Riding horse is slow and choppy

When riding horses since I installed 1.8, movement is extremely slow and choppy, making the horses virtually useless.

Issue experimented by both my husband and I, in both a server and in a Realm.

To reproduce:
1 - Find horse, feed it a bunch of wheat or sugar.
2 - Attempt to mount until tamed.
3 - Put a saddle on it.
4 - Move.
5 - Get angry, get off the horse, kill it and make leather armor.