I think someone must have altered the song "seven drunken nights" along the way, as the original words are not quite as catchy.
'Why, you old cuckold, blind cuckold,         can't you very well see?
         These are three milking-cows,         my mother sent O me.'
         'Heyday! Godzounds! Milking-cows with bridles and saddles on!
         the like was never known!'
         Old Wichet a cuckold went out, and a cuckold he came home.
(http://www.sacred-texts.com/neu/eng/child/)
Interestingly "Radio Telefis Eireann refused to play the song, due to its "questionable" content (1967)"
john