She drove out of the city and into the country where there were many sheep farms. She spotted a sheep farmer, stopped her car and said, "If I can tell you exactly how many sheep are in your field, will you give me a sheep?" He said "Sure!" She counted and said "131." The farmer said, "That's Right! Go ahead and get a sheep." The blonde went and got her sheep. 

Then, the farmer said, "If I tell you what color your hair really is, can I have it back?" and she said, "Yes." 

"Blonde. Now give me back my dog."