PO-248: TSE infectivity survives burial for five years with little
reduction in titer
Allister Smith, Robert Somerville, Karen Fernie The Roslin Institute and
R(D)SVS; University of Edinburgh; Edinburgh, UK
BSE infected animals, BSE-contaminated materials and other sources of TSE
(prion) infection, such as carcasses from scrapie infected sheep, CWD infected
deer and cadavers of individuals infected with CJD may all end up in the
environment through burial or other methods of disposal. They may continue to
act as a reservoir of TSE infectivity if cattle or other susceptible animals
were to be exposed to these sources in the future. In order to address these
concerns, we performed two large scale demonstration experiments under field
conditions which were designed to mimic some of the ways by which TSE infected
materials may have been disposed of. The project examined the fate of TSE
infectivity over a period of five years in two scenarios; when the infectivity
was contained within bovine heads and when the infectivity was buried without
any containment. Two soil types were compared: a sandy loam and a clay loam. We
used the 301V TSE strain which was derived by serial passage of BSE in VM
mice.
TSE infectivity was recovered from all the heads exhumed annually for five
years from both types of soil, with little reduction in the amount of
infectivity throughout the period of the experiment. Small amounts of
infectivity were found in the soil immediately surrounding the heads, but not in
samples remote from them. Similarly there was no evidence of significant lateral
movement of infectivity from the buried bolus. However large amounts of TSE
infectivity were recovered at the site of burial of both boluses. There was
limited vertical upward movement of infectivity from the bolus buried in clay
soil and downward movement from the bolus buried in sandy soil.
Now that these experiments are completed we conclude that TSE infectivity
is likely to survive burial for long periods of time with minimal loss of
infectivity and restricted movement from the site of burial. These experiments
emphasize that the environment is a viable reservoir for retaining large
quantities of TSE infectivity, and reinforce the importance of risk assessment
when disposing of this type of infectious material.
meanwhile, back at the ranch with larry, curly, and mo at USDA ET AL ON BSE
ALABAMA STYLE
Epidemiology Update March 23, 2006
As of today, 13 locations and 32 movements of cattle have been examined
with 27 of those being substantially completed. Additional investigations of
locations and herds will continue. In addition, state and federal officials have
confirmed that a black bull calf was born in 2005 to the index animal (the red
cow). The calf was taken by the owner to a local stockyard in July 2005 where
the calf died. The calf was appropriately disposed of in a local landfill and
did not enter the human or animal food chain. http://www.aphis.usda.gov/newsroom/hot_issues/bse/bse_al_epi-update.shtml
> The calf was appropriately disposed of in a local
> landfill and did not enter the human or animal food chain.
well, back at the ranch with larry, curly and mo heading up the USDA et al,
what would you expect, nothing less than shoot, shovel and shut the hell up. no
mad cow in USA, feed ban working, no civil war in Iraq either.
SNIP...SEE FULL TEXT ;
meanwhile, back at the ranch with larry, curly, and mo at USDA ET AL ON BSE
ALABAMA STYLE
Thursday, February 17, 2011
Environmental Sources of Scrapie Prions
Friday, February 25, 2011
Soil clay content underlies prion infection odds Soil clay content underlies prion infection odds
Saturday, March 10, 2012
CWD, GAME FARMS, urine, feces, soil, lichens, and banned mad cow protein feed CUSTOM MADE for deer and elk
Friday, May 18, 2012
Update from APHIS Regarding a Detection of Bovine Spongiform Encephalopathy
(BSE) in the United States Friday May 18, 2012
Friday, May 25, 2012
R-CALF USDA’s New BSE Rule Eliminates Important Protections Needed to
Prevent BSE Spread
Saturday, May 26, 2012
Are USDA assurances on mad cow case 'gross oversimplification'?
TSS
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