8 August 1997

Selective cull for extension?

MAFF is considering extending the selective cull to take account of maternal transmission of BSE.

It is believed that up to 11,000 animals could be slaughtered at a cost to the Treasury of £16m, although government insisted that no decisions had yet been taken.

The possible cull extension follows a recommendation by the BSE advisory committee, SEAC, after it considered the latest maternal transmission evidence. While culling some calves born to cows that subsequently contracted BSE would have only a small effect on cutting future BSE cases, SEAC nevertheless advised government to consider it.

Recently released research showed that calves born in the last two years before the dam developed BSE were more likely to develop the disease.

Christl Donnelly, of Oxford University, said that although figures varied, between 5 and 10% of calves born to dams close to BSEonset were clinically infected with the BSEagent.

The Oxford team confirmed that the UK was likely to have about 7,000 cases of BSE between 1997 and 2001, though a further cull could reduce the figure slightly.

Team member Neil Ferguson called for more research on horizontal transmission of BSE within herds, after discovering that cows from larger herds were more at risk of BSE infection than those from smaller herds.

Dr Ferguson called for government to release data on feed records from farms with BSE. But he said MAFF had not as yet provided information due to legal implications of identifying poor practices at feed mills.