"Canadian investigators have identified... the probable source of recent cases of mad-cow disease [3] in North America," reports the Wall Street Journal. Canada imported 192 cattle from Britain in the 1980s. After one of the British cows tested positive for mad cow disease in 1993, Canadian officials tried to "remove" them from domestic herds. But 68 cows were missing, "most likely because they already had been slaughtered." Canada's Food Inspection Agency concluded that "the infected U.S. dairy cow and a Canadian beef cow diagnosed" with mad cow disease last year "most likely" ate feed from at least two separate mills contaminated with rendered meat from the missing British cattle. If true, this scenario suggests more cases which "may just now be surfacing."