An insect repellent salesman, travelling through the countryside, came to a farmhouse and tried his pitch on the farmer.
"Sir," he said, "my bug spray works so well that I guarantee you will never be bitten again."
The farmer was skeptical, so he made the young man a proposition. "I'll tie you out in my cornfield buck naked, covered with that bug spray" said the farmer. "In the morning, if there isn't a single bite on you, I will buy a whole case from you."
The salesman was delighted. They went out to the cornfield and he striped. The farmer then sprayed him thoroughly with the bug spray and tied him to a stake.
The next morning, the farmer went back out to the cornfield and, sure enough, the salesman was there, hanging from his bonds, without a single bite on him. Not one bite, and yet he was a total wreck, looking pale, haggard and drawn.
The farmer was perplexed. "Son," he said, "you don't have one bite on you and yet you look like hell. What the devil happened?"
"For crying out loud, mister," the salesman gasped, "doesn't that calf have a mother?!?!"