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E. COLI TRANSPORT AFTER POULTRY LITTER APPLICATION
JORGE A. GUZMÁN, GAREY A. FOX AND JOSH B. PAYNE
DEPARTMENT OF BIOSYSTEMS AND AGRICULTURAL ENGINEERING
OKLAHOMA STATE UNIVERSITY
Types of litter bacteria
• Beneficial bacteria
• Pathogenic bacteria:
- Salmonella
- Campylobacter
• Fecal indicator bacteria:
- enterococci
- Escherichia coli (E. coli)
E. coli
• Common bacteria found in nature
• Intestinal tracts of humans and warm blooded animals
• Many harmless strains exist
• Some can be pathogenic
• For example: E. coli O157:H7
– Produces powerful toxin
– Causes human infection
E. coli O157:H7 Sources• Feces or intestines of cattle
• Also found in rabbits, deer, dogs, goats, pigs, horses, poultry, sheep and wild animals
• Can survive for long periods in feces, soil and water
Transmission
• Transmitted via contaminated water, animals and other humans
• Ingestion of only a few cells can cause illness
Symptoms
• Usually occur 3-4 days after exposure
• Some show no symptoms or mild diarrhea
• Hemorrhagic colitis
• Hemolytic uremic syndrome
Land application of manure
• Questions exist regarding E. coli transport following manure application
E. Coli Field Study
• Objective: Investigate E. coli concentrations transported by surface runoff after litter application
E. Coli Field Study
• Select field with similar soil and slope
• Mixture of perennial ryegrass, tall fescue grass, bermuda grass and some Johnsongrass
Study area
Rainfall simulator
Eastern Research StationOklahoma State University
perennial ryegrasstall fescuegrassbermudagrassjohnsongrass
P1
P14
100 m
E. Coli Field Study
• 14 plots
• Treatments:
- 4,942 kg/ha (2.2 tons/ac) rate of broiler litter
- 2 control plots (no litter)
- Litter applied on small area outside of plots
• Subjected to artificial rainfall
- 2 year storm event (45 min; 2.3 inches/hr)
- 5 year storm event (30 min; 3 inches/hr)
Time (hours)
Poultry Litter Application
Rainfall Rainfall Rainfall
24 h 120 h0 h
E. coli E. coli E. coli
2 yr stormt=45 mini=58.4 mm (2.3”)/hrV=43.8 mm 1.72”
5 yr stormt=30 mini=76.2 mm (3”)/hrV=38.1 mm (1.5”)
Control 0 h 24 h 120 h
Average EMC 6.8 103 1.6 105 1.3 104 4.3 104
Maximum EMC 7.7 103 2.2 105 2.6 104 6.2 104
Minimum EMC 5.8 103 5.0 104 7.1 103 1.9 104
P-Values from ANOVA Test on Average EMCs
(95% CL)
0 h 0.053 -- 0.008 0.024
24 h 0.412 0.008 -- 0.026
120 h 0.058 0.024 0.026 --
E. Coli Event Mean Concentrations (EMC) (MPN/100 mL)
Results
• E. coli decreased at 24 h and 120 h compared to 0 h after litter application.
• In control plots, E. coli was always detected, indicating other sources of E. coli.
• Other sources may include: rodents, birds and other small mammals.
Conclusions
• Litter applications may contribute to runoff of E. coli when rainfall events occur shortly after application.
• Other sources of contamination serve as a significant component of the total E. coli load.
• As time increases after litter application, background E. coli concentrations become a larger component of total E. coli load.
SOIL BACTERIA FATE
Phylogeneticspecies- strain
Evolutionary processmanure source & conditions
External VariablestemperaturepHmoisture contentUV light
Nutrients - Substrateelectron acceptorcarbon source
Ecological Microcosm & Macrocosm antagonism (predation, host), competition, amensalism, comensalism, mutualism.
GROWTHinactivation – VBNCphysiological death
sustained population
SURFACE RUNOFF TRANSPORT OF E. COLI AFTER POULTRY LITTER APPLICATION ON PASTURELANDS: FIELD EXPERIMENTS
Investigate surface runoff transport of fecal bacteria after broadcast poultry litter application due to 2- and 5-year
storm event at 0-, 24- and 120-hr time lags between application and rainfall events
Study area
Rainfall simulator
Eastern Research StationOklahoma State University
perennial ryegrasstall fescuegrassbermudagrassjohnsongrass
P1
P14
100 m
SURFACE RUNOFF TRANSPORT OF E. COLI AFTER POULTRY LITTER APPLICATION ON PASTURELANDS: FIELD EXPERIMENTS
• Fourteen 2m by 2m pastureland plots (2 controls Plots)• Poultry litter rate application: 4,942 kg ha-1 (12 Plots)• 2-year storm event : 58.4 mm hr-1
• 5-year storm event : 76.2 mm hr-1
• Meteorological variables collected by Mesonet station
SURFACE RUNOFF TRANSPORT OF E. COLI AFTER POULTRY LITTER APPLICATION ON PASTURELANDS: FIELD EXPERIMENTS
Hyd
rolo
gica
l Re
spo
nse
2-yr Storm Event
5-yr Storm Event
0
20
40
60
80
100
0 10 20 30 40 50 60
Surf
ace
Ru
no
ff (c
m3
s-1)
Time (minutes)
Plot 3
SURFACE RUNOFF TRANSPORT OF E. COLI AFTER POULTRY LITTER APPLICATION ON PASTURELANDS: FIELD EXPERIMENTS
2-yr Storm Event 5-yr Storm Event
td=45 min; i=58.4 mm hr-1
V=43.8 mmtd=30 min; i=76.2 mm hr-1
V=38.1 mm
0.E+00
1.E+05
2.E+05
3.E+05
0
20
40
60
80
100
0.0 0.5 1.0 1.5
E. c
oli
con
cen
trat
ion
(M
PN
/100
mL)
t/td
Runoff
TL=0-hr
TL=24-hr
TL=120-hr
0.E+00
1.E+05
2.E+05
3.E+05
0
20
40
60
80
100
0.0 0.5 1.0 1.5
Surf
ace
run
off
(cm
3 s
-1)
t/td
Runoff
TL=0-hr
TL=24-hr
TL=120-hr
Control
1
1
N
i i
i
N
i
i
Q C
EMC
Q
Escherichia coli event mean concentration (EMC) based on average measured flow and E. coli concentrations
from control and litter plots.
SURFACE RUNOFF TRANSPORT OF E. COLI AFTER POULTRY LITTER APPLICATION ON PASTURELANDS: FIELD EXPERIMENTS
Event Mean Concentration
Control 0 h 24 h 120 h
Average EMC 6.8 103 1.6 105 1.3 104 4.3 104
Maximum EMC 7.7 103 2.2 105 2.6 104 6.2 104
Minimum EMC 5.8 103 5.0 104 7.1 103 1.9 104
P-Values from ANOVA Test on Average EMCs
(95% CL)
0 h 0.053 -- 0.008 0.024
24 h 0.412 0.008 -- 0.026
120 h 0.058 0.024 0.026 --
SURFACE RUNOFF TRANSPORT OF E. COLI AFTER POULTRY LITTER APPLICATION ON PASTURELANDS: FIELD EXPERIMENTSM
ete
oro
logi
cal E
xoge
no
us
Var
iab
les
Relative Humidity
Air Temperature
Solar Radiation
Control Poultry Litter
Statistically significant differences were observed in average EMCs relative to time lag between litter application and rainfall (Decreasing between 0 and 24 hr and increasing at 120 hr).
Escherichia coli was always detected in the control plots from other sources.
Bacteria survival and growth was hypothesized to depend on the location of deposited litter within the plot.
No significant differences were observed in average event mean concentrations (EMCs) relative to storm intensity.
SURFACE RUNOFF TRANSPORT OF E. COLI AFTER POULTRY LITTER APPLICATION ON PASTURELANDS: FIELD EXPERIMENTS
MAJOR FINDINGS