A farmer had a herd of cows and the bull wasn't doing his job of servicing the cows. So the farmer calls in the vet, the vet runs some tests on the bull and says to the farmer " I could put him on a course of injections, Or we could try this old cowman's trick" The vet walks over to the nearest cow, lifts her tail, rubs his hand across the cows crotch and then rubs his hand under the bulls nose. The bull gets an instant erection, climbs on the cow and starts servicing her. The farmer is amazed. That night he is laying in bed next to his wife and he thinks " I wonder is it works on humans?" He carefully rubs his hand across his wife's crotch and then rubs his hand under his nose. He get an instant erection, he wakes his wife up and says " what do you think of this?" His wife looks at him and say " You have woken me up at this time of the morning, just to show me that you have a nose bleed."