BRITISH COWS Together with country mansions, gentlemen and ladies on horses and sweeping rural vistas, cows are a staple feature of the classical picture of Britain. They moo in the meadow, stand by the riverside swishing their tails and amble back from the fields when day is done. Their meat gives its name to everything from the Beefeaters at the Tower of London and 'Beefy' Ian Botham to the blue-blooded Beafsteak Club. Now, they are threatened with mass destruction; the cattle industry is quaking in its wellington boots and the government of John Major has been severely shaken. Hong Kong - and dozens of countries around the world - have banned British beef. Burger chains have stopped using the meat as panic swept Britain; one scientist said up to half a million people might die each year from the sinsister-sounding Creutzfeldt-Jakob Disease which has now been linked to the dreaded bovine spongiform encephalopathy (BSE), or 'mad cow' disease. British farmers, British beef-eaters - and, indeed, British cows - might wonder what they have done to deserve this raging storm descending on them. BSE has barely been seen in other countries. So why has it hit so many British cows? Most people think that BSE came from sheep infected by the scrapie illness. In Britain, much of the meal fed to cows is made from sheep carcasses. The speculation is that some of these carcasses were of sheep with scrapie; as infected sheep were fed to cows, they could have developed BSE. Then, when these cows died, their remains were used to make more meal, which was duly fed to other cows. Thus the disease spread. There are few countries outside Europe where sheep get scrapie and which also raise large numbers of cattle. Within Europe, few countries rendered down carcasses for meal at low temperatures, as is done in Britain. And few countries have gone so far as to make around five per cent of their cattle rations from meat and bone meal. So British cows may never have had a chance of escaping from BSE. The cattle were also badly served by the politicians elected by their owners. An expert committee warned the British Government 15 years ago that low temperatures in turning carcasses into meal could be dangerous. This was six years before the first case of BSE. Other European countries which suspected that animal meal might be spreading BSE banned the process. France and Ireland destroyed all animals in any herd that has seen a case of BSE. In Britain, the government banned the use of cows and sheep to feed other cows and sheep in 1988, and insisted on the slaughter of infected animals and the destruction of their milk. But the ban has not been fully enforced. Farmers, who often have a few months' supplies of meal, still had an incentive to get rid of it in the bellies of their cows. Even now, at the back of barns, there could be contaminated feed. Worse, with so many unusable remains of cows and sheep around, feed-makers may have been tempted to smuggle them into food. Nobody knows how much infected material was illegally included in meal. Some believe that offal has continued to be incorporated until recently. That would explain why the BSE epidemic in Britain has still not been brought under control. Though it has peaked, cases are being reported at the rate of over 70 a week. If meal is still being infected, that is bad enough. But if the problem lies elsewhere, then the implications are equally worrying. Any infection in younger cows - and there have been over 23,000 cases since July 1988 - could mean either that the disease can be passed from cow to calf, or that it persists in the soil. Both these possibilities seem highly unlikely; of all such diseases, only scrapie behaves in this way. Still, they cannot be ruled out because contaminated feed has obscured investigations into why young cows died. As a result, doubts will remain about the policy of culling Britain's cattle. To eradicate the British herd could cost GBP15 billion (about HK$177 billion). The cull would certainly reduce the incidence of BSE; whether it would restore consumer confidence is less certain. Consumers are worried whether beef is safe to eat. Steak almost certainly is. The government has rightly pointed out that muscle (including meat) does not seem to carry BSE, and experiments have not yet detected any such infection. The danger lies in eating pies, burgers and sausages, which might contain bits of infected brain or spinal cord. Beef is safer than it was before the government acted. But it is impossible to be sure that butchers are keeping muscle separate and uncontaminated. It is also impossible to prevent a few infected animals ending up in slaughterhouses. Even if farmers send no ailing cows to market, some animals may be infected without showing symptoms of BSE. Abattoirs have been prosecuted for ignoring the rules, and even honest slaughterhouses are messy places. Only last November did the government prohibit the stripping of meat from cows' back-bones. Mad cow disease may not yet be out of the human food chain. And one thing is certain - nobody in Britain will look at a cow in quite the same old way for many years to come.