 The reason for this is explained by Moe & Larry, stating that Curly's father was a rat.The kind of cheeses that Curly calls for are roquefort, camembert, and limburger; all three of which are known to have highly pungent aromas.An external stimulus — as with Curly spotting the mouse — that causes him to go bonkers was also used as a plot element in "Punch Drunks", "Grips, Grunts and Groans", and "Tassels in the Air".