Mad Cow

A female TV reporter arranged for an interview with a farmer, seeking the main cause of Mad Cow disease.
The lady:
"Good evening, sir. I am here to collect information on the possible source of Mad Cow Disease . Can you offer any reason for this disease?"
"Do you know that a bull mounts a cow only once a year?"
The lady reporter (obviously embarrassed):
"Well, Sir, that's a new piece of information, but what's the relation between this phenomenon and Mad Cow disease?"
The Farmer
"And, Madam, do you know that we milk a cow twice a day?"
- "Sir, this is really valuable information, but what about getting to the point?"
The farmer:
"I am getting to the point, Madam. Just imagine, if I was playing with your tits twice a day and only screwing you once a year, wouldn't you get mad?"