Revealing mistake: When Sylvester is on the run from Porky, he dives under the bed, but the cels of him diving were placed over the bed, so that he appears to dive on top of the bed and disappear.
Audio problem: When the drunken cat hides inside the goldfish bowl, we cut to the two fish inside the bowl and you can hear the sound of the bowl rolling on the table, but it does not roll.
Continuity mistake: The front door to Porky's house is coloured white, but when the door is opened in some shots, it changes to yellow.
Continuity mistake: When Porky throws the cats out of his house at the start of the cartoon, the footprints in the snow change position between shots.
Continuity mistake: When Porky is thrown out of the house by the kitten, you can see there are two footprints in the doorstep and there is a note in one of the milk bottles. But when we return to the kitten, the footprints and note have disappeared.
Continuity mistake: When the kitten says "cheese" when Sylvester is talking to the other cats after fleeing Porky's house, Sylvester slaps him and you can see there are footprints in the snow. But after a quick cut to Sylvester saying "listen!" we return to the cats and the footprints have disappeared.
Continuity mistake: Porky's nightcap disappears when he discovers the Men from Mars on the pillow in his bed.
Continuity mistake: When Porky is thrown out with the other cats, you can see there are three cats beside him, but when we see Porky in the next shot, the cats are nowhere to be seen.
Continuity mistake: When the cats are fleeing after hearing "Lassie", you can see that the front door has molding on it. But when the kitten lowers the doorknob to jump through the keyhole, the door is plain. In the next shot, when the drunk cat dives for where the doorknob was and hits the door, the molding is back, and when he falls to the floor in the next shot, the door is plain again.
Continuity mistake: When Porky is thrown out of the house, the cat next to him has yellow eyes, but in the next shot they are white.
Continuity mistake: When we see the cats lounging around, the bottle the drunken cat is holding has nothing on the label, but in the next shot it now reads "Arsenic and Old Grapes."
