Boudreaux's dead duck

Boudreaux rushed into Doc Robicheaux’s office carrying a duck. He gently placed the duck on the exam table, it lay there limp and not moving.
“Doc, you gotta help my duck”, Boudreaux said.
Doc Robicheaux looked at the duck and shook his head. “Boudreaux, your duck is dead”, he said.
“Doc, you gotta do something - run some test - do something”, Boudreaux demanded.
“Okay”, Doc Robicheaux said.
The Doc whistled and a large black Labrador Retriever came in. The dog sniffed the duck from all sides, looked at the Doc, shook his head from side to side, and went back out.
The Doc made a clicking sound with his tongue and a gray cat came in. The cat jumped on the table and watched the unmoving duck for a couple of minutes, turned to the Doc, shook his head from sided to side, and went back out.
“Boudreaux, your duck is dead”, Doc Robicheaux told Boudreaux, “Dat’ll be 125 dollars”.
“Dat’s a lot just to tell me dat my duck’s dead”, Boudreaux protested.
“Boudreaux, I examined the duck and told you it was dead - that woulda been 10 dollars. You’re da one dat demanded da Lab-Work and da Cat-Scan”, Doc Robicheaux explained.