A woman took a very limp duck into the vets' surgery. As she laid her pet gently onto the treatment table, the vet pulled out his stethoscope and listened to the duck's chest. After a moment or two the vet shook his head sadly and said "I'm sorry but your duck has passed away." The distressed owner cried "Are you sure?" "Yes, I'm sure, the duck is dead" he replied. "How can you be so sure" she protested "I mean, you haven't done any tests on him or anything. He might be in a coma or something."
The vet rolled his eyes, turned and left the room. He returned a few moments later with a black Labrador retriever. As the duck's owner looked on in amazement, the dog stood on its hind legs, put his front paws on the treatment table and sniffed the duck from top to bottom. The dog looked at the vet with big sad eyes, and shook his head. The vet patted the dog and took it out of the room.
He returned a few moments later with a cat, which jumped up onto the treatment table. The cat sniffed the duck from top to tail, sat back on its haunches, shook its head and meowed softly. The cat jumped down from the table and strolled out of the room. The vet looked at the women and said "I'm sorry but as I said this is most definitely, 100% certifiably, a dead duck."
He then turned to his PC and hitting a few keys, produced the woman's bill. "£150" she screamed "£150 to tell me my duck's dead?" The vet shrugged "I'm sorry, if you had taken my word for it the bill would have only been £20. But what with the lab report and the cat scan, it all adds up."