What joke did Barney tell Lily?

A classic animal joke. Two frogs fell in love. After getting married, they gave birth to a clam. When the male frog saw this, he was furious and said: Bitch, what’s going on? The female frog cried and said: His father, before I met you. I've had plastic surgery. The little donkey asked the old donkey: Why do we eat hay every day, while the cows only eat concentrated feed? The old donkey sighed: We men can't compare, we rely on running errands to make a living, others rely on their breasts