There probably aren't many equestrians out there who haven't been bitten or kicked at by a horse. It's widely accepted as a risk that we take when working with these animals. But what if I told you that a majority of those (painful) instances could be prevented with just some simple knowledge and observation?
Although it may seem like a horse comes out of nowhere with teeth or hooves flying, they actually give off subtle warning signs before they do lash out physically. This comes from patterns of behavior within horse herds: horses naturally try to preserve energy (and avoid drawing the attention of predators) by keeping the peace. So when they want to assert dominance in order to claim some food, or a water source, or a companion for example, they first use body language to indicate their intention ("get out of my way, or I'll beat you up!"). If those warning signs are ignored or challenged, they will then escalate the behavior to include nipping or kick threats. These, if still ignored, can escalate into a full-blown walloping, by equine standards.
This behavior is consistent, whether it's aimed at another horse or at a human. But other horses are pretty good at spotting the threats before they become action, whereas many humans haven't learned to spot the threats as easily and end up getting walloped before they even see the warning signs.
So what are these behavioral signs? Pinned ears is one that most people learn about pretty early on in their experience with horses. When a horse's ears are lying flat on their head, that's a definite sign to pay attention and stop whatever you're doing with the horse before the behavior escalates. But there are also other subtler signs:
Stamping a hoof: can just be due to irritation from flies - but if there aren't a lot of flies around and the stamping started around the same time that you started doing something (brushing a certain spot, putting on tack, etc.), you may want to back off and reevaluate your approach.
Wrinkled nostrils: A clear sign of annoyance. Some horses display this behavior more than others.
Holding the head higher than normal: If the head goes up, so should your alertness. A horse going into possible fight or flight mode will tense up and lift its head higher than normal (versus a relaxed state) as preparation for its next action.
Rapid swishing of the tail: If the horse seems to be swishing its tail more than the usual swishing of flies, then it's a clear sign that the horse does not like whatever is going on.
Tense eyes: The opposite of what we call "soft eye". The horse's face appears tense and the look in their eye is "hard".
Make it a part of your everyday practice to observe your horse as you're feeding, training and grooming them - and especially take time to observe them with other horses. If you become proficient in reading their body language, you can help prevent the next horse-related injury from happening in the first place.