I have seen horses falling down many times in war movies while running. How do they make horses fall down in war movies? Are they highly trained to know fall down at some place or some barriers are given to them?
Nowadays horses are trained to fall safely. almost all animal performances are under the close supervision of the Film and TV unit of the American Humane Association. Stunt horses can be trained to fall on command safely. Some techniques used to ensure the horses safety :
Sadly in the older films they actually do the inhumane things & use trip wires to make the animals fall and there were cases when the animals were killed such as in a 1940 Jesse James movie where 8 horses were killed. ref : http://horsefame.tripod.com/stunts.htm