HOW DO I GET MY 4 YEAR OLD TO STOP NIPPING/BITING?

First you have to identify when your horse is nipping. Is he doing it when you tack him up, when you are feeding him, when you are holding him and conversing? (all the time?)

Basically what you have here is a lack of respect.

Regardless of when, you must stop this nasty habit.

NEVER EVER SMACK OR STRIKE YOUR HORSE WHEN HE NIPS YOU.
YOU DO NOT CORRECT YOUR HORSE IN THIS MANNER; YOU JUST CULTIVATE A HEAD SHY HORSE.

The best defense to a nipping horse is to teach the horse to respect your personal space. My horses know when I put my hand up in a STOP gesture to turn their heads away from me. They turn their heads away from their feed boxes before they get fed. I had a wonderful trainer teach me the importance of a horse’s respect for my “personal hula hoop.”

Here is an excellent article about a nipping Off the Track Thoroughbred.

http://sweetironfarm.com/wordpress/?page_id=60
There is a TON of information out on the web for correcting this behavior. Ones that are similar to the article attached here are practices savvy owners should follow. Stay away from the ones that advocate hitting

AND FOR PETE’S SAKE….DON’T LET YOUR BABY HORSES MOUTH ALL OVER YOU! By allowing this you create a nipping monster!