A horse who flinches in response to being sprayed from a bottle isn’t being unreasonable—it’s a prey animal’s natural reaction to a sudden hissing sound. Most horses quickly realize there isn’t anything to fear, but some remain wary, making the application of fly repellents a frustrating dance down the barn aisle. If you start a desensitization program now, however, he can overcome this aversion by the time insects are in full force this summer. All you’ll need is a spray bottle, water and a lot of patience.
Start by filling a spray bottle with plain water and standing several feet away from your horse. He can be in a medium-sized paddock or held loosely by an experienced friend, but do not tie or confine him. Feeling trapped will only make him more anxious.
Begin by spraying the air. If your horse does anything more than simply looking in your direction, step a few feet away and try again. You want to find the distance from which you can spray without causing him to become worried or tense. When you find that distance, spray until the bottle is empty. Avoid praising the horse or giving treats when he’s tense or you may inadvertently reinforce unwanted behavior.
The next day, do the same exer- cise but start spraying a bit closer. If the horse reacts, back up a bit and try again. Then spray until the bottle is empty. Do the same the next day. With each repetition, you will most likely be able to get closer to the horse with less reaction, until eventually you can stand next to him and apply the spray. The keys to success are consistency---so do this daily---and being willing step back when the horse seems wary.
If you must apply fly spray to a fearful horse without delay, soak a towel in the mixture and wipe it directly on his coat. You will get the same benefits without the confrontation.