The 2016 Olympic Games begin on Aug. 5 and end on Aug. 21. As of this writing at the end of July 2016, many of the horses are just arriving.
How do the horses fly on down to Rio? NBC’s Olympics website has the story.
Equitrekking lists in-flight amenities.
This article from the Rio2016 website shows a horse passport.
The Wall Street Journal has a video of the departure preparations for a couple of members of the Canadian team.