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Horses will use their back and front legs in different ways to indicate how they are feeling. Horses can inflict serious injury with their legs, so understanding how your horse uses his legs to communicate will be very important for your personal safety. Your horse will paw or stamp the ground with his front legs when he is feeling impatient, frustrated, or uncomfortable. Splayed (spread out) front legs indicates that your horse is getting ready to run or bolt. It could also mean that your horse has medical issues that prevents him from standing properly; your veterinarian will be needed to diagnose the underlying cause. Lifting either one front leg or back leg signals a threat. If you see your horse doing this, step back to a safe distance; a horse kick can cause serious injury. Your horse may cock his back leg by resting the front edge of his hoof on the ground and lowering his hip. This indicates that he is relaxed. Your horse will sometimes engage in Bucking behavior, which is when he raises his back legs in the air. This is often playful behavior (sometimes accompanied by grunting and squealing), but can also indicate uncertainty and fear, especially if he's being ridden for the first time. Rearing up is another dual-sided behavior. It can signal playfulness in foals in the field but, if it is an angry stallion in fight mode, it can be a sign of fear when the horse cannot escape the situation. You can understand how your horse is feeling by looking at him as a whole to see how he moves and stands. For example, if your horse's back is raised, he could be sore from having the saddle on him for a long time. Rigid muscles and stiff movements can mean that your horse is nervous, stressed, or in pain. If you are not sure why your horse looks rigid or stiff, your veterinarian can conduct various behavioral and medical tests (dental exam, lameness exam) to determine the cause. Trembling is a sign of fear. Your horse may tremble to the point of wanting to run or fight. If he does this, give him plenty of space and time to calm down. He may also need to be desensitized to his fear; an experienced veterinary behaviorist can help your horse overcome his fear. Your horse may swing his hindquarters to indicate that he's getting ready to kick; move away quickly if he starts doing this. If your horse is female, she may swing her hindquarters to indicate that she is in heat and trying to get the attention of a male horse. Horses have a range of noises that they will make to communicate different things. Understanding what these different noises mean will help you better understand what your horse is trying to communicate with you and other horses. Your horse will neigh for several reasons. He may neigh to indicate anxiety or distress; this will be a very high-pitched sound and could be accompanied by a lowered tail and flickering ears. He may also neigh to acknowledge his presence. A confident neigh will sound like a bugle and will be accompanied by a slightly lifted tail, forward-pricked ears. A nicker is a soft, throaty sound. To make this sound, your horse will keep his mouth closed while producing the sound from his vocal chords. A mare will sometime use this sound with her foal. Your horse may also make this sound when he knows that it's almost feeding time. This is usually a friendly sound. Squeals can be a display of threat. Two horses who are meeting each other for the first time may squeal at each other. Squeals can also be a sign of playfulness, such as when your horse is bucking. Your horse will snort by inhaling quickly and then exhaling through his nose. With this sound, he could be signaling that he is alarmed when another animal has come too close to him. He could also be indicating that he's excited about something. Be aware that the act of snorting can get horses worked up; you may need to calm him down if this happens. Just like people, your horse will sigh to express relief and relaxation. The sighs are different for each each emotion: reliefdeep inhale, then a slow exhale through the nose or mouth; relaxationlowered head with an exhalation that makes a fluttering noise. Groans can indicate different things. For example, your horse may groan if he's in pain during riding (eg, landing hard after a jumping a fence, his rider thuds heavily in the saddle). He might also groan when he's happily exercising without pain. Groaning could also indicate more serious medical issues, such as constipation or gastric pain due to ulcers. If you have trouble determine why your horse is groaning, consult a horse expert.
Observe what your horse is doing with his legs. Look at your horse's overall posture. Listen to what noises your horse makes.