Yes, that's an ox. Rampaging (as oxen are wont to do) through a hospital (as they're less wont to do).
It happened in Hospital Francisco Limongi on the outskirts of Rio de Janeiro, Brazil - and while the beast apparently knocked over a few doors, thankfully, nobody was hurt.
"A large number of ox roam Trajano de Moraes, a rural mountainous region of Rio," explains Nine News. "A lack of fencing and adequate security on the door was blamed for the unwelcome intrusion."