4.  Educate your horse about loading and shipping.
Loading is the most stressful part of the entire shipping experience and the time when injuries are most likely to happen.  Make sure your horse is thoroughly familiar and comfortable with the whole procedure.  If you horse is a particularly difficult loader, it's wise to get the help of an experienced and patient trainer to  help rebuild his confidence.  And, even if you never go anywhere, load your horse several times a year and drive around the neighborhood as a refresher.

5.  Maintain good air quality inside the trailer.
Unless you are shipping in the coldest, wettest climates in an open stock trailer, the risk of horses getting too cold is minimal compared to the risks associated with stagnant air, accumulating exhaust fumes and excessive heat.  When in doubt about the temperature, blanket the horses and leave open air vents or windows.  To check for drafts, ride in the back of an empty trailer, and adjust vents and windows to redirect any strong blasts that could chill the horses.  Keeping rear window closed, using floor mats without bedding and wetting hay are measures that reduce amount of dust in the trailer.

6.  Rest horses at least a week after a long journey.
Shipping-induced physical changes that leave a horse vulnerable to illness can persist for days after the trip is over.  To ensure you don't stress an already compromised horse, plan for the horse to arrive at this destination a week before he'll be asked for a major athletic effort.