Defra has rejected Soil Association calls to combat the spread of E.coli on dairy farms by limiting the use of antibiotics.

The organic body this week called on the Government to issue guidelines limiting the veterinary use of the most modern penicillin-type antibiotics following the discovery on a dairy farm this year of a mutant strain of antibiotic-resistant E.coli that can cause severe food poisoning.

However, Defra said it was closely monitoring the farm in question and did not believe that further action was necessary at this stage. "Advisory groups have concluded that no additional precautions or on-farm restrictions are warranted," a spokeswoman added.

An NFU spokesman echoed Defra's view that E.coli bacteria are killed off by normal pasteurisation of milk and are susceptible to normal cleansing and disinfection methods.