The Aylesbury Duck

Chap goes into the butchers to buy an Aylesbury duck, the butcher places one on the counter, the chap picks it up and sticks his finger up it's ass, . . he says to the butcher, . . "this aint an Aylesbury duck", . . the butcher takes another one off the shelf and places it on the counter, the chap does the same with his finger again, he then says, . . "this is'nt from Aylesbury either", . . he looks at the butcher and says, . . "which part of the country do you come from mate ? ", . . the butcher spun round, dropped his pants, bent over and said, . . "you tell me mate, you're the expert".