Researchers claim to have found a link between bacteria in cow's milk and Crohn's disease. But it appears Ottawa is doing little to ensure milk safety.

Close to 100,000 Canadians suffer from Crohn's disease, a debilitating condition that causes inflammation of the bowels. Its symptoms include severe weight loss and pain.

A growing number of scientists believe that Crohn's disease is caused by a bacteria found in dairy cattle that may be transmitted to humans through milk.

At one of Britain's largest hospitals, chief surgeon Dr. John Hermon Taylor, says Crohn's is caused by M.A.P., short for myco bacterium paratuberculosis, which is also called Johne's disease.

According to Taylor, the disease is being transferred through milk from infected cows to humans.

The Canadian Food Inspection Agency has been monitoring Johne's disease for years. In its most recent study, obtained by CTV News, the number of infected dairy herds had risen.

In Ontario, over 47 per cent of herds had at least one animal test positive for Johne's disease. And in the Maritimes, the numbers were worse: over 51 per cent of herds in P.E.I. had the disease, 62 per cent in New Brunswick, 72 per cent in Nova Scotia.

The government admits its testing is flawed.

"If you had 10 animals infected and you applied the test, you might expect to pick out four of them, the other six would walk away and you wouldn't know they were infected," says Dr. John Kellar of the Canadian Food Inspection Agency.

Canada's dairy industry -- which has has some of the toughest standards in the world -- dismisses the claims.

"In fact the methods used in the dairy industry are so good that there has never been a sample of Canadian milk that has shown to have this bacteria in it," says Helen Bishop-MacDonald of the Canadian Milk Producers Association.

The problem is, according to Canadian Food Inspection Agency, its test to determine the presence of Johne's disease in milk which isn't very accurate.

"Governments are reluctant to recognize there is a problem. They need a new professor with a new problem, like a hole in the head," says Dr. Taylor.

CTV News requested information from Health Canada on studies the department has done linking Crohn's and Johne's. So far, there has been no reply.

But sources inside Health Canada tell CTV News it's never been studied. The only study in canada is being done by a private lab, hired by the dairy industry.