Desensitizing Your Horse to Fly Spray

A HORSE'S LAMENT: How do I hate thee? Let me count the ways. 'Tis the rankest compound of villainous smell that ever offended nostril. Yonder vessel full of foul sound and fury. Cruel icy tears assailing my body. --Equus Anonymous.

Some horses really hate fly spray, be it the smell, the sound the sprayer makes, the sensation of solution on skin, or some other evil element inherent in the heinous act of applying a spray-on fly repellent. It's a common problem.

Some goosey horses react simply because they've never been sprayed before. It's a novel experience and, thus, automatically a scary experience.

Other horses have a "procedure aversion." That is, they react adversely to anything that's "done" to them, including injections, medications (ophthalmic, inhalation, intranasal), blankets, leg wraps, hosing, clippers--they aren't prejudiced.

And there are the hard-core spray-a-phobiacs, the horses with a conditioned fear of spraying due to some specific negative incident in the past that either remains unaddressed or continues to be reinforced.

Fortunately, with appropriate desensitization and counter-conditioning techniques, one can usually achieve a fairly quick cure to spray aversion.

What Ails Thee?

In working through a horse's fears, it's helpful--but not necessary--to identify the cause of the fear. "A person can go through the whole desensitization process in a step-by-step manner and never really know what is bothering the horse, but still be able to achieve success," states Jeannine M. Berger, DrMedVet, a Diplomate of the American College of Veterinary Behavior. "However, if you know what is bothering your horse, you can specifically desensitize to that specific trigger and save time."

Berger, who deals with equine behaviors at the University of California, Davis, Equine Behavior Service, identifies some of the common causes that produce unwanted reactions:

  • Movement of person spraying up and down. "Horses are especially sensitive to movement into their visual field; fly spraying usually involves quick and jerky movements."
  • Sound of multiple bursts of spray.
  • Sensation of the watery solution being sprayed on. "Many horses don't like being hosed with water, either."
  • Smell.
  • The approach of the person with the spray bottle in hand.
  • Being tied and sprayed. "Some horses that are not fully halter broke cannot handle anything more than standing still. When the handler adds a spray, the horse pulls back."

Transformation Cometh

Desensitization, often coupled with counter-conditioning, is the favored means of changing a horse's response to specific triggers or stimuli.

"Desensitization is the process of reintroducing a horse to a fear-eliciting stimulus by using a gradient," says Berger. The goal is to replace an unwanted emotional reaction--fear, anxiety, aggressive arousal--with a more relaxed, comfortable reaction. Each step or gradient is done very gradually to avoid re-creating the fear response.

Counter-conditioning is the process of reinforcing a substitute emotional response: Instead of producing a negative response, the stimulus produces a positive response. "We recommend using counter-conditioning with desensitization if the horse shows a strong fear response," Berger states. "When desensitization and counter-conditioning are combined, the unwanted behavior is replaced with a positive behavior through a gradual process of reintroducing a low level of negative stimulus with a positive reward for a relaxed state."

Desensitization and counter-conditioning must be performed correctly to be effective, but fortunately, neither is difficult.

Preparation First, find a place to work with your horse that's safe, quiet, and free of distractions, advises Eric Davis, DVM, MS, Dipl. ACVIM, ACVS. "Make sure your voice and demeanor are calm: Horses recognize tension from body language, odors, etc.," says Davis, who is director of Rural Area Veterinary Services (a program of the Humane Society of the United States) and an associate veterinarian at Steinbeck Country Equine Clinic in Salinas, Calif.

Berger prefers having some sort of control over the horse, i.e., a halter and lead rope. Some experts, including Sophia Yin, DVM, Applied Animal Behaviorist, also feel you can work effectively if the horse is at liberty. Regardless, it's important to:

  • Proceed slowly;
  • Introduce just one step or gradient at a time;
  • Closely watch for signs that suggest fear (moving away, anxiety, or aggression) or acceptance (calm manner, disinterest, or interest in something else);
  • Make sure your horse is comfortable and accepting of the current step before proceeding to the next step;
  • Back off to an earlier, easier step if you get a negative response;
  • Never scold or hit the horse for a fear response;
  • Look for small, incremental improvements rather than instant results.

Desensitization Begin by holding the sprayer at a distance away from the horse where the horse isn't bothered by the sight of the sprayer. "How far away completely depends on the horse," says Yin, a former teacher in the Animal Science Department at UC Davis who is now in private practice at San Francisco Veterinary Specialists. It could be a foot or an arm's length away, partly behind your body, or held by a second person several feet away.

Next, bring the sprayer a little bit closer to the horse. Take care not to move it so close or so suddenly that the horse backs off or exhibits a fear response; the horse should stay with you the whole time. "When you've done that, perhaps, two to five times and the horse is okay with the object at that distance (he doesn't react to it), then move it closer," Yin says. "When you can get the spray bottle about a foot away, close to his head, try one quick half-second spritz in the air and see how he responds. If your horse accepts that, repeat a couple of times."

After your horse accepts air-spritzing, proceed to spraying another body part, such as his neck. Repeat a few times, eventually increasing the area until you succeed in spraying his entire body.

Take care around the face: Many otherwise stoic horses are sensitive there, and the mist can drift into eyes, ears, or nostrils, unless you block those areas with your hand. (Roll-ons make a good alternative for the head because you can better control their application.)

There are many variants on this process. Instead of using fly spray you can start using ordinary warm water. If the problem seems to be with the smell, apply diluted repellent either as a spray or on a sponge, again, just to a small area, then gradually work over larger areas. Think about what you're trying to accomplish and identify the steps you should take before starting each session, Berger suggests.

Desensitization plus counter-conditioning Using the above gradient technique, you offer very tasty food rewards at the same time. "The goal is the horse is always eating when he sees the spray bottle and that he's never reacting fearfully," Yin says. Sprayer equals reward; no sprayer, no reward.

Using small items that your horse can't grab and walk away with (a small handful of grain, small pellets, chopped carrots, etc.), feed your horse for about five to 10 seconds while presenting the sprayer. Your horse's muzzle should be in your hand and it should not move away when you present the sprayer. "As soon as the horse is finished," says Yin, "remove the object for two to five seconds, then repeat."

Important: The horse must want the reward. If his eating starts to slow or he loses interest in the food, end the session.

Another desensitization and counter-conditioning variation is to reward the horse for standing still when he sees the spray. "Present the spray," says Yin, "and if he just stands still, hurry up and reward him with a treat." You can use a clicker or a novel vocal tone (i.e., "YES!"), then hurry the food to the horse.

Warning signs In your desensitization and counter-conditioning process, what you don't do is just as important:

  • Avoid triggering unwanted behavior. "Every time the horse displays the unwanted behavior, the behavior is being practiced and reinforced," warns Berger.
  • Beware of reinforcing an unwanted behavior. "Horses learn quickly from negative or removal reinforcement," Berger states. "The owner sprays, the horse jumps, but the nature of the spray is that it stops after one squirt, which can negatively reinforce the jump."
  • Don't cease rewarding too soon. "Keep rewarding your horse until he's consistently good about spraying," suggests Yin.

A Moment's Passage

The time it takes to implement a change varies, although it's usually pretty short. "If you and the horse are strangers, and the horse is young and unsocialized, this may take a week," says Davis. "If the horse is used to you, with good ground manners, this might be done in a day or two."

Many horses can even be counter- conditioned in just five to 10 minutes, says Yin. "If you do it right, you can do it very quickly. It's the people who are impatient and want to skip steps who set their horses back. They could be fighting with their horses every day for months and months," and stress and fighting are the last things you want to associate with the application of fly spray.

About the Author

Marcia King

Marcia King is an award-winning freelance writer based in Ohio who specializes in equine, canine, and feline veterinary topics. She's schooled in hunt seat, dressage, and Western pleasure.

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