AT an American government research centre in Beltsville, Maryland, Dr Bob Wall peered disconsolately at the oddly shaped piglets floundering in their straw and sighed. The experiment was finished and he knew it. Dr Wall had staked his reputation on the creation of a 'Schwarzenegger pig' that would have put him in the vanguard of a farming revolution for the 21st century. The experimental animals' rapid early growth had promised so much - but now they were fading fast. For Dr Wall's team at the Department of Agriculture's Gene Evaluation and Mapping Laboratory, it was the second such trial to end in frustration and failure. The first Beltsville pigs, their growth boosted by cow genes, went lame with arthritis at an early age. They had heart problems and bulging eyeballs. For the second experiment, a suspected chicken cancer gene was introduced into another batch of piglets. The gene made their hams and shoulders grow big and meaty; but by the time they were three months old their front and rear legs barely supported them. 'Some of the animals just got weak and then they couldn't stand up,' said Dr Wall. 'If you looked at the muscles you saw some of the beneficial effects. The muscles were getting larger. But you also saw conditions that were akin to degenerative diseases that are seen in humans.' This is the brave new science of 'transgenics': taking sequences of DNA and either altering them and putting them back into the same species or, more controversially, introducing them into a different species. The pigs are not alone. Cows, sheep and chickens are being experimented on as the farmyard is dragged into the transgenetic age. Will consumers balk when they realise that the food on their supermarket shelves has been genetically engineered? Or will the benefits of this new science outweigh the potential for repugnance? The transgenic revolution, though, is already well under way. In Canada, scientists have come up with a transgenic salmon that grows to many times its normal size. In Britain, transgenic technology is being applied experimentally to chickens following the success of Israeli researchers who have used genetic manipulation to make 'naked neck' broilers with 40 per cent fewer feathers. Because they are cool, they eat more, put on weight faster and go for slaughter sooner. Having changed the physical make-up of animals with varying degrees of success, scientists are looking forward to the day when they can alter behaviour. Already transgenic turkeys have been hatched with an artificial stretch of DNA in their sperm and ova. If all goes to plan, production of the hormone responsible for broodiness will be blocked in the turkeys' offspring. They should lay up to 20 per cent more eggs. Dr Wall, undeterred by the furore surrounding his pigs, has even more startling ambitions for this 'exquisitely sophisticated' science. It will not be long before the genes that make bears hibernate are identified, he says. By introducing them into sheep and cows, scientists could create partially hibernating livestock, saving a fortune on winter feed. He even foresees a 'third sex' of cattle, sheep and swine genetically engineered to prevent the development of testicles and do away with the time-consuming business of sexing and castrating millions of farm animals. How should we view such prospects? According to market research for the food industry, consumers increasingly favour more 'natural' products and a less intensive style of farming following the scandals and scares of recent years. Scientists, however, believe that the technology is unstoppable, that the fruits of genetic engineering are about to form a substantial part of our daily diet which will benefit humans and animals alike. Tim Lang, a professor of food policy in Britain, predicts that the profit motive will drive biotechnological initiatives forward at an ever accelerating pace. 'We are being treated with total disdain by the food industry,' he said. 'This is a juggernaut driven by pursuit of market share, when the public is increasingly saying: 'Actually, all we want is decent food.' ' In America, consumers have got used to milk from cows treated with BST, a genetically engineered growth hormone still banned in Europe. Disease-resistant crops in the offing will reduce the need for many pesticides. Some scientists see signs of a gradual acceptance of the new genetics in farming and believe that, in time, consumers will welcome transgenic animals. Professor Avigdor Cahaner, the Israeli geneticist who produced 'featherless' chickens, says such advances are essential to feed the hungry, growing populations of many Third World countries. Others claim there is little difference between 'unnatural' animals resulting from selective breeding, such as Belgian blue cattle that have to be delivered by Caesarian section because they grow so large in the womb, and the products of genetic engineering. Norman Maclean, a British professor of genetics, has made transgenic fish that are sterile, to prevent contamination of wild populations. 'I think many breeds of cattle and sheep, and particularly some dogs, should never have been developed. They don't make satisfactory animals,' he said. While changing animals' behaviour genetically could lead to greater exploitation, scientists say they cannot be responsible for all the consequences. 'We see ourselves as offering options for the future,' said Peter Sharp, a professor of animal physiology who has developed transgenic chickens in laboratories near Edinburgh. 'Whether these are taken up will be a political rather than a scientific decision.'