were significantly slower than those
observed for E. coli and Salmonella but no differences when different waste types were compared.
Took 93 days before Salmonella, E. coli O157:H7 and Listeria fell below detection limits (25 CFU/g) in beef cattle compost
samples whereas in dairy cattle compost samples, took 8, 32, and 8 days to fall below detection limits. For pig and poultry
compost samples, # of days were 32, 8 and 8, and 62, 32, and 62, respectively.
Inglis, G.D., T.A. McAllister, F.J. Larney, and E. Topp. 2010. Prolonged survival of Campylobacter species in bovine
manure compost. Appl. Environ. Microbiol. 76:1110-1119.
Using molecular technique, DNA of campylobacters shed in bovine feces persisted in manure in pens for ca. 2.5 months and
throughout the active and curing phases of composting (ca. 7.7 months). Utilized an EMA method to amplify DNA only
from cells possessing an intact cell membrane.
Inoue, M., S. Uga., T. Oda, S.K. Rai, G. Vesey, and H. Hotta. 2006. Changes of physical and biochemical properties of
Cryptosporidium oocysts with various storage conditions. Water Res. 40:881-886.
When stored at 18°C as a fecal pellet, the specific gravity of the oocysts increased and a significant decrease in the oocysts
resistance to ultrasonics occurred. These changes in oocysts properties may affect the performance of methods used to detect
oocysts in water samples.
Ivanov, V.N., J.-Y. Wang, O.V. Stabnikova, S.T.-L. Tay, and J.-H. Tay. 2004. Microbiological monitoring in the
biodegradation of sewage sludge and food waste. J. Appl. Microbiol. 96:641-647.
Viable enterobacterial cells were determined by fluorescent in situ hybridization (FISH) with Enterobacteriaceae-specific
oligonucleotide probe and flow cytometry. Based on this method, enterobacteria could survive under treatment of sewage
sludge and food waste at 60°C for 13 days.
Jarvis, G.N., M.W. Fields, D.A. Adamovich, C.E. Arthurs, and J.B. Russell. 2001. The mechanism of carbonate killing
of Escherichia coli. Lett. Appl. Microbiol. 33:196-200.
The antibacterial activity of carbonate seems to be mediated by divalent metal binding.
Jiang, X., J. Morgan, and M.P. Doyle. 2003. Fate of Escherichia coli O157:H7 during composting of bovine manure in
a laboratory-scale bioreactor. J. Food Prot. 66:25-30.
When inoculated at an initial level of 7 log CFU/g and held in bioreactor with ambient temperature of 50°C, E. coli O157:H7
survived for 7 days but not for 14 days at all three sampling locations (top, middle and bottom), as indicated by either direct
plating or enrichment culture. E. coli O157:H7 was inactivated at different rates, with more extensive survival at the
location in the bioreactor at which the compost temperature was lowest and the moisture content was highest.
Jiang, X., J. Morgan, and M.P. Doyle. 2003. Thermal inactivation of Escherichia coli O157:H7 in cow manure
compost. J. Food Prot. 66:1771-1777.
Using finished cow manure compost to determine inactivation curves, the D-values for E. coli O157:H7 at 50°C were 145
and 151 min for autoclaved and unautoclaved compost, respectively. Considerable tailing was observed for inactivation
curves, especially at 60, 65, and 70°C.
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Jones, K. 2001. Campylobacters in water, sewage and the environment. J. Appl. Microbiol. 90:68S-79S.
Although intestinal carriage of campylobacters is ubiquitous in livestock, domestic animals, wild animals, wild birds and
poultry, contamination of the environment with the bacteria in feces is intermittent and varies seasonally, depending on
factors such as stress and changes in diet. The presence of campylobacters in environmental samples can be taken as a sign
of recent fecal contamination, because not only are campylobacters unable to multiply outside warm-blooded host animals,
they also survive for a shorter time than the usual indicators, fecal coliforms and fecal streptococci.
The number of thermophilic campylobacters in the final effluents from waste water treated water depends on the type of
treatment. Primary settlement reduces the numbers slightly and they still show the same seasonal pattern as the inputs.
Secondary treatment reduces the numbers considerably and tertiary treatment completely eliminates them. Natural
populations of Campylobacter in sewage effluent became unculturable after only 15 min of direct sunlight.
As Campylobacter cannot grow in the environment and survival is limited, it has been suggested that changes in the size of
the Campylobacter population within livestock and poultry and the vehicles and vectors which transmit Campylobacter from
one host to another, play a significant role in the epidemiology of this organism. There are cyclical variations in the size of
the Campylobacter populations within the intestines of cattle, sheep, and chickens, which may be responsible for different
levels of carcass contamination at different times of the year and contribute to the seasonality of infections shown in man.
Kannangara, T., T. Forge, and B. Dang. 2006. Effects of aeration, molasses, kelp, compost type, and carrot juice on
the growth of Escherichia coli in compost teas. Compost Sci. Util. 14:40-47.
The E. coli density was positively correlated with nutrient concentrations. Even though E. coli is a facultative anaerobe, its
growth was significantly higher in nonaerated teas than in aerated teas but presence of carrot juice inhibited growth.
Kassem, I.I., Y. Sanad, D. Gangaiah, M. Lilburn, J. LeJeune, and G. Rajashekara. 2010. Use of bioluminescence
imaging to monitor Campylobacter survival in chicken litter. J. Appl. Microbiol. 109:1988-1997.
At initial concentrations of 1-2 x 106 CFU/g, C. jejuni and C. coli survived and grew for at least 20 days in reused (old) litter
while the growth of these pathogens was inhibited in clean (new) litter. In turn, the percentage of Campylobacter-positive
chickens in the reused litter enclosures were significantly higher than those in the new litter enclosures.
Kim, J., J. Diao, M.W. Shepherd, Jr., R. Singh, S.D. Heringa, C. Gong, and X. Jiang. 2012. Validating thermal
inactivation of Salmonella spp. in fresh and aged chicken litter. Appl. Environ. Microbiol. 78:1302-1307.
A 7-log reduction of Salmonella was achieved by exposing fresh chicken litter for 80.5 to 100.8, 78.4 to 93.1, and 44.1 to 63
min at 70, 75, and 80°C, respectively, depending on initial moisture contents. However, the aged chicken litter required more
heat treatment.
Kim, H., F. Luo, and X. Jiang. 2009. Factors impacting the regrowth of Escherichia coli O157:H7 in dairy manure
compost. J. Food Prot. 72:1576-1584.
Repopulation (increase from ca. 1 to 4.8 log CFU/g) occurred in autoclaved compost with a moisture content as low as 20%
(water activity of 0.986) in the presence of background microflora of 2.3 to 3.9 log CFU/g. E. coli O157 regrowth was
suppressed by background microflora at ca. 6.5 log CFU/g. Increasing the inoculum level to ca. 3 log CFU/g, E. coli
O157:H7 could regrow in the presence of high levels of background microflora.
Kim, J. and X. Jiang. 2009. The growth potential of Escherichia coli O157:H7, Salmonella spp. and Listeria
monocytogenes in dairy manure-based compost in a greenhouse setting under different seasons. J. Appl. Microbiol.
109:2095-2104.
The 3 pathogens were inoculated separately into dry compost to yield ca. 1 log CFU/g. Moisture levels in compost were
adjusted to 10-50%. In nonautoclaved compost, there was no growth of any pathogen regardless of initial moisture level or
season. An initial moisture content of 40% was required for growth in autoclaved compost during the spring and summer
trials, whereas an initial moisture content of 30% supported the growth of pathogens for 2 days during the winter trial. The
persistence of Salmonella in compost with lower initial moisture was much less than E. coli O157:H7 during the spring or
summer months. Listeria monocytogenes survived longest among the three pathogens in compost with less than initial
moisture content of 20%.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Kim, J., M.W. Shepherd, Jr., and X. Jiang. 2009. Evaluating the effect of environmental factors on pathogen regrowth
in compost extract. Microb. Ecol 58:498-508.
Water extract of commercially available dairy compost was used as a model system. Compost extract samples of all ages
supported the regrowth of both Salmonella and E. coli O157:H7 with population increases ranging from 0.95 to 2.32 log
CFU/ml. At 22°C, Salmonella spp. regrew in both 1:2 and 1:5 compost extracts but not in 1:10 whereas E. coli O157:H7 and
L. monocytogenes multiplied in all compost extracts. For all 3 pathogens, incubation at 22°C provides better conditions for
regrowth than at 35°C. Adaptation of both Salmonella and E. coli O157:H7 to nutrient-limited broth (1/10 strength of TSB)
facilitated regrowth in compost extracts compared to cultures grown previously in full strength of TSB. Pathogen regrowth
occurred in the most diluted sterile compost extract when indigenous microorganisms were absent, but required a more
concentrated compost extract (1:2) when background microorganisms were present at 5 log CFU/ml.
Kim, J., C.M. Miller, M.W. Shepherd, Jr., X. Liu, and X. Jiang. 2011. Impact of indigenous microorganisms on
Escherichia coli O157:H7 growth in cured compost. Bioresource Technol. 102:9619-9625.
Concluded that dry heat treated compost (DHTC) is a better model system for studying the impact of indigenous
microorganisms on pathogen growth than acclimated autoclaved compost (AAC) since similar types of microorganisms are
found both in DHTC and control compost samples. Overall, the growth of E. coli O157:H7 was less in DHTC than AAC
when the same populations of indigenous mesophiles were present, regardless of temperature or moisture content. Greater
proliferation of E. coli O157:H7 in AAC compared to DHTC may be partially explained by the reduction of both
actinomycetes and thermophiles in AAC. Higher moistures (20 and 40%) supported higher increases in pathogen growth
than low moisture (20%), regardless of compost treatment or incubation temperature.
Knop, M., H. Pohle, and A. Bergmann. 1996. Investigations on hygienisation of biowaste compost by using Salmonella
enteritidis as a pathogen indicator and survival of Salmonellae in seepage water. Berliner und Munchener
Tierarztliche Wochenschrift 109:451-456.
Every time when Salmonella was detected in input material, the same serotypes were to be found in seepage water and
survived there.
Kudva, I.T., Blanch, K. and Houde, C.J. 1998. Analysis of Escherichia coli O157:H7 survival in ovine or bovine
manure and manure slurry. Applied and Environmental Microbiology 64: 3166-3174.
In this study, observed that E. coli O157:H7 survived in a manure pile from sheep for 21 months (concentrations ranged from
<2 log to 6 log CFU/g). Aeration of piles decreased survival both in ovine and bovine manure. In the laboratory, E. coli
O157:H7 survived best in effluents with a high solid content incubated without aeration at temperatures below 23°C. Shiga
toxin type 1 and 2 genes in E. coli O157:H7 had little or no influence on bacterial survival in manure or manure slurry.
Lafond, S., T. Paré, H. Dinel, M. Schnitzer, J.R. Chambers, and A. Jaouich. 2002. Composting duck excreta enriched
wood shavings: C and N transformations and bacterial pathogen reductions. J. Environ. Sci. Health B37:173-186.
Lagunas-Solar, M.C., J.S. Cullor, N.X. Zeng, T.D. Truong, T.K. Essert, W.L. Smith, and C. Piña. 2005. Disinfection
of dairy and animal farm wastewater with radiofrequency power. J. Dairy Sci. 88:4130-4131.
Wastewater was inoculated with 6 to 9 log of Salmonella spp., E. coli O157:H7, or Mycobacterium avium sp.
paratuberculosis. Applied radiofrequency (RF) for < 1 min during which time the water heated to temperatures of 60 to
65°C. Bacterial pathogens were rapidly inactivated.
Lang, N.L. and S.R. Smith. 2008. Time and temperature inactivation kinetics of enteric bacteria relevant to sewage
sludge treatment processes for agricultural use. Wat. Res. 42:2229-2241.
The chemical environment of the heating matrix significantly influenced exponential decay rates when enteric bacterial
populations were thermally stressed. Decay rates were up to 3 times faster in the simulated biosolids matrix relative to the
laboratory broth. There was no evidence of direct thermal inactivation taking place at mesophilic temperatures.
Lemunier, M., C. Francou, S. Rousseaux, S. Houot, P. Dantigny, P. Piveteau, and J. Guzzo. 2005. Long-term survival
of pathogenic and sanitation indicator bacteria in experimental biowaste composts. Appl. Environ. Microbiol.
71:5779-5786.
Nonsterile composts did not support pathogen growth at 25°C, but survival of Salmonella serovar Enteritidis was observed in
all composts, with longer survival (3 months) occurring in mature composts (8 and 12 weeks of composting). E. coli and L.
monocytogenes survival was observed only in 4-week old composts and never in older composts.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Lowe, R.M.S., K. Munns, L.B. Selinger, L. Kremenik, D. Baines, T.A. McAllister, and R. Sharma. 2010. Factors
influencing the persistence of Escherichia coli O157:H7 lineages in feces from cattle fed grain versus grass hay diets.
Can. J. Microbiol. 56:667-675.
Three strains of each lineage I and II were inoculated into grain-fed or hay-fed feces, and their persistence was monitored
over 28 days. No significant differences in E. coli O157:H7 survival between the 2 lineages in both fecal types was found at
the examined temperatures. Regardless of lineage type, E. coli O157:H7 CFUs were significantly higher in grain-fed than in
hay-fed feces at 4 and 25°C and may be in response to the higher concentrations of volatile fatty acids produced in grain-fed
than in hay-fed feces.
Lund, B., V.F. Jensen, P. Have, and B. Ahring. 1996. Inactivation of virus during anaerobic digestion of manure in
laboratory scale biogas reactors. J. Gen. Molec. Microbiol. 69:25-31.
For porcine parvovirus, a minimum guaranteed retention time (MGRT) of 11-12 hours is necessary at 55°C in the initial
phase (0-4 hours) and 54 hours hereafter (4-48 h). Correspondingly, for bovine enterovirus a MGRT of 23 hours was
necessary at 35°C and <0.5 hours at 55°C. The data indicated that fecal streptococci measurements give a good indication of
inactivation of enterovirus and other more heat sensitive virus.
Lung, A.J., C.-M. Lin, J.M. Kim, M.R. Marshall, R. Nordstedt, N.P. Thompson, and C.I. Wei. 2001. Destruction of
Escherichia coli O157:H7 and Salmonella enteritidis in cow manure composting. J. Food Prot. 64:1309-1314.
E. coli O157:H7 was not detected after 72 h of composting at 45°C (temperature of incubators in which systems were
placed), and Salmonella Enteritidis was not detected after 48 h.
Macklin, K.S. and J.T. Krehling. 2010. The use of metam-sodium to reduce bacteria in poultry litter. J. Appl. Poult.
Res. 19:274-278.
Common soil fumigant, metam-sodium, was added to poultry litter up to 5 gal/ton (20.86 mL/kg) but had only a minor effect
in reducing C. perfringens numbers.
Macklin, K.S., J.B. Hess, and S.F. Bilgili. 2008. In-house windrow composting and its effects on foodborne pathogens.
J. Appl. Poult. Res. 17:121-127.
Piles (1 x 1 x 1 m) of used chicken liter (w/ pine shavings as bedding were inoculated with 11.6, 10.2, and 9.8 log of
Campylobacter spp., Salmonella spp., and C. perfringens, respectively. After 7 days, no Salmonella or Campylobacter was
detected in composted samples (placed at 25 and 50 cm into litter pile). No Campylobacter was detected in uncomposted
samples (placed at surface); however, Salmonella was present in uncomposted samples at 1.9 log CFU/g. C. perfringens was
present in 7-d uncomposted and composted samples at 1.4 and 0.8 log CFU/g. The average temperature of the exterior of the
pile was 5 to 10°C higher than the ambient temperature and while not high enough to kill any microorganisms, this warming
did increase the amount of ammonia generated that was suggested as responsible for reducing the bacterial levels from the
surface of the compost pile.
Mannion, C., P.B. Lynch, J. Egan, and F.C. Leonard. 2007. Seasonal effects on the survival characteristics of
Salmonella Typhimurium and Salmonella Derby in pig slurry during storage. J. Appl. Microbiol. 103:1386-1392.
At the higher inoculum level (5 log), S. Typhimurium and S. Derby survived for 34 and 23 days, respectively in the summer
and 58 and 46 days, respectively, in the winter. Survival at the lower inoculum level for S. Typhimurium and S. Derby was
19 and 16 days, respectively, in the summer and 24 days for both in the winter.
A steady increase in pH from acidic to alkaline was noted in all treatments and the change in pH tended to be negatively
correlated with survival of both Salmonella serotypes. Survival of Salmonella spp. was greatest during the winter period
when the slurry had a higher dissolved matter content.
Marešová, K. and M. Kollárová. 2010. Influence of compost covers on the efficiency of biowaste composting process.
Waste Management 30:2469-2474.
Two types of sheets were used – Top Tex permeable sheet and impermeable polyethylene sheet. The results of the
experiment show that the covering of piles with Top Tex permeable sheet does not have any significant effect either on the
temperature behavior over time in the compost or on oxygen content.
Within the experiment I, the composts consisted of cattle slurry and fresh grass matter at a ratio of 1:1. In case of experiment
II, it consisted of pig/cattle manure, fresh grass matter and chipped material at a ratio of about 1:2:1. During composting in
belt piles, aerobic conditions were ensured by means of mechanical aeration using a compost windrow turner.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Marti, R., P. Dabert, and A.-M. Pourcher. 2009. Pig manure contamination marker selection based on the influence of
biological treatment on the dominant fecal microbial groups. Appl. Environ. Microbiol. 75:4967-4974.
The partial 16S rRNA genes of Bacteroides-Prevotella, Eubacterium-Clostridiacea, Bacillus-Streptococcus-Lactobacillus
(BSL) and Bifidobacterium group isolates were monitored in pig manure during aerobic digestion. Bifidodobacterium spp.
and, to a lesser extent, members of the BSL group, were less affected by the aerobic treatment than the other two groups.
One species, Bifidobacterium thermacidophilum subsp. porcinum was not detected in samples from bovine, poultry, and
human fecal samples and it is proposed as a suitable microbial indicator of pig manure contamination.
Massé, D., Y. Gilbert, and E. Topp. 2011. Pathogen removal in farm-scale psychrophilic anaerobic digestors
processing swine manure. Bioresource Technol. 102:641-646.
Densities of the gram-positive Clostridium perfringens and Enterococcus spp. remained high (105 CFU/g) in the
psychrophilic anaerobic sequencing batch reactors.
Maule, A. 1999. Environmental aspects of E. coli O157. Int. Food Hyg. 9:21-23.
When the organism was inoculated into cattle feces at 7 log CFU/g, it remained detectable at high levels (> 5 log) for more
than 50 d. In contrast, numbers of viable E. coli O157 in cattle slurry declined from 8 log CFU/ml to undetectable in less
than 10 days.
McGee, P., D.J. Bolton, J.J. Sheridan, B. Earley, and N. Leonard. 2001. The survival of Escherichia coli O157:H7 in
slurry from cattle fed different diets. Lett. Appl. Microbiol. 32:152-155.
Slurry samples were inoculated at a level of 6 log CFU/g and stored in the laboratory at 10°C (not aerated). After 12 weeks,
a 3.5 and 5.5 log reduction was observed in slurry from cattle fed a silage and silage plus concentrate diet, respectively.
Meays, C.L., K. Broersma, R. Nordin, and A. Mazumderd. 2005. Survival of Escherichia coli in beef cattle fecal pats
under different levels of solar exposure. Rangeland Ecol. Manag. 58:279-283.
Studied E. coli die-off in cowpats shaded to different extents and concluded that moisture content was not a very useful
covariate.
Mendez, J.M., B. Jimenez, and C. Maya. 2004. Disinfection kinetics of pathogens in physicochemical sludge treated
with ammonia. Wat. Sci. Technol. 50(9):67-74.
With 20% w/w of ammonia, 7 logs of fecal coliforms, 6 logs of Salmonella spp., and 83% of viable helminth ova were
reduced in 2 h contact time. Inactivation increased dramatically when temperature was raised above 40°C.
Millner, P.D., K.E. Powers, N.K. Enkiri, and W.D. Burge. 1987. Microbially mediated growth suppression and death
of Salmonella in composted sewage sludge. Microb. Ecol. 14:255-265.
No suppression of salmonellae occurred in compost taken from 70°C compost-pile zones despite the presence and growth of
many types of microbes. With greater numbers and kinds of microbes in 55°C compost, salmonella growth was suppressed
100-100,000-fold. Salmonellae died when inoculated into compost from unheated zones (25-40°C) of piles. Results showed
that fungi were relatively insignificant suppressors of salmonellae.
No significant suppression of Salmonella growth occurred when population levels of antagonists were relatively low initially
or when microbes were inoculated simultaneously with salmonellae. Salmonellae died only in compost colonized either by
coliforms only or by metabolically active bacteria and actinomycetes. The latter occur in cured compost that is not reheated.
Processes that propose to eliminate curing or allow reheating to thermophilic ranges during curing will reduce the
development of the antagonistic microflora necessary for decline and control of salmonellae.
Moriarty, E.M., M.L. Mackenzie, N. Karki, and L.W. Sinton. 2011. Survival of Escherichia coli, enterococci, and
Campylobacter spp. in sheep feces on pastures. Appl. Environ. Microbiol. 77:1797-1803.
The initial water content of the feces and the moisture gained during periods of rehydration following rainfalls increased
survival of E. coli and enterococci and conversely, dehydration promoted inactivation. Campylobacter spp. did not grow and
were rapidly inactivated at a rate that tended to be faster at higher temperatures. Regrowth of both enterococci and E. coli
occurred in sheep feces but required a higher moisture content for the latter organism.
Murry, A.C. and L.S. Hinckley. 1992. Effect of the earthworm (Eisenia foetida) on Salmonella enteritidis in horse
manure. Bioresource Technol. 41:97-100.
Results indicate that 48 h after inoculation, the % decrease in the concentration of Salmonella (initial 5.2-5.6 log CFU/was
different in the cultures with earthworms compared to cultures without earthworms (0.4 log vs 0.1 log).
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Nicholson, F.A., S.J. Groves, and B.J. Chambers. 2005. Pathogen survival during livestock manure storage and
following land application. Bioresource Technol. 96:135-143.
E. coli O157, Salmonella and Campylobacter survived (June-December) in stored slurries and dirty water for up to 3 months
with Listeria surviving for up to 6 months. In contrast, all these pathogens survived for less than one month in solid manure
heaps (10 m3) where temperatures greater than 55°C were obtained. Following manure spreading to land, E. coli O157,
Salmonella and Campylobacter generally survived in the soil for up to one month after application to both the sandy arable
and clay loam grassland soils, whereas Listeria commonly survived for more than one month. Survival times of the
pathogens in the surface (0-30 cm) layer of the solid manure heaps were similar to the main body of the heap.
Niwagaba, C., M. Nalubega, B. Vinnerås, C. Sundberg, and H. Jönsson. 2009. Bench-scale composting of sourceseparated human faeces for sanitation. Waste Management 29:585-589.
The feces:food waste (1:0) in 78 L wooden compost reactions did not maintain temperatures greater than or equal to 50°C for
a sufficiently long period and hence was not sanitized. In that system, the counts of E. coli and Enterococcus spp. increased
between days 11 and 15.
Oliver, C.E., B.K. Magelky, M.L. Bauer, F.-C. Cheng, J.S. Caton, H. Hakk, G.L. Larsen, R.C. Anderson, and D.J.
Smith. 2008. Fate of chlorate present in cattle wastes and its impact on Salmonella Typhimurium and Escherichia coli
O157:H7. J. Agric. Food Chem. 56:6573-6583.
Results suggest that chlorate administered to cattle and excreted in wastes would have no significant secondary effects on
pathogens present in mixed wastes on pen floors. Lack of chlorate efficacy was likely due to low chlorate concentrations in
mixed wastes relative to chlorate levels shown to be active in live animals, and the rapid degradation of chlorate to chloride at
temperatures of 20°C and above.
Olson, M.E., J. Goh, M. Phillips, N. Guselle, and T.A. McAlllister. 1999. Giardia cyst and Cryptosporidium oocyst
survival in water, soil, and cattle feces. J. Environ. Qual. 28:1991-1996.
Calf feces was mixed with cysts or oocysts to yield a final concentration of 10 5 cysts or 107 oocysts/g feces. Giardia cysts
were infective for 1 week in cattle feces. For Cryptosporidium, the majority of oocysts were inactivated during the first 4
weeks of storage at 4 and 25°C, but a small percentage remained viable after 12 weeks of storage. Viability was determined
using dye exclusion and mouse infectivity assays.
Ottoson, J., A. Nordin, D. von Rosen, and B. Vinnerås. 2008. Salmonella reduction in manure by the addition of urea
and ammonia. Bioresource Technol. 99:1610-1615.
Decimal values (T90) of Salmonella in dairy cattle manure (7-8 log CFU/g) were reduced from 8.3 days in the control to 2.0
days and 0.4 days at 14°C after the addition of urea (2% w/w) and ammonia (0.5% w/w), respectively. Enterococci were
evaluated as indicators for Salmonella but significantly slower decay rate and different behavior in the material made them
unsuitable as indicators for Salmonella in manure disinfected by ammonia.
Paluszak, Z., J. Bauza-Kaszewska, A. Ligocka, H. Olszewska, and W. Philipp. 2003. Microbiological studies of
composted sewage sludge for agricultural usage. Tierarztliche Umschau 58:297.
Salmonellae did not survive for more than 28 days in compost heaps where aeration was provided by turning compost piles.
In piles where aeration was achieved by a perforated pipe system through which air was drawn, survival was longer with a
range of 29 to 158.9 days.
Paluszak, Z., J. Bauza-Kaszewska, and A. Ligocka. Fate of enterococci in composted sewage sludge. Bull. Vet. Inst.
Pulaway 48:29-32.
Survival of enterococci in forced aerated piles varied from 80 to 116 days whereas inactivation in turned piles ranged from 6
to 22 days.
Paluszak, Z., J. Bauza-Kaszewska, and A. Ligocka. 2003. Survival of Salmonella senftenberg W-775 in the sewage
sludge composting process. Medycyna Weterynaryjna 59:239-242.
The inactivation rate of S. senftenberg W-775 (8-9 log CFU/ml) varied from 0.29 to 0.36 log/day in the center and top parts
of the pile and from 0.07 to 0.08 log/day in the outer zone. The survival time calculated from the regression equation ranged
from 26.4 to 121 days.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Paniel, N., S. Rousseaux, P. Gourland, M. Poitrenaud, and J. Guzzo. 2010. Assessment of survival of Listeria
monocytogenes, Salmonella Infantis and Enterococcus faecalis artificially inoculated into experimental waste or
compost. J. Appl. Microbiol. 108:1797-1809.
Listeria monocytogenes, Salmonella Infantis and Enterococcus faecalis artificially inoculated into composts after the cooling
were not detectable after 90, 60 or 30 days, respectively. At this stage, the indigenous microflora appeared to play a
significant role in suppression.
Park, G.W. and F. Diez-Gonzalez. 2003. Utilization of carbonate and ammonia-based treatments to eliminate
Escherichia coli O157:H7 and Salmonella Typhimurium DT104 from cattle manure. J. Appl. Microbiol. 94:675-685.
It appeared that S. Typhimurium DT104 was more resistant to carbonate than E. coli O157:H7. In contrast, Salmonella was
more sensitive to ammonia than E. coli O157:H7, and suggested that the minimal ammonia concentration at which significant
bacteria reduction in manure should be at least 30 mmol/L. Based on this study, concluded that the antimicrobial
mechanisms appear to be markedly different. Concluded that the antimicrobial effect of carbonate was probably the result of
chelating of ions such as calcium and magnesium whereas it was believed that ammonia caused a rapid alkalinization of the
cytoplasm, and ultimately led to lower intracellular pH.
Pecson, B.M., J.A. Barrios, B.E. Jiménez, and K.L. Nelson. 2007. The effects of temperature, pH, and ammonia
concentration on the inactivation of Ascaris eggs in sewage sludge. Wat. Res. 41:2893-2902.
The presence of ammonia, at concentrations that may be encountered in sludges, significantly increased Ascaris egg
inactivation at 20, 30, and 40°C. At 50°C, the inactivating effect of heat dominated such that no pH or ammonia effect was
observed.
Pereira-Neto, J.T., E. I. Stentiford, and D.V. Smith. 1986. Survival of faecal indicator micro-organisms in
refuse/sludge composting using the aerated static pile system. Waste Management Res. 4:397-406.
The sludge was composted using domestic refuse as the bulking material and had a mature compost cover (100-150 mm
thick) as insulator. Sample sites were located just below the cover layer. Initial Salmonella concentrations were <100/g.
There was an initial increase in numbers during composting (1 st 5 days) and then dropped to undetectable by 7 days (sample
sites just below the cover layer).
Petric, I. A. Šestan, and I. Šestan. 2009. Influence of initial moisture content on the composting of poultry manure
with wheat straw. Biosystems Engr. 104:125-134.
Relatively high moisture contents (69%) were better at achieving higher temperatures and retaining them for longer times.
However, high moisture contents are better at achieving increased losses of ammonia.
Pietronave, S., L. Fracchia, M. Rinaldi, M.G. Martinotti. 2004. Influence of biotic and abiotic factors on human
pathogens in a finished compost. Water Res. 38:1963-1970.
Seeded Salmonella arizonae 3924 serogroup B at 5 log and enteropathogenic Escherichia coli 84M at 5 log in compost.
Both pathogens grew rapidly in sterilized compost at the different moisture and storage temperatures and their growth was
suppressed in non-sterilized compost. Pathogen inactivation was lower when compost was stored at 40% compared to 80%
moisture. Results show that the major role in the pathogen suppression was played by the indigenous microflora of the
finished compost.
Plachá, I., J. Venglovský, N. Sasáková, and I.F. Svoboda. 2001. The effect of summer and winter seasons on the
survival of Salmonella typhimurium and indicator microorganisms during the storage of solid fraction of pig slurry. J.
Appl. Microbiol. 91:1036-1043.
Salmonella typhimurium survived for 26 d in summer and for 85 d in winter/spring when present initially in pig slurry at 4
log CFU/ml. pH decreased during storage.
Pourcher, M.-M., P. Morand, F. Picard-Bonnaud, S. Billaudel, S. Monpoeho, M. Federighi, V. Ferré, and G.
Moguedet. 2005. Decrease of enteric micro-organisms from rural sewage sludge during their composting in straw
mixture. J. Appl. Microbiol. 99:528-539.
Composted in a trapezoidal-shaped pile (1.2 m high, 4.85 x 3.85 m) with two ventilation pipes and turned every month.
Salmonella was present in the 4 samples of the initial straw-sludge mixture at densities of about 4 MPN/g but was quickly
inactivated. Listeria monocytogenes and Listeria sp. were detected in one sample and in 3 samples of the fourth turning,
respectively. No differences in inactivation between 3 sampling zones probably due to monthly turning of the material and
recontamination of the zone having higher temperatures.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Puri, A. and E.G. Dudley. 2010. Influence of indigenous eukaryotic microbial communities on the reduction of
Escherichia coli O157:H7 in compost slurry. FEMS Microbiol. Lett. 313:148-154.
E. coli O157:H7 inoculated into a compost slurry (7 log CFU/ml) exhibited a 4 log reduction over 16 days at 25°C whereas in
autoclaved compost, O157 remained constant throughout the test. The survival of O157 improved significantly in the
presence of cycloheximide (targets eukaryotic species). The survival in low moisture was not improved by the addition of
cycloheximide, suggesting that in dry environments, the protists play a less significant role in pathogen reduction. No
significant differences were observed in the reduction of O157 compared with the control in the presence of the crystal violet
(targets gram-positive bacteria), amphotericin (targets eukaryotic species) , or streptomycin (targets gram-negative bacteria).
Ramos, A.P.D., C.C. Stefanelli, R.E.C. Linhares, B.G. de Brito, N. Santos, V. Gouvea, R. de Cassia Lima, and C.
Nozawa. 2000. The stability of porcine rotavirus in feces. Vet. Microbiol. 71:1-8.
After storing porcine feces for 32 months at 10°C, 11 out of 30 stool samples were still positive for rotavirus by molecular
detection. Of those 11, 5 samples demonstrated cytopathic effects in cell culture.
Redlinger, T., J. Graham, V. Corella-Barud, and R. Avitia. 2001. Survival of fecal coliforms in dry-composting toilets.
Appl. Environ. Microbiol. 67:4036-4040.
The primary mechanism for fecal coliform reduction was found to be desiccation rather than biodegradation. Solar exposure
was critical for maximal class A biosolid end products.
Reinoso, R. and E. Becares. 2008. Environmental inactivation of Cryptosporidium parvum oocysts in waste
stabilization ponds. Microb. Ecol. 56:585-592.
Sunlight exposure was the most influential factor for oocyst inactivation in waste stabilization ponds. The mean inactivation
rates of oocysts in the ponds ranged from 0.0159 to 0.3025/day.
Rimhanen-Finne, R., A. Vuorinen, S. Marmo, S. Malmberg, and M.-L. Hännin. 2004. Comparative analysis of
Cryptosporidium, Giardia, and indicator bacteria during sewage sludge hygienization in various composting processes.
Lett. Appl. Microbiol. 38:301-305.
Monitored occurrence of Cryptosporidium oocysts and Giardia cysts during six different sewage sludge hygienization
processes. No statistical correlation existed between the counts of indicator bacteria, C. perfringens, E. coli, and enterococci
and occurrence of Cryptosporidium or Giardia. In sludge end-products, Giardia cysts were detected more frequently than
Cryptosporidium oocysts.
Robertson, L.J., A.T. Campbell, and H.V. Smith. 1992. Survival of Cryptosporidium parvum oocysts under various
environmental pressures. Appl. Environ. Microbiol. 58:3494-3500.
Both isolates of oocysts stored in cow feces demonstrated an interesting decrease in permeability to DAPI over the first 33
days of the study. Results suggest that a component of feces, possibly a mucopolysaccharide, might insert into the oocysts
wall, decreasing its permeability to DAPI. This fecal component, possibly affording the oocyst further protection from
environmental stresses, might be easily lost in digestive processes so that oocysts reaching the intestine would be capable of
excystation and infection.
Ruxton, G.D. 1995. Mathematical modeling of ammonia volatilization from slurry stores and its effect on
Cryptosporidium oocyst viability. J. Agric. Sci. 124:55-60.
Ryckeboer, J., J. Mergaert, J. Coosemans, K. Deprins, and J. Swings. 2003. Microbiological aspects of biowaste
during composting in a monitored compost bin. J. Appl. Microbiol. 94:127-137.
Total microbial activity, measured with an enzyme activity assay, decreased during the thermophilic phase, increased
substantially thereafter, and decreased again during maturation. Bacteria dominated during the thermophilic phase with all
isolates being bacilli. During the cooling and maturation phase, the bacterial diversity increased, including also other Grampositive and Gram-negative bacteria. Among the fungi, Aspergillus spp. and Mucor spp.were predominant after the
thermophilic phase. Compost maturity was correlated with high microbial diversity and low activity.
Salsali, H.R., W.J. Parker, and S.A. Sattar. 2006. Impact of concentration, temperature, and pH on inactivation of
Salmonella spp. by volatile fatty acids in aerobic digestion. Can. J. Microbiol. 52:279-286.
Individually, at a dosage of 6000 mg/L, concentrations of Salmonella spp. (initial - 1.6 x 104 cfu/ml) after 24 h of exposure
were 4700, 6300 and 8700 cfu/ml for acetic, propionic and butyric acids, respectively. Increases in temperature appeared to
increase the inhibitory effects of the volatile organic acids. At mesophilic temperatures, acidic pHs resulted in a greater
inhibition of Salmonella spp.; whereas at higher temperatures neutral pHs were found to be more inhibitory.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Schijven, J.F., S.A. Bradford, and S. Yang. 2004. Release of Cryptosporidium and Giardia from dairy cattle manure:
Physical factors. J. Environ. Qual. 33:1499-1508.
The manure and (oo)cyst release rates from cow manure decreased faster than those from calf manure, and (oo)cyst release
efficiencies from cow manure were higher than those from calf manure. An effect of temperature on the release of manure
and (oo)cysts was not apparent.
Scott, L., P. McGee, J.J. Sheridan, B. Earley, and N. Leonard. 2006. A comparison of the survival in feces and water
of Escherichia coli O157:H7 grown under laboratory conditions or obtained from cattle feces. J. Food Prot. 69:6-11.
E. coli O157:H7 collected from inoculated cattle were detected up to 10 weeks longer than the laboratory-prepared culture.
This study suggests that pathogen survival in low-nutrient conditions may be enhanced by passage through the
gastrointestinal tract.
Semenov, A.M., A.A. Kuprianov, and A.H.C. van Bruggen. 2010. Transfer of enteric pathogens to successive habitats
as part of microbial cycles. Mirob. Ecol. 60:239-249.
Survival in dung was better after passage through the digestive tract of cows than after introduction of cultures into dung.
Semenov, A.V., A.H.C. van Bruggen, L. van Overbeek, A.J. Termorshuizen, and A.M. Semenov. 2007. Influence of
temperature fluctuations on Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium in cow manure.
FEMS Microbiol. Ecol. 60:419-428.
Manure was inoculated with 7 log CFU/gdw.
Stored at 4 temperatures (7, 16, 23, and 33°C) and daily oscillations with three amplitudes (0, 4, and 7°C).
Population densities were determined by direct plating.
E. coli O157:H7 survived for shorter periods of time and was more sensitive to competition by the native microbial
community than Salmonella serovar Typhimurium when inoculated into cow manure at 7 log CFU/gdw. Survival of both
pathogens significantly declined with increasing mean temperatures and with increasing amplitude in daily temperature
oscillations. The effects of temperature oscillations were more pronounced at a mean temperature of 23°C than at lower
mean temperatures. Growth of both E. coli O157:H7 and Salmonella occurred in sterilized manure compared to untreated
manure at these temperatures.
The survival period in manure ranged from <7 days for E. coli O157:H7 at 33°C to 159 days (theoretical estimation) at 7°C.
For Salmonella serovar Typhimurium, the survival period, predicted from the model, ranged from 227 days at 7°C to <21
days at 33°C. With oscillating temperatures of 7°C, the populations of E. coli O157:H7 and Salmonella serovar
Typhimurium were on average 52.6% and 39.0% reduced compared to those at static temperatures.
Sharma, R., F.J. Larney, J. Chen, L.J. Yanke, M. Morrison, E. Topp, T.A. McAllister, and Z. Yu. 2009. Selected
antimicrobial resistance during composting of manure from cattle admininstered sub-therapeutic antimicrobials. J.
Environ. Qual. 38:567-575.
Manure collected from cattle fed tylosin (TY) or chlortetracycline-sulphamethazine (TS) were placed in windrows (12 m
long, 2.5 m wide, and 1.5 m high). Windrows took a long time to reach maximum temperatures and were cooler than
overwinter composting trials reported for the region.
Shepherd, M.W., Jr., P. Liang, X. Jiang, M.P. Doyle, and M.C. Erickson. 2007. Fate of Escherichia coli O157:H7
during on-farm dairy manure-based composting. J. Food Prot. 70:2708-2716.
In trial 1, inoculated with 7 log CFU/g of E. coli O157:H7. Although the compost heaps achieved temperatures of 50°C or
above at all internal locations for at least 7 days, temperature stratification was observed. E. coli O157:H7 was detected by
enrichment through 14 days within the heaps. In trial 2, inoculated with 5 log CFU/g of E. coli O157:H7. The pathogen was
detected only through days 2, 2, and 5 at the top, center, and bottom locations, respectively. For both trials, the pathogen
survived at the heap’s surface for up to 4 months. The indicator commensal E. coli and coliforms were inactivated at a rate
similar to that for E. coli O157:H7.
Shepherd, M.W., Jr., R. Singh, J. Kim, and X. Jiang. 2010. Effect of heat-shock treatment on the survival of
Escherichia coli O157:H7 and Salmonella enterica Typhimurium in dairy manure co-composted with vegetable wastes
under field conditions. Bioresource Technol. 101:5407-5413.
In the summer, heat shocked E. coli O157:H7 and Salmonella (initial levels 6.5 – 7.5 log CFU/g) survived in compost heaps
(ca. 1.2 m in height x 2 m in width) for 7 and 2 days longer at the surface and bottom locations of the compost heaps,
respectively, than non-heat-shocked cultures.
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Sidhu, J., R.A. Gibbs, G.E. Ho, an dI. Unkovich. 1999. Selection of Salmonella Typhimurium as an indicator for
pathogen regrowth potential in composted biosolids. Lett. Appl. Microbiol. 29:303-307.
Compost from a commercial composting facility (28% biosolids) had been composting for two weeks in windrows (20 m x 4
m x 3.5 m). 600 g of sterile composted biosolids was seeded with 30 ml of 10 6 dilution of pathogen..
Growth parameters of six serovars of Salmonella and three strains of Escherichia coli in sterilized composts were compared.
Seeded Salmonella and E. coli grew rapidly, reaching population densities of more than 10 8/g after 30 h of incubation.
The isolates of S. Typhimurium showed a significantly higher specific growth rate compared to the isolates of other serovars.
Also, the maximum population density attained by S. Typhimurium was significantly higher when compared to the isolates of
other Salmonella serovars tested.
Sidhu, J., R.A. Gibbs, G.E. Ho, and I. Unkovich. 2001. The role of indigenous microorganisms in suppression of
Salmonella regrowth in composted biosolids. Wat. Res. 35:913-920.
Seeded S. typhimurium colonized rapidly in sterilized biosolids but was suppressed in non-sterilized. There was a significant
decline in the growth rate of seeded Salmonella in sterilized compost when the compost was stored, suggesting that
bioavailable nutrients declined with storage. Indigenous microflora appeared to have a significant role in suppression of
Salmonella regrowth in composted biosolids but its effect declined with compost storage. It is possible that the higher
availability of nutrients in the presence of adequate moisture and temperature results in higher activity of indigenous
microorganisms.
The regrowth inhibitory effect was found to be maximum in biosolids composting for two weeks and may be due to the
presence of regrowth inhibitory compounds, secondary metabolites, or the presence of highly active indigenous
microorganisms such as somatic Salmonella phage, which results in Salmonella cell lysis.
Singh, R., J. Kim, M.W. Shepherd, Jr., F. Luo, and X. Jiang. 2011. Determining thermal inactivation of Escherichia
coli O157:H7 in fresh compost by simulating early phases of the composting process. Appl. Environ. Microbiol.
77:4126-4135.
In the optimal compost mix (25:1 C:N), E. coli O157:H7 survived for 72, 48, and 24 h in compost with 40% moisture and for
72, 24, and 24 h with 50% moisture at 50, 55, and 60°C, respectively, following 2 days of come-up time (rate of heating up).
However, in the suboptimal compost mix (16:1 C:N), the pathogen survived for 288, 72, and 48 h in compost with 40%
moisture and for 240, 72, 24 h in compost with 50% moisture at the same temperatures, respectively. Pathogen survival was
longer, with 5 days of come-up time compared with 2 days of come-up. Overall, E. coli O157:H7 was inactivated faster in
the compost with 50% moisture than in the compost with 40% at 55 and 60°C. Both moisture and come-up time were
significant factors affecting Weibull model parameters. Our results suggest that slow come-up time at the beginning of
composting can extend pathogen survival during composting. Additionally, both the C/N ratio and the initial moisture level
in the compost mix affect the rate of pathogen inactivation as well.
Sinton, L.W., R.R. Braithwaite, C.H. Hall, and M.L. Mackenzie. 2007. Survival of indicator and pathogenic bacteria
in bovine feces on pasture. Appl. Environ. Microbiol. 73:7917-7925.
Campylobacter and Salmonella were inoculated into cow feces to give 0.6 – 2.7 x 107 CFU/gdw and 1.1 – 3.2 x 107
CFU/gdw and pats placed on unshaded ryegrass. The initial E. coli and fecal streptococcal counts in the cow pats were all
around 105 or 106 CFU/g. In contrast, the initial enterococcus counts were highly variable, ranging from over 10 5 CFU/g in
the spring to 99 CFU/g in the autumn experiment.
The temperature of the pats, soil, and air was governed by solar radiation and exhibited diurnal oscillations. The pat
temperatures were generally higher than those of the air or soil. The pat temperature probably influenced bacterial growth
when the water content was greater than 80% but at a water content of 70 to 75% counts decreased. When exposed to
sunlight, the pats quickly formed a skin, which thickened to a well-defined crust within about 48 h. Once the crust formed,
leaching losses tended to be low if subsequent rainfall is <50 mm per month,
Overall S. enterica was inactivated only slightly more rapidly than E. coli and the other indicators but C. jejuni was rapidly
inactivated in cow pats on pasture even when the water content remained above 80%.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Skanavis, C. 1994. Evaluation of composted sewage sludge based on soil amendments for potential risks of
salmonellosis. J. Environ. Hlth. 56:19-24.
Salmonella spp. were not isolated by routine analyses from samples with fecal coliform densities less than 1,000 MPN/g.
Low levels of Salmonella (detection by enrichment) were detected in the composted sludge. The distribution of salmonellae
serotypes did not suggest a strong correlation between the occurrence of Salmonella in the compost products and Salmonella
infections in the community demonstrating that the probability of infection was low.
Smårs, S., L. Gustafsson, B. Beck-Friis, and H. Jönsson. 2002. Improvement of the composting time for household
waste during an initial low pH phase by mesophilic temperature control. Bioresource Technol. 84:237-241.
An initial phase characterized by a low pH is often observed during composting of organic wastes and perhaps especially of
easily degraded energy-rich materials like household waste. Low pH phase was prolonged if the material was composted
under low oxygen conditions, i.e. 2.5 and 1% oxygen.
Soares, H.M. and B. Cardenas. 1995. Evaluating pathogen regrowth in biosolids compost. Biocycle 36(6):70-74.
Moisture, carbon availability, and microbial diversity are the key factors that regulate pathogen regrowth in compost
products. The failure of maintaining appropriate moisture content levels during the process, which promote good microbial
activity to degrade the available carbon and develop high microbial activity, can lead to production of an unstable compost
product. When moistened, unstable compost can support regrowth of pathogenic microorganisms that were not inactivated
during the process or if reinoculation occurs.
Sobratee, N., R. Mohee, M.F. Driver, and A. Mudhoo. 2008. Survival kinetics of faecal bacterial indicators in spent
broiler litter composting. J. Appl. Microbiol. 104:204-214.
Total coliforms, fecal coliforms and E. coli were rapidly destroyed while fecal enterococci were more resistant. The rate
equations showed that total coliforms, fecal coliforms, and E. coli reductions were expressed by second-order decay kinetics.
Fecal enterococci reduction followed first-order decay.
Soldierer, W. and D. Strauch. 1991. Kinetics of death of Salmonellae during thermal liquid manure disinfection. J.
Vet. Med. Series B 38:561-574.
Salmonella senftenberg 775W survived much longer than each of 12 other strains from 8 different Salmonella serovars. D60
values ranged from 47 to 138 sec depending on the type of slurry used. D values for Salmonella senftenberg were: D50 =
56.7 min, D55 = 11.5 min, D60 = 2.3 min, D65 = 0.47 min.
Stringfellow, K., D. Caldwell, J. Lee, A. Byrd, J. Carey, K. Kessler, J. McReynolds, A. Bell, R. Stipanovic, and M.
Farnell. 2010. Pasteurization of chicken litter with steam and quicklime to reduce Salmonella Tyhimurium. J. Appl.
Poultr. Res. 19:380-386.
Chicken litter was exposed to steam (soil pasteurization ) for 0, 5, 30, or 120 min. Quicklime was used at 0, 2.5, 5.0 or
10.0%. Steam alone reduced Salmonella by 3 orders of magnitude. Both steam and quicklime reduced Salmonella to
undetectable levels.
Szala, B. and Z. Paluszak. 2008. Validation of biodegradable waste composting process based on the inactivation of
Salmonella senftenberg W775. Polish J. Environ. Stud. 17:79-85.
Szejniuk, B., K. Budzinska, G. Wronski, M.M. Kostrzewa, and A. Jurek. 2011. Survival rate of Salmonella Enteritidis
in pig slurry. Rocznik Ochrona Srodowiska 13:2049-2059.
A suspension of the tested bacteria Salmonella Enteritidis was introduced into slurry placed in a glass vessel of 6 L (8 log).
Held at 4° and 20°C. Within 2 weeks, the pathogen could not be detected at 20°C whereas it took 8 weeks before it could no
longer be detected at 4°C.
Tiquia, S.M., N.F.Y. Tam, and I.J. Hodgkiss. 1998. Salmonella elimination during composting of spent pig litter.
Bioresource Technol. 63:193-196.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Tønner-Klank, L., J. Møller, A. Forslund, and A. Dalsgaard. 2007. Microbiological assessments of compost toilets: In
situ measurements and laboratory studies on the survival of fecal microbial indicators using sentinel chambers.
Waste Management 27:1144-1154.
In controlled composting experiments, thermophilic conditions were only reached when amendments were made (grass and a
sugar solution). Even then it was impossible to ensure a homogeneous temperature in the composting fecal material and
therefore difficult to achieve a uniform reduction and killing of indicator bacteria.
Regrowth was detected for enterococci, therefore, these indicator parameters may overestimate the level of other pathogenic
bacteria present in the material and can not be recommended for use as reliable indicator organisms.
Toth, J.D., Z. Dou, H.W. Aceto, S.C. Rankin, J. Vanderhoef, and C. DebRoy. 2011. Control of Salmonella and E. coli
O157:H7 in dairy manure through modification of pH and temperature. ASA, CSSA, SSSA Intl. Ann. Mtg., Oct. 1619, San Antonio, TX.
E. coli O157:H7 was more sensitive to acidification of manure than Salmonella. S. Newport completely deactivated within 6
days at pH 4.2 or less whereas E. coli O157:H7 was killed within 1 days when pH was < 4.9. A pH adjustment to greater
than 10.8 was necessary to kill S. Newport and E. coli O157:H7.
Turner, T. 2002. The thermal inactivation of E. coli in straw and pig manure. Bioresource Technology 84:57-61.
It was found that an indicator strain of E. coli was inactivated in farmyard manure, pig faeces and straw if kept at 55 oC for
more than two hours. It was, however, still viable after 72 hours at 50 oC. Coliforms grew in the compost if the process was
carried out at mesophilic (37oC) temperatures.
Results demonstrated that at 50°C, inactivation of E. coli may depend on the moisture content and the nature of the material
(E. coli was not detectable after 24 h when 10 ml broth added to 20 g pig feces compared to when 1 ml broth added to pig
feces in which populations were still at 2.9 log CFU/ml.)
Ugwuanyi, J.O., L.M. Harvey, and B. McNeil. 1999. Effect of process temperature, pH and suspended solids content
upon pasteurization of a model agricultural waste during thermophilic aerobic digestion. J. Appl. Microbiol. 87:387395.
In some cases, a ‘tail’ was apparent under thermophilic aerobic digestion conditions, possibly indicating the survival of
relatively resistant sub-populations. It is possible that agglomeration of cells and attachment to particulate materials in the
waste led to an extended heat resistance.
Whereas E. coli was more sensitive to heat at pH 8 and 60°C, there was no difference due to pH at either 55 or 65°C. An
increase in the solid content of the digesting waste caused a progressive increase in the protection of test organisms from
thermal inactivation.
Van Derlinden, E., I. Lule, K. Bernaerts, and J.F. Van Impe. 2010. Quantifying the heterogeneous heat response of
Escherichia coli under dynamic temperatures. J. Appl. Microbiol. 108:1123-1135.
The slowly increasing temperature (1°C/h) starting from 42°C results in growth up to 60°C, a temperature significantly
higher than the known Tmax. The temperature stress-sensitive subpopulation is still able to grow for ca. 3 h up to
temperatures around 45°C, after which inactivation starts. After ca. 8 h, the cell number is dominated by the temperature
stress-resistant population. Growth of the heat-resistant subpopulation is sustained up to 60°C. This study further confirms
the existence of a stress-resistant subpopulation and reveals the unexpected growth of E. coli at temperatures significantly
higher than Tmax.
van Herk, F.H., T.A. McAllister, C.L. Cockwill, N. Guselle, F.J. Larney, J.J. Miller, and M.E. Olson. 2004.
Inactivation of Giardia cysts and Cryptosporidium oocysts in beef feedlot manure by thermophilic windrow
composting. Compost Sci. Util. 12(3):235-241.
Exposure of Cryptosporidium oocysts and Giardia cysts to temperatures > 55°C for a period of 15 days appears to be an
effective method of inactivating Giardia cysts and Cryptosporidium oocysts in feedlot manure.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
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Van Kessel, J.S., Y.A. Pachepsky, D.R. Shelton, and J.S. Karns. 2007. Survival of Escherichia coli in cowpats in
pasture and in laboratory conditions. J. Appl. Microbiol. 103:1122-1127.
Natural contamination. Samples in laboratory were incubated at 21.1, 26.7 and 32.2°C. Cowpats in the field and laboratory
were subsampled on days 0, 4, 8, 12, 16, 20, and 27.
Average air temperature during the observation period was 25.8°C.
Shaded cowpats received 70 to 80% less rain than those exposed to the sun. As a result, water contents in shaded cowpats
were about 3% lower than in open cowpats. The initial water contents of cowpats on pasture were about 90% for all 3 herds.
Water contents generally decreased over time and were between 50 and 70% at the end of observation period.
Initial (day 0) E. coli concentration in the fresh cowpats varied from 6 to 7 log CFU/g dry weight. Both FC and E. coli
concentrations increased as much as 1.5 orders of magnitude both in the field and in the laboratory during the 1 st week.
Temporary increases in concentrations were observed between days 12 and 16 and days 20 and 27 corresponding to rainfall
events. The concentrations dropped below initial concentrations in all cowpats only on day 20. In shaded cowpats, the dieoff of E. coli and FC was significantly slower, and the proportion of E. coli in FC was significantly larger as compared with
nonshaded cowpats. The die-off was faster in the field than in the laboratory at similar temperatures. E. coli concentrations
in shaded cowpats were on average about 2.2 times higher than open cowpats although the field die-off rate constants were
not significantly different between the shaded and exposed cowpats.
Temperature seems to be the leading factor affecting the magnitude of the initial growth of the E. coli population in freshly
deposited bovine feces.
These results indicate E. coli are dying off more rapidly than non-E. coli FC. Consequently, E. coli are the predominant
fecal-borne bacteria responsible for microbial contamination of water at early stages of manure dissolution, although non-E.
coli FC maybe responsible for limited contamination as feces/manure age.
Van Praagh, A.D., P.D. Gavaghan, and J.L. Sykora. 1993. Giardia muris cyst inactivation in anaerobic digester sludge.
Wat. Sci. Tech. 27(3-4):105-109.
Anaerobic sludge exposures conducted at 21.5°, 37°, and 50°C produced 99.9% G. muris cyst inactivation in 15.1 days, 20.5
hr, and 10.7 min, respectively.
Varel, V.H. and J.E. Wells. 2007. Influence of thymol and a urease inhibitor on coliform bacteria, odor, urea, and
methane from a swine production manure pit. J. Environ. Qual. 36:773-779.
Viable coliform cells were reduced 4.7 and 5.9 log CFU/kg of slurry for the 1.5 and 3.0 g thymol/L (33,000 L pits),
respectively, and E. coli were reduced 4.7 and 5.0 log CFU/kg of slurry, respectively. Campylobacter was not detected in the
pits treated with thymol, in contrast to 63% of the samples being positive for the untreated pit.
Venglovsky, J., J. Martinez, and I. Placha. 2006. Hygienic and ecological risks connected with utilization of animal
manures and biosolids in agriculture. Livestock Sci. 102:197-203.
The main factors influencing die-off were temperature, dryness, and UV-light.
Vinnerås, B. 2007. Comparison of composting, storage and urea treatment for sanitizing of faecal matter and manure.
Bioresource Technol. 98:3317-3321.
The storage of fecal matter (pig manure) showed some inactivation of Salmonella at 20°C but was still detectable after 50
days. No significant correlation was found between the peak temperature and the inactivation of microorganisms.
Due to lower temperatures at parts of the reactor, approximately 5% of the material can be assumed to have a lower rate of
inactivation than the rest of the material. By turning the material 3 times when having temperatures above 50°C, a 5 log
reduction would occur.
Wang, G., T. Zhao, and M.P. Doyle. 1996. Fate of enterohemorrhagic Escherichia coli O157:H7 in bovine feces. Appl.
Environ. Microbiol. 62:2567-2570.
E. coli O157:H7 survived at 37°C for 42 and 49 days with low (103 CFU/g ) and and high inocula (105 CFU/g), respectively,
and at 22°C for 49 and 56 days with low and high inocula, respectively. At both 22 and 37°C, initially increased 1.5 to 2 log
before decreasing.
Wei, J., Y. Jin, T. Sims, and K.E. Kniel. 2010. Manure- and biosolids-resident murine norovirus 1 attachment to and
internalization by Romaine lettuce. Appl. Environ. Microbiol. 76:578-583.
MNV was stable in the biosolids and swine manure as there was no loss of infectious virus after 30 days of incubation at
20°C. For dairy manure, there was a 1 log reduction at 10 days and then remained at 4 log PFU/ml at 20 and 30 days.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
composting systems
(last updated on 4/5/2012)
Wei, J., Y. Jin, T. Sims, and K.E. Kniel. 2010. Survival of murine norovirus and hepatitis A virus in different types of
manure and biosolids. Foodborne Path. Dis. 7:901-906.
Initial concentrations of hepatitis A (HAV) and murine norovirus (MNV) in autoclaved manure and liquid dairy manure were
5 x 106 TCID50/g or /ml and 1.25 x 105 PFU/g or /ml, respectively. For MNV stored in dairy manure, swine manure, or
poultry litter at 20°C, no significant loss of viral RNA occurred over 60 days. For HAV, had approx. 1 to 1.5 log reduction
after 60 days when stored in dairy manure at 20°C. The HAV was least infective after incubation in liquid dairy manure,
with the infectious titer being below the detection limit after 10 days storage at 20°C, and at 4°C, there was 3.8 log at day 10
which decreased below the detection limit at 20 days. Alum added to the samples seemed to have no effect on MNV, but
could inactivate some HAV at both 20 and 4°C.
Weinberg, Z.G., Y. Chen, R. Pinto, and S. Sela. 2007. Fate of inoculated Escherichia coli in hay. J. Appl. Microbiol.
102:1537-1543.
The majority of E. coli disappeared from both dry and moist hay by 7-8 days after inoculation (initial inoculation at 6 log).
Wells, J.E., E.D. Berry, and V.H. Varel. 2005. Effects of common forage phenolic acids on Escherichia coli O157:H7
viability in bovine feces. Appl. Environ. Microbiol. 71:7974-7979.
Feces from animals fed corn silage or cracked corn were amended with common forage phenolic acids. When 0.5% transcinnamic acid or 0.5% para-coumaric acid was added to feces from silage-fed animals and stored at room temperature, the E.
coli O157:H7 death rate was increased significantly (17-fold and 23-fold, respectively) compared to that with no addition.
Wilkinson, K.G. 2007. The biosecurity of on-farm mortality composting. J. Appl. Microbiol. 102:609-618.
The percentage of composting material bypassing thermophilic conditions is potentially more important to the overall
efficiency of pathogen reduction than the application of any given time-temperature treatment. The percentage bypass has
been estimated by representing compost pile temperature data in cross-sections using XYZ contour fill charts and calculating
the proportion of surface area falling in any given temperature range.
Wilkinson, K.G., E. Tee, R.B. Tomkins, G. Hepworth, and R. Premier. 2011. Effect of heating and aging of poultry
litter on the persistence of enteric bacteria. Poultry Sci. 90:10-18.
Listeria monocytogenes, Listeria innocua, and Salmonella enterica serovar Agona were detected in the leachate sample
collected at the base of the turned windrow on wk 10.
Williams, A.P., K. A. McGregor, K. Killham, and D.L. Jones. 2008. Persistence and metabolic activity of Escherichia
coli O157:H7 in farm animal faeces. FEMS Microbiol. Lett. 287:168-173.
Overall populations of E. coli O157:H7 were significantly greater in piglet fecal samples than in cow and horse samples
(initially inoculated with 7.8 log CFU/ml) when stored at 20°C. Increasing organic matter was negatively correlated with
counts of E. coli O157:H7 thus increased organic matter may have stimulated greater competition.
Williams, J.E. and S.T. Benson. 1978. Survival of Salmonella typhimurium in poultry feed and litter at three
temperatures. Avian Dis. 22:742-747.
Inoculated to give ~ 7 log CFU/g. When stored at 11°C, survived for at least 18 months in chicken litter. When stored at
25°C, survived for 18 months in litter. When stored at 38°C, survived for 13 days in litter.
Xu, W., T. Reuter, G.D. Inglis, F.J. Larney, T.W. Alexander, J. Guan, K. Stanford, Y. Xu, and T.A. McAllister. 2009.
A biosecure composting system for disposal of cattle carcasses and manure following infectious disease outbreak. J.
Environ. Qual. 38:437-450.
Yang, H.E., W.Z. Yang, J.J. McKinnon, T.W. Alexander, Y.L. Li, and T.A. McAllister. 2010. Survival of Escherichia
coli O157:H7 in ruminal or fecal contents incubated with corn or wheat dried distillers’ grains with soluble. Can. J.
Microbiol. 56:890-895.
There was a time by dried distillers’ grains soluble (DGGS) interaction, where the numbers of E. coli O157:H7 in feces did
not differ after 4 or 12 h of incubation but were greater after 24 h in both 40% wheat and 40% corn DDGS as compared with
other treatments. Additionally, after 24 h, the numbers of E. coli O157:H7 were greater in fecal incubations with corn DDGS
than with wheat DDGS.
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Articles addressing specific studies exploring the fate of enteric pathogens in animal manures and
composting systems
(last updated on 4/5/2012)
You, Y., S.C. Rankin, H.W. Aceto, C.E. Benson, J.D. Toth, and Z. Dou. 2006. Survival of Salmonella enterica serovar
Newport in manure and manure-amended soils. Appl. Environ. Microbiol. 72:5777-5783.
Salmonella serovar Newport concentrations increased by up to 400% in the first 1 to 3 days following inoculation, and a
trend of steady decline followed. Most probable-number monitoring data indicated that the organisms persisted for 184, 332,
and 405 days in manure, manure-amended nonsterilized soil, and manure-amended sterilized soil, respectively.
Zaleski, K.J., K.L. Josephson, C.P. Gerba, and I.L. Pepper. 2005. Potential regrowth and recolonization of
Salmonellae and indicators in biosolids and biosolid-amended soil. Appl. Environ. Microbiol. 71:3701-3708.
Following rainfall events, significant increase in numbers was observed for Salmonellae. Most likely due to recolonization
due to contamination from fecal matter introduced by animals and not from regrowth of salmonellae indigenous to biosolids.
Compiled by Marilyn Erickson, Center for Food Safety, University of Georgia
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