The Fox's name is revealed to be Reginald at the beginning of the film. However, he calls up "Reginald Fox" on the phone later.
While ten dogs are shown setting out at the beginning of the film, only four are ever shown together during the hunt, and only five come back at the end.
Ten dogs, including the female Cynthia, are shown during the roll call. However, 13 dogs are shown running through the gate, and Cynthia is not among them.
Reginald Fox gives Droopy a fake bone with a lit firecracker in it. The other dogs fight over it, and one of the them puts the bone in his mouth. When Droopy asks them which one took his bone, the bone in mouth of the stealing dog doesn't appear in the shape of a bone around his mouth until he shakes his head "no", and then the firecracker explodes.
The old man tells the hounds that "each one of you who brings a fox back to me will be rewarded with a steak." However, when Droopy reveals to the fox why they are all chasing him, the conditions have changed to "For each fox we bring back, we get a steak", meaning one dog could get multiple steaks.
When Reginald Fox is looking up a telephone number, the listings in the phone book are not in alphabetical order.