“Doc - How And Where Do I Give A ’Shot' To My Horse?”
© A.J. Neumann, D.V.M.
published in The Draft Horse Journal, Autumn 2006

I never thought I would ever write an article on this subject. Almost all of my clients here in Northwest Iowa have had a livestock background and in treating their horses I would leave them medicine which needed to be given by subcutaneous or intramuscular routes, and they would just do it as prescribed. Intravenous administration of drugs was always a different story as many of my clients could not perform this procedure. If it was not practical for me to visit the premises and give the IVs, I would have to teach them how and where to perform an intravenous administration of the prescribed medication.

Some of you readers may wonder why the sick animal is not brought into a clinic or why the veterinarian does not stop at the premises once or twice each day and treat the ailing horse. The answer is simply an economic issue. Most of my clients elect to treat their own horses, under my supervision, simply to save money. The cost of treatment has always been a factor in my practice, and, as a result, I have taught many of my clients how to give oral as well as injectable medications.

That is well and good for my clients but recently I have received, by phone and mail, a number of requests on where and how to give a horse a Shot whether it be for treatment or preventative vaccination of the animal. I find that many of these inquiries come from horse owners with little or no previous animal care backgrounds. Large horse stables will usually have veterinarians performing all of the health work or they will have trained personnel doing the job under veterinarian supervision. In short, these stables can afford these types of programs. So for those who have inquired, here is a short course in how and where to give a horse a Shot and why I do it this way.

There are three types of injections or shots, generally given to the horse. They are intramuscular, subcutaneous and intravenous. We abbreviate these by saying; IM, SubCu and IV. IM means that the shot or medication is delivered into the animal’s muscle. SubCu, in turn tells us the medicine or vaccine is placed just under the skin. IV, of course, means that the medication must be injected directly into the venous blood stream of the horse. Some vaccines and medications are shot up into the nose of the horse through their nostrils. The use of the intranasal route does not fall into the category of a shot as a needle is not used to gain entry through the horse’s skin.

The IM injection is the most commonly used in the horse. Many vaccines and medications are delivered to the horse by the IM route. The IM injection sites on the horse are the ones most open to discussion. Certain sites when used may cause considerable damage to surrounding tissue, as well as affecting the welfare of the animal, especially when infection or an abscess occurs at the site following the injection. For this reason I advise my clients and teach my students to never give an IM injection into the side of the neck, the brisket or the long hamstring muscle which runs down the rear of the hindquarter. Instead always give the IM injection into the large muscle mass on top of the rump of the adult horse or foal.

So why should we not use the neck, brisket and long rear muscle of the hind quarter of the horse? The muscle layers are very thin in these areas and should an abscess occur at these sites it will usually migrate down between the layers and eventually involve the shoulder, forelegs and lower chest as well as the abdominal area on the front of the horse, while those abscesses occurring in the hamstring muscle will often migrate down into the hock area.

If these abscesses occur the horse will be out of action for weeks on end and your wallet will suffer some pain as well. These abscesses are a mess when they occur.

The gluteal muscle on top of the horse’s rump is very thick and if an abscess should occur there, it will not migrate but can be opened and drained with very minimal damage to surrounding tissue. The beauty of this is the fact that these draft, driving horses and mules can be worked everyday, while those suffering from a neck abscess or swollen legs will not be able to work for a long period of time. The same goes for the saddle horse or pony.

Never ever give a nursing foal an IM injection into the neck area! If the neck muscles get sore from the medication the foal will stand with its head and neck straight forward and it cannot nurse. You will have to wean it and get it to drink out of a shallow pan.

Many veterinarians and horse handlers will not give an IM shot where it should be given into the gluteal muscle on top of the hips. Why not? There is an easy answer. They are scared to death they are going to get kicked! I have given thousands of these shots and have never been kicked once while doing it. If you have to deal with a fractious horse, use a twitch, or an ear hold, or raise the foreleg, or scratch his back, blindfold it, or tie up a rear leg, but give its IM shot in the top of the rump!

Better yet, you can train your horses or mules to receive a vaccination without a fuss. Start when they are young, if you can, and you will be able to vaccinate them with an IM shot out in the corral without catching them.

SubCu injections are made generally wherever the skin can be picked up by thumb and forefinger. The needle is then inserted through the skin to just below the fold of skin. On the draft or driving horse, this area should be directly behind the shoulder, on either side of the animal. Never inject the draft or any horse used in the harness in the area of the collar bed. Any injection in this area would render the animal useless for driving or draft purposes if the tissue became swollen, sore or abscessed. On the foal, the loose skin behind the shoulder is an excellent site for SubCu injections, which are often of considerable volume.

The IV route of injection is used quite often. It generally involves only two sites, which are the jugular veins, one of each being found on either side of the neck, down about in the lower third of the neck area. With a little practice one can soon learn to place his or her fingers over the venous area, press into the neck, and the vein will rise up and become visible in the area between your fingers and the jaw of the patient. Place the needle to be used onto the raised blood vessel with the point of the needle pointing toward the animals jaw. Slowly push the point of the needle through the skin into the vein.

Some operators will stab the needle into the vein. This procedure will often frighten the horse and it will rear and try to get away. One can make a horse needle shy by this stabbing method, which, by the way, is entirely uncalled for.

When administering medications IV one must be very careful and follow any and all directions plus making sure that the needle remains in the vein for the duration of the procedure.

In giving IM, SubCu and IV shots, always place the needle first and then attach the syringe. If blood comes from the needle in an IM or SubCu placement remove the needle and repeat the procedure.

Why do abscesses occur? It is impossible to completely sterilize an injection site on the horse. An attempt to do so would involve shaving the injection site and using a very good skin disinfectant on the area for at least a day. After all of the shaving, scrubbing and disinfection of the skin, it has been found that bacteria would still survive in the area.

We should all strive to have the injection site clean because we cannot sterilize it. Remove any loose hair and dirt from the area. Do not use water to wash the site if you are not shaving or clipping it. Instead use rubbing alcohol to clean the area. Soaking the skin and hair with soapy water seems to be the cause of abscesses forming, over the use of rubbing alcohol. I never clip or shave the hair coat from an injection site. All of my clients resent having these patches of skin showing on their animal’s neck and rump, so I just do not do it. I cannot remember when I have had an abscess form on an injection site of one of my equine patients. I repeat that you probably cannot be sterile in preparing the injection site, but you can be clean!

I believe most abscesses occur from the use of dull needles. Always use a new sterile disposable needle. The sharp point will penetrate the skin easily and cleanly without pushing a small amount of debris into the flesh such as happens with a dull needle.

Disposable needles can be purchased in many lengths and gauges. I generally use 18 gauge, 1 inch to 1 inch needles to IM, SubCu and IV horses. Generally the larger the number of the needle the smaller the lumen of the needle. A 14 gauge needle is much larger in diameter and lumen size than an 18 gauge needle. I use the 18 gauge needles almost exclusively on the horse for shots. The 16 gauge is somewhat larger in diameter than the 18 and the horse will usually react unfavorably to its use.

Another cause of an abscess is a large volume of medicine injected IM into one site. If a horse needs 40 cc of penicillin per dose I divide this into four Ð 10cc injections. I never inject more than 10cc into one site. I have found that injecting more than 10cc in one place increases the risk of an abscess and slows down the absorption of the drug.

If a horse, mule or pony is receiving IM shots on a daily basis, it becomes prudent to alternate the sites from the one side to the other, thus giving the animal's tissue a rest.

I would like to close with a short story for you about Jake The Mule and the needle. I bought Jake and other mules from the Chamberlin Mule Company at San Diego, California, in 1981. Jake weighed about 1,150 pounds, was a jack mule and blacker than the ace of spades. He had been born, raised, trained and worked on a Mexican ranch and sported a big Mexican figure brand on his left shoulder, which I couldn’t read. According to Mr. Chamberlin, Jake was a very good saddle mule. One could work cattle and rope off him as good as any ranch horse, but Jake had one problem; he had stomped a Mexican cowboy to death.

Seems as if they would mount Jake and then sock the spurs to him. He got tired of it so he would allow the rider to get a foot in the stirrup and then he would jump about two feet high and sideways about four feet. If you fell on the ground with a foot in the stirrup you were done.

To remedy Jake’s deal, the boys got to using a pair of pliers to pinch his ear so they could mount him. Jake got sick of it and one day he stomped a cowboy to death who was using his pliers in this fashion.

I was told of this history over and over and repeatedly warned not to twist his ears. I bought and used Jake as a pack mule. We tried riding him and found out what we had been told was true. I soon discovered that if you messed with Jake's ears he had more than a kindergarten education, as he was wonderfully accurate with any one of his four feet.

When I sold my mules, I kept Jake because I figured I would have to say do not twist his ears, and that would probably be the first thing his new owner would do. I did not want to hear that Jake had stomped another man to death so I never sold him. He died on the place.

I used Jake in my schools which I teach at my farm. At some point during each school, I would teach the class how and where to give a shot to a horse or mule. I always asked the students, when we got around to teaching the subject, which animal they wanted me to show them how to vaccinate.

Without fail, it was always, let’s see you give the mule a shot! I’d take my needle and syringe and walk right up to Jake, who stood there without a halter or lead rope on him, and gave him a shot exactly on top of the rump. He wouldn‘t move a muscle. The students were really let down. Just because he was a mule, they expected me to either make excuses and not vaccinate him or get hurt trying to do the job.

I had trained Jake and every one of my horses to take the needle. If I can do it - so can you!

So remember; in giving a mule or horse a shot, always use a new, sterile, disposable needle. They are readily available, inexpensive and come in many lengths and gauges. Use the smallest gauge to do the job. Never use a dull needle or a poor injection site because the end result could be quite costly to both you and your patient.

	1. Grasp the needle between thumb and forefinger. "Thump" the injection site with the heel of the hand a time or two; then drive the needle into the muscle. Attach the syringe to the needle and give the medication.
	2. Where the hand is placed marks the area on each side of the rump where IM "shots" should be given.
	3. One hand, with the syringe, is upon the animal's back scratching it; the other hand is placing the needle into the rump area. Scratching the horse's back often works as a distraction from the placement of the needle.
	4. If possible, never use the neck or collar area of the horse for an IM injection site. If an abscess or swelling should occur, as shown here, the animal will be on vacation for a long time, perhaps permanently.