Calls for clone farming to be banned were stepped up yesterday after an official study highlighted animal suffering and food safety risks.

The European Food Safety Authority found that animals involved in cloning suffer pain and ill-health linked to miscarriages, organ defects and gigantism.

It also flagged up the possibility that clones and their offspring could pass animal diseases to humans through meat and milk.

Cloned pigs: A study has found animals involved in cloning suffer ill-health

The inquiry was launched in January 2007 after the Daily Mail highlighted the fact that Dundee Paradise – the offspring of a clone – had been born on a British farm.

Last month, the Mail reported that a total of eight 'clone farm' calves have now been born on British farms. 

Frozen embryos taken from the clones of prize-winning Holstein cows in the U.S. were flown to the UK and implanted into farm animals.

Advocates claim it will allow prize-winning animals to be copied to create a new generation of animals, able to produce vast quantities of milk or lean meat.

But the report by the EFSA, set up in 2002 to improve EU food safety, said: 'The health and welfare of a significant proportion of clones have been found to be adversely affected, often severely and with a fatal outcome.'

Professor Vittorio Silano, of the EFSA, said: 'It is clear there are significant animal health and welfare issues for surrogate mothers and clones that can be more frequent and severe than for conventionally-bred animals.'

The cloning process involves taking the nucleus of cells from the ear of an animal and implanting them in an egg from a female. The fertilisation process is kick-started with an electric charge.

There are large number of miscarriages of embryos. Organ defects lead to death in pregnancy or soon after birth.

EFSA said clones are also more likely to show 'gigantism'. They are so large the only way they can be born is through caesarean section.

The study highlighted the need to find out why clones and their offspring are more vulnerable to some diseases and if these could be a food safety threat. T

he report said: 'It should be investigated whether consumption of meat and milk derived from clones or their offspring may lead to increased exposure to transmissable agents.' 

The developments in clone farming have outpaced moves by the British Government and EU to put in place a policing mechanism.

There is no system to monitor the existence and welfare of clones and their offspring. Nor is there any system to ensure that meat and milk from these animals is labelled to inform shoppers.

The final decision on whether to allow clone farming and food rests with the European Commission.

Peter Stevenson of Compassion in World Farming, said: 'Britain and the EU should ban cloning, not just farming but also food from cloned animals and their offspring because of the very serious health and welfare issues.'

RSPCA senior scientist, Dr Nikki Osborne, said: 'The RSPCA believes cloning of animals for food production should be banned on animal welfare and ethical grounds.'

Sue Davies, Chief Policy Adviser at consumer group Which?, said: 'This EFSA opinion highlights why it is far too premature to think about using cloned animals for food production.'

Director of Eurogroup for Animals, Sonja Van Tichelen, said: 'The EU is now obligated to follow its own rules. Under the general farm directive a breeding technique that causes suffering should not be allowed.'

Last night Defra said it would expect food companies or farmers to seek advice from the Government before attempting to put meat and milk from clones or their offspring on the market.