Some men are seen shirtless, mostly in the boxing scenes.

Characters undress when going to bed, but nothing inappropriate.

A horse trips over, but turns out to be okay.

Champ hits his son in the face through bars. He gets mad at himself afterward, and begins punching a wall continuously, and we see his fist bleed.

Surprisingly, the only boxing scene is at the end. There is some blood.

None. Only euphemisms ("Oh, gee whiz!", etc.)

The Champ is an alcoholic.

A boy secretly steals some cigars to give to his father.

Smoking is a common thing in this movie, along with drinking.