ON 1st September 1978 a Statutory Instrument that had been issued by the Minister for Agriculture, Fisheries and Food came into operation : (Warble Fly (England and Wales) Order 1978.- S.I. 1978 No. -1197).
For the stated purpose of eliminating Warble Fly, this required all cattle to have their backs and heads treated with a powerful organophosphate nerve poison.
Other countries in Europe used the same organophosphate nerve poison to eliminate the warble fly, but under different conditions. For every poison there is a threshold level below which symptoms do not develop, and with the exception of Switzerland and Britain the doses were kept below the threshold level. Switzerland and Britain used oil to increase absorption of the poison, and in Switzerland a dozen or so animals developed the symptoms of BSE. The oil had raised the absorption dose to just above the threshold. But in Britain a dose four times the recommended dose had been used, with the result that large numbers of cattle developed BSE.