"Farmer has problems with hes cock and ass" joke

A city man decides that he has had enough of urban life and wants to start a farm. He doesn't have much money, though, so he goes to see an old farmer to get his start.
"I'd like to buy a chicken and a rooster," he says.
"Well, young feller," says the farmer, "I reckon that'd be okay. But out here in the country we call' em a pullet and a cock."
"Okay then," says the guy, "I'll take a pullet and a cock."
"Hey, what about a donkey?" says the city guy.
"Well sure," says the farmer,"but out here in the country we call them asses. All I got is an stubborn old mule out back. He stops alot and he'll only go again if you scratch' im."
"That's fine," says the guy. He pays the farmer and heads off down the road. A little while later, the mule stops in the middle of the road. No matter what the guy does, he won't go. Then he remembers to scratch it, but he can't put his chickens down, or they'll run off.
Shortly, a woman comes down the road. She sees him and stops.
"Can I help you?" she says.
"Oh yes," said the guy, "could you hold my cock and pullet while I scratch my ass?"
She slapped him and took off.