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The Rural Voice, 2001-05, Page 51Farmers pack hall to hear about Foot and Mouth The level of concern over the potential for Foot and Mouth Disease (FMD) to enter Canada was evident when a standing -room -only crowd packed the Elmwood Community Centre, April 17 to hear speakers give the latest information on the disease. About 300 farmers attended the last of a series of six meetings across the province what drew more than 2000 people, far more than the expected attendance of 800, said Cathy Lennon, general manager of the Ontario Sheep Marketing Agency who chaired the meeting. John Forsyth OMAFRA program manager of cattle and swine, pointed out FMD is much more widespread than just the current outbreak affecting most of Asia and Russia, Targe parts of Africa and major countries in South America. With modern travel it takes only six hours to get from some infected countries to North America instead of a lengthy boat trip when FMD last affected Canada in 1952, he said. As well, many Ontario farmers have close ties to European countries that are affected by the current outbreak. Dr. John Derbyshire, who taught virology at University of Guelph explained the virus that causes the disease is among the smallest of viruses and is more resistant to environmental conditions, making it perhaps the most contagious of all animal viruses. It takes only 20 particles of the virus to infect an animal. It's RNA -based instead of DNA - based, which means it changes more rapidly, Derbyshire said. Indeed the virus at the end of an epidemic may be different than the virus that began it. Infected animals start shedding the virus before they show any of the symptoms, which makes it hard to prevent the spread of the disease. Animals are infected by inhaling or ingesting the virus, Dr. Derbyshire News said. (Pigs usually get the disease through feed, cattle and sheep by inhaling.) The virus multiplies in the throat and spreads through the blood stream. It causes blisters in the mouth and between the toes. Sheep and goats have relatively mild versions of the disease so it's often hard to tell they have it, but they can multiply the virus and give it to other animals. In Britain the disease was spread by shipment of sheep from infected parts of the country to non-infected areas. Dr. Rob Tremblay of Boehringer Ingleheim added that cattle are most infected by the disease with pigs next most susceptible. Cattle will show a loss of milk production, a high fever and depression. They develop blisters in their mouths that burst, turning to painful sores that make them salivate. They can have blisters on the teats. On their feet they develop blisters and sores between their toes and around the coronet with soreness out of proportion to the size of the sores. More than 90 per cent of cattle survive, but FMD is so debilitating it makes raising the animal uneconomic. Pigs suffer a sudden fever and depression with blisters on their snout and tongue. The sores on their feet may make it too painful for them to get up. They may be squealing and lame. Sheep show more subtle symptoms though they may have a sudden onset of lameness and be reluctant to get up, choosing to "dog sit" on their haunches instead. There may also be blisters in the mouth but they are Tess conspicuous. Sheep in Britain showed a listlessness and were off their feed. Sudden death of lambs from heart failure was also experienced. With FMD so widespread around the world, farmers need to be vigilant against the spread from more than just Britain and European countries, Tremblay said. The FMD virus is unusual in that it can survive for long periods without a host. It can live for up to 20 weeks in stored hay, for instance, which is one reason why feed and hay are also destroyed on a farm where there has been an outbreak. It can survive 14 days in a cattle stall, for 39 days in urine and for weeks to months in manure (longer in a pit, shorter in a manure pile). It can survive from a few days to a few weeks in soil and survives freezing and refrigeration, but not heat, which means it can be killed by pasteurization. Infected animals shed the virus in all bodily fluids and it can be carried in the meat of infected animals. It can spread up to 60 km overland in the wind and 300 km by sea. Yet for all this hardiness, it can be killed by weak alkaline or acidic solutions like a 1:1 ration of vinegar and water. Farmers should protect their farms by increasing biosecurity, Tremblay advised. "The first line of defence on your farm is you," he said. Post warning signs asking people to check with you before entering your property. Tell people where they can contact you if you need to do business so they won't enter your premises. Don't be afraid to ask all visitors if they have visited a country where FMD has been found. If the answer is yes, ask people to come back in two weeks. That way the low possibility the person might actually have been in contact with the disease in another country will be reduced even lower. Visitors should have clean boots and coveralls. It's probably best to keep overalls and inexpensive rubber boots for such occasions, Tremblay said. You might consider using a footbath but it's really more a statement about your concern for biosecurity than it is an effective solution, he said. While the prime focus of biosecurity now is FMD, it will also help protect your farm from other diseases that are known to exist in Canada, he said. If FMD is found on your farm, don't leave the farm, he said. If you call your vet and he diagnoses the disease, he shouldn't leave your farm either. You or the vet must call the Canadian Food Inspection Agency's Animal Health and Production Program. MAY 2001 47