[Jacob-list] certified scrapie free

[BIDEWEE at aol.com]

Hi Betty,
In theory, the longest it would take for signs/symptoms of scrape to appear 
 in live animals is 5 years.  The current theory for transmission is  that 
scrapie is passed from mother to lambs via birth fluids.  Apparently  it's 
also possible for other animals housed in the same area to be infected  from 
the birth fluids.  
 
When you're enrolled In the voluntary scrapie program, a state vet comes  
out once a year to inspect your flock for signs of scrapie.  Enrolled  flocks 
must provide the USDA with annual records (complete with names  and contact 
info) of all incoming and outgoing sheep.   In addition, all farm born 
animals over 18 months must be  tagged and added to the flock 'inventory' and 
cause of death must be  provided for all deceased animals.  
 
To be certified in the voluntary program, a flock must go 5 years  without 
signs/symptoms of scrapie appearing in the flock and without adding any  
non-certified, unknown or suspect animals.  Rams don't affect status since  
scrapie isn't apparently transmitted through semen.  Ewes can be added from  
certified flocks without affecting status, but if they're added from 
un-enrolled  or enrolled (but not yet certified) flocks, the flock will revert back 
to the  status of the flock the ewe came from.  Example, we enrolled in the  
voluntary program in 2001 then bought our Huntsberger sheep in 2003 so our  
status reverted back to year 1 since the Huntsberger sheep weren't on the  
voluntary program.  Our flock was certified in 2008 because we hadn't  added 
any ewes from non-certified flocks in the ensuing 5  years.  
 
Obviously a live animal test would be more precise but until an affordable, 
 effective live animal test becomes widely available, this is the system 
the  USDA uses to consider a flock to be scrapie free.
 
Hope that makes sense,
Karen Lobb
bide a wee farm
_www.bideaweefarm.com_ (http://www.bideaweefarm.com) 
 
 
 
In a message dated 7/20/2010 9:15:14 A.M. Pacific Daylight Time,  
jacob-list-request at jacobsheep.com writes:

If the  only way you can tell if a sheep has scrapie is through examing its 
brain when  it's dead, how can a flock be certified scrapie free?  I'm just 
curious  as to the process.  I know that the mandatory scrapie program 
simply has  people record who got sold to whom and keep records, in case, when 
randomly  checking for scrapie, they come across a sheep that has it and can 
then, track  it back.  But I'm not entirely sure how the voluntary program 
works in  such a way that it can certify a flock scrapie-free?  All 
explanations  welcome
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