Patzer

When the dog gang corners Bugs in the alley, there are nine dogs. When it reaches Bugs, there are only five.

When the bowler hat bulldog crashes into the manhole cover, "NYC" should have been reversed on his face.

When Bugs Bunny shows the dogs the book, the dogs were seeing the back of the book, which has no title on it.

Before meeting the gang of dogs, Bugs passes the same door (with the 'ice' note) and the box labeled 'ice' several times.