Nine American ranchers from the largest U.S. cattlemen's group are scheduled to arrive in Alberta on Monday to scrutinize Canadian safeguards against the spread of mad cow disease as the two countries move toward normalizing the cattle trade after two recent cases of the illness.

The visit by the National Cattlemen's Beef Association comes as Canadian investigators look into the country's third ever case of the brain-wasting disease, according to Dow Jones newswires. The case was the second since U.S. officials announced last month that the border would be reopened in March to Canadian beef exports.

The cattlemen hope to "get as much information as they can so our cattlemen members can make a good decision about reopening trade with Canada beyond the product under 30 months of age," said Kim Essex, a spokeswoman for the group, describing the four-day visit as a fact-finding mission.

The delegation's trip includes visits to feedlots, slaughterhouses, rendering plants and meeting with government officials.

The latest case was diagnosed in a cow born after Canada had imposed a 1997 ban on certain types of feed thought to transmit the illness. This makes this case more serious than the others because the cause could be much more difficult to trace.

While Canada's agriculture minister said no part of the animal made it into the human or animal food chain, the case heightened worries among some American ranchers already uneasy over the safety of Canadian beef. They are also concerned that the new imports would pressure domestic beef prices - a worry Canadian ranchers say is overblown.

"Our industry is small enough that we're not really a threat," said Darcy Davis of the Canadian Cattlemen's Association, which is co-sponsoring the visit.