We were delighted to hear the Government's Chief Medical Officer, Sir Liam Donaldson, is calling for the organ shortage crisis to be solved through the use of an opt-out policy rather than the opt-in (donor card) currently operating (and failing).

Not only is this great news for human health, but it should also mean a reduction of suffering for animals in UK laboratories.

Research on animals, including monkeys and pigs, to explore their potential as organ donors - known in the trade as xenotransplantation - is responsible for some of the most horrific examples of vivisection one could find - and still goes on in the UK.

Not only does this research cause immense suffering and, ultimately, death for the animals involved, it has been a monumental failure. Differences in the size of organs, acute rejection due to species differences and the risk of transferring viruses have meant that the promises for those needing organs have not come anywhere close to being fulfilled and are unlikely ever to do so.

The BUAV (British Union for the Abolition of Vivisection) has been calling for the opt-out system for almost ten years, since our joint report with Compassion in World Farming: "Animal Organs in humans: uncalculated risks and unanswered questions", was published.

We are pleased the medical establishment is now supporting this, and we urge it and the Government to make sure this becomes a reality.

Dr Katy Taylor, Scientific co-ordinator, BUAV, Crane Grove, London.