Fate and Transport of Zoonotic Bacterial, Viral, and - The Pork Store ...

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Fate and Transport of Zoonotic Bacterial, Viral, and Parasitic Pathogens during Swine Manure Treatment, Storage, and Land Application
pathogens on plant surfaces is limited; recent outbreaks
of enteric disease related to consumption of produce,
however, have increased research on this topic. The
survival of swine manure zoonotic pathogens on plant
surfaces is of interest. Hutchison and colleagues (2005b)
found that when experimentally inoculated pig manure
slurry was applied to fescue grass pasture, Lysteria
monocytogenes was detected for 63 d, E. coli O157 for 32
d, and Salmonella strains and Campylobacter jejuni were
detected for 16 d. When farmyard manure from pigs
was applied to the same grass pasture, L. monocytogenes
and E. coli O157 survivals were the same, but the
Salmonella strains and C. jejuni survival increased to
32 d (Hutchison et al. 2005b). Using Listeria innocua
and Clostridium sporogens as surrogates of pathogenic
bacteria, Girardin and colleagues (2005) found that
C. sporogens spores survived very well in the soil with
under a 10 CFU/g of soil decrease after 100 d and were
detected on parsley grown in that soil at between
100 and 1000 CFU/g throughout cultivation. On
the other hand, L. innocua decreased from 4.0 × 10 5
to 32 d for Listeria, and 4
and 16 d for Campylobacter, in sandy arable soil and
clay loam grassland soil, respectively. These pathogens
tended to survive longer in the clay loam soil than in
the sandy arable soil. Monitoring Enterobacteriaceae
in clay loam soil with swine manure applied over a
3-yr period, de Freitas and colleagues (2003) found that
Enterobacteriaceae concentrations tended to increase
with increasing rates of manure application. Average
Enterobacteriaceae concentrations were different
across the 3 yr (0.4 × 10 3 CFU/g soil in Year 1, 5.4 × 10 3
CFU/g soil in Year 2, and 0.7 × 10 3 CFU/g soil in Year 3,
averaging counts from 150 and 300 kg nitrogen/hectare
application rate plots).
Incorporation and timing of incorporation of
swine manure into arable sandy loam soil in spring
or winter altered the survival rate of enteric bacterial
pathogens (Hutchison et al. 2004). Immediate
incorporation with spring application of liquid swine
manure increased the time for a log reduction of
Salmonella sp. (2.44 versus 1.89 and 0.79 d), E. coli O157
(4.89 versus 0.97 and 1.76 d), Listeria sp. (1.13 versus 0.66
and 0.84 d), and Campylobacter sp.(1.03 versus 0.63 and
2.26 d for immediate versus delayed and unincorporated
manure). The reduction times were slightly different
with winter application: Salmonella sp. (5.20 versus
2.00 d), E. coli O157 (1.86 versus 1.54 d), Listeria sp.
(1.71 versus 1.21 d), and Campylobacter sp. (1.14 versus
0.92 d for immediate versus unincorporated manure).
Results were similar for farmyard manure (feces and