When Gray Beaver says to White Fang "Learn that or you'll learn the feel of this.", he throws a stick onto the ground and it lands in front of White Fang. In the next shot, the stick is gone.
When Weedon Scott lays White Fang down on Collie's bed, White Fang is wrapped in a blanket. When the shot cuts back to White Fang after Collie says "Whoa! What are you doing? Not in *my* bed!", the blanket is gone.
When Weedon Scott lays White Fang down on Collie's bed, White Fang is pointed toward Collie. When the camera cuts back after Collie says "Whoa! What are you doing? Not in *my* bed!", White Fang is now facing Weedon.
When Collie says "Looks to me like you were in some kind of a fight.", she is sitting in front of White Fang. The shot cuts to White Fang responding. In the shot after that, Collie is gone.
Before White Fang goes for the steak, Weedon Scott opens the door for White Fang to leave. Seven shots later, when Collie says "Now I know where the phrase 'wolfing down your food' came from.", the door is closed.
At most points of the movie, characters do not leave foot- or paw-prints behind.
After White Fang scares Lip-Lip away by growling, a shot shows four dogs pulling a sled, but the dogs do not leave paw prints and the sled leaves no tracks.
Repeated footage: when young White Fang is examining the teepees, before his encounter with Lip-Lip.
After White Fang runs away from the Native American camp, he finds the cave where he was born. After he gets scared by bats flying out, he goes in. Two shots later, in a shot from behind White Fang, he starts to say "Maybe this wasn't such a good idea after all.". In the next shot, when he finishes talking, his mouth does not move.
In the close-up shot of Lip-Lip's eyes, you can see a corner of his mouth. When he says "Let's see what kind of a runner you are," to White Fang, his mouth is clearly not moving.
When Collie asks White Fang "Will we see you again?", he replies "I don't know. Maybe. Someday." White Fang's mouth clearly does not move when he says "Someday."