Continuity mistake: When Porky puts Sylvester in the basket in the kitchen, an arrow lands on the wall. But after Porky leaves, we cut to Sylvester and the arrow has disappeared.
Continuity mistake: When Porky thanks Sylvester for saving him, Porky is wearing a nightcap on his head. When the mouse in the cuckoo clock knocks Sylvester unconscious with a mallet, we cut to Porky and the nightcap has disappeared.
Continuity mistake: When Porky sends Sylvester down the stairs to stay in the kitchen, Sylvester crashes into an umbrella stand and there are several umbrellas in the stand. But when we see Porky at the bottom of the stairs a little later on, the stand is now completely empty.
Continuity mistake: When Sylvester grabs the tree to fight the mice in the house, the sky in the background is red. But when he runs back to the house, the sky is now dark.
Continuity mistake: When Porky puts Sylvester in the basket in the kitchen, he walks to the door and you can see the door has a handle on it. In the next shot, the handle has disappeared.
Continuity mistake: When Sylvester's conscience appears by the tree stump, the position of Sylvester's left leg on the stump changes between shots.