The Collaborative International Dictionary of English v.0.48:

Hoof \Hoof\, v. i.
   1. To walk as cattle. [R.] --William Scott.
      [1913 Webster]

   2. To be on a tramp; to foot. [Slang, U.S.]
      [1913 Webster]

   To hoof it, to foot it.

   On the hoof, of cattle, standing (on the hoof); not
      slaughtered.

   beef on the hoof, live cattle.
      [Webster 1913 Suppl.]