At the scene with the cow, when Charlie finally "kills" the beast, and lays on his back, a hand is visible from behind the cow's neck for a few seconds before being pulled back behind the cow.
THAT'S CHARLIE'S HAND! If you watched this scene so well, then you would know that Charlie had his hands around the cows neck strangling him, and when he THOUGHT he killed him ('cause he's alive at the end of the movie,) he laid down on the ground, and one hand was still behind the cow's neck!