What Is A Tetanus Shot For Horses?

Last Updated on August 3, 2022

If you are a horse owner, you might be wondering which vaccinations your horse needs. Is a tetanus shot for horses necessary or just for high-risk animals? Let’s find out everything you need to know about tetanus in horses and whether a tetanus shot for horses is required.

What Is Tetanus In Horses?

Tetanus is a bacterial disease that can affect every horse. It is caused by a bacteria called Clostridium tetani that is able to survive in the soil and on surfaces for very long periods of time. Tetanus cannot be passed from horse to horse but is normally contracted when the horse sustains a puncture wound. The bacteria enter this wound and quickly multiply.

Although horses can contract tetanus from any type of wound, some injuries increase the likelihood. This includes puncture wounds, particularly of the hoof or muscle tissue. Also, high-risk injuries include surgical sites, lacerations, and exposed tissues.

Tetanus in horses causes severe changes to the central nervous system. The causative bacteria multiply rapidly and then die. When they die, they release a powerful nerve toxin which causes muscles of the body to spasm. This condition progresses rapidly, and only 20% of horses that contract tetanus will survive.

Treatment of tetanus in horses is most successful when symptoms are recognized early. The first sign you may notice is a change in the way that your horse moves or the way he stands. Progressive muscle stiffness will cause unusual signs such as the tail becoming stiff, the tail standing erect, and an unusual facial expression.

The muscle spasms in a horse with tetanus will progress quickly and soon cause problems such as difficulty breathing and swallowing. This condition was often known as lockjaw in the past, as the horses’ jaw would lock into spasms and they would not be able to eat or chew. Ultimately, the muscle spasms will lead to seizures and respiratory failure.

Check Out What Is A Check Ligament Injury In Horses?

What Is The Tetanus Shot For Horses?

Although tetanus in horses has a high mortality rate, luckily we have a very successful vaccination against this disease. Every horse should follow a vaccination schedule for tetanus, as they are all at risk of contracting this disease. Even horses that live alone will require a tetanus shot for horses.

The following vaccination schedule should be followed when giving a tetanus shot for horses:

  • Primary Vaccination For Foals

The primary vaccination course for tetanus in foals depends on whether the mother was vaccinated or not. Every fold should be given a primary three-dose series of tetanus vaccination. If the mother was vaccinated, this should be started when the foal is four to six months old.

If the dam was not vaccinated, the primary course should be started at three months of age. In this situation, it is common to also give the foal tetanus antitoxin to provide short-term immunity when it is born.

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Tetanus Shot For Horses
  • Primary Vaccination For Adult Horses

Adult horses that have not been vaccinated against tetanus before, or if their vaccination status is unknown, should be given two doses of tetanus vaccination with four to six weeks between each dose.

  • Booster Vaccinations

Once a foal or horse has had its primary vaccination course, it should receive regular booster vaccinations against tetanus. These booster vaccinations should be carried out on an annual basis.

If a horse sustains a wound or undergoes a surgical procedure more than six months after their booster, they should be given an additional booster. This applies even if the wound is relatively small, as even a tiny puncture wound can lead to tetanus.

Read more about Can A Horse Survive Aspiration Pneumonia?

  • Pregnant Mares

Pregnant mares should be vaccinated against tetanus to protect both themselves and to pass on immunity to their newborn foal via the colostrum. If the mare was not vaccinated previously, she should have a two dose primary course of tetanus vaccination at the start of her pregnancy. All pregnant mares should receive a booster tetanus vaccination 4 to 6 weeks prior to folding.

  • Tetanus Antitoxin

Tetanus antitoxin is used to give immediate but short term protection against tetanus. This is normally given in a high risk situation such as an unvaccinated horse that has sustained a wound. It can also be given to newborn foals when the dam has not been vaccinated.

Tetanus Antitoxin


So as we have learned, a tetanus shot for horses is vital to give protection against this disease. All horses should be vaccinated against tetanus, even those that live alone. They should then receive an annual booster vaccination, which can be brought forward in a high risk situation.

We would love to hear your thoughts on the tetanus shot for horses! Do you get confused by which shots your horse needs every year? Or maybe you’re worried that your pony needs too many vaccinations? Leave a comment below and we will get back to you!


How Much Tetanus Do You Give A Horse?

All horses should receive a primary course of tetanus vaccinations, which will normally involve three shots when they are a foal. Older horses that are not vaccinated can have a primary course of two vaccinations.

How Long Does Tetanus Shot Last In A Horse?

Once a horse has had its primary course of tetanus vaccinations, it will require an annual booster. This should be given every year, and may be administered earlier if the horse sustains a wound or injury.

What Are The Signs Of Tetanus In Horses?

Tetanus in horses causes severe neurological neurological damage. This leads to signs such as muscle stiffness, which may initially show as an unusual movement or stance. This quickly develops into a classic set of symptoms, including stiff ears, tail, jaw and facial muscles.

What Shots Does A Horse Need Yearly?

The shots that your horse needs yearly will depend on the location where you live. All horses should receive an annual tetanus vaccination. This is normally combined against other infectious diseases, such as West Nile virus virus and equine influenza.
The area where you live will affect the vaccinations your horse needs as some diseases are only endemic in certain areas. It is a good idea to discuss your horses vaccination protocol with your veterinarian.