8 May 2000
BSE is spread through cowpats
By FWi staff
INFECTED cow dung contaminating pastures could be prolonging the BSE crisis in Britain, claims a leading scientist.
In Britain it has always been believed that the disease has been passed by contaminated feed or in very small number of cases by mother to calf.
But Dr Alan Dickenson, the founding director of the Neuropathogenisis Unit in Edinburgh, which researches prion diseases, has found that most infected material fed passes through the gut.
This is excreted onto pastures where it may be re-ingested by another animal, which could then become infected, suggests Prof Dickenson.
“The risk of a cow grazing pasture becoming infected is a pretty low risk, but a real risk,” Prof Dickenson told the BBC Radio 4 Farming Today programme.
Last month Chris Bostock, director of Institute for Animal Health, suggested BSE-type disease scrapie could be transmitted through infected tissue , such as the placenta at lambing time, contaminating pastures.
A fortnight ago French agriculture minister Jean Glavany announced the possibility of a mysterious “third way” of BSE infection.
In Britain it was predicted that no calves should have been born with the disease after 1996, after tighter controls were introduced.
Therefore, it was projected that the disease would be eradicated after 2001, by which time any calves with the disease would show symptoms.
Now it is believed there will be 866 cases 2001, 23 of which will be born after August 1996, reports Farming Today.
In written parliamentary answer, junior agriculture minister Baroness Hayman said no estimates had now been made beyond 2001, because figures were increasingly unreliable.
There have been calls for the government to administer the drug pentosan polysulphate which has been shown to be effective against similar BSE-type diseases.
Peter Smith of the Spongiform Encephalopathy Advisory Committee (SEAC) said research was looking at this, but that it was premature to think of administering it to thousands of animals.
He said there was no evidence that environmental contamination was extending the BSE crisis, but admitted it was also difficult to prove this is not happening.