Phrase attributed to 1930s movie star Carole Lombard after being exposed as having an adulterous affair with Clark Gable.
"At a hastily called press conference, the exasperated Lombard allegedly shouted, 'Cock-a-doodle-do! Any cock will do!' out of frustration.
"Needless to say, due to the times, none of those present printed her words, but bad blood continued between Lombard and an outraged Louella Parsons until Lombard's death."
-- Jim Bacon, "Gable & Lombard: A Romance Made in Hollywood" (Parade Magazine, November 25, 1963)
While our lifespan is the number of years we will live, our healthspan is the number of healthy years we will have and our sexspan is is the number of years we will continue to be healthy enough to continue having an active sex life.
A lighthearted reaction upon receiving disappointing news of some sort. Usually something that isn't a particularly a big deal, esp. when it primarily affects someone else - sort of a mild schadenfreude. Sometimes doubled or tripled, and possibly said in a sing-songy voice for added comedic effect to imitate a muted trumpet, which is how the meme originated.