nachum@uiucdcs.CS.UIUC.EDU (11/17/85)
Arukh Hashulkhan, Yore Deah, loc. cit., agrees that 1/60th is "batel". Rambam omits any mention of meat-fish prohibition. Magen Avraham on Shulkhan Arukh, 273:1, says that "in these countries" one doesn't worry about such things.