The Tale of Cock and Balls

I'll tell the tale of Cock and Balls
It's one you'll want to know
When a fight would happen
Cock would always take the blow

They lived together, would not part
They were the best of friends
Swore allegiance to each other
Until old and wore depends

Exploring  highest mountain tops
And caverns  dark and damp
Cock did the spelunking
 Balls stayed out to guard the camp

For many years they traveled
To places that were nice
When they enjoyed the thrill of it
Might come there once or twice

They got old together
Travels difficult to start
Cock got soft and out of shape
Balls could not do his part

They ended all their travels
Getting home with man in boat
Cock an ancient crowing rooster
And Balls a staid old mountain goat

Did you enjoy this story
Once you found the ending out?
Or did you know from the beginning
What this story was about?