Vaccinations & Deworming


Routine vaccinations should be considered as a part of every horse’s health care regimen. Obviously, depending on your horse’s age and lifestyle, the vaccinations he or she needs will be quite different. At the KVC we are keen to develop a vaccination protocol ideally suited to each horse. Here are some basic guidelines to get you thinking before your appointment.

1) Foals

If a mare has been properly vaccinated prior to foaling, your foal should be protected by maternal immunity until the age of approximately 5 months. At this time, a vaccination protocol should be developed according to his or her needs. Tetanus and rabies are essential, and a tetanus booster must follow the initial inoculation 3-4 weeks later. Other considerations include West Nile virus, Eastern and Western encephalomyelitis, Influenza/rhinovirus, and Strangles.

2) Adult horses

Core vaccines include rabies and tetanus vaccinations yearly. Over the past few years, Eastern and Western Encephalomyelitis has been seen more frequently in Ontario, and at the KVC we have been using a Tetanus/EEE/WEE combination vaccine in most of our horses. A recent resurgence in the number of West Nile virus (WNV) cases in Ontario (including a horse in our practice!) also indicates this vaccine should be considered of higher importance.
Rhinopneumonitis/Influenza is a vaccine that should be given to horses traveling off-property to shows or events where they will be socializing with other horses of unknown vaccination status. A booster may be required if they were previously unvaccinated for this disease.
Strangles is a bacterial disease that seems to pop up sporadically in our practice area. It is acquired by contact with an infected horse and thus horses traveling off-property are at greater risk of contracting this disease. This vaccine is given intranasally and may require a booster if it has never been given previously.

3) Pregnant mares

Pregnant mares should be given their annual vaccines in a period of 4-8 weeks prior to their due date. This ensures maternal immunity will be passed on to their new foal and protect him or her for the first five months of life. Another vaccination that should be considered for pregnant mares is for Rhinopneumonitis (Pneumabort-K or Prodigy) – a vaccination that protects them from viral abortion. This vaccine is given at the 5th, 7th and 9th month of pregnancy.

Let us help you set up the right protocol for protecting your horse! If you have any further questions please call us anytime, or check out the AAEP website for further disease info: Vaccination Guidelines - AAEP


Deworming is another area we are trying to be actively involved in – as there has been a drastic rise in the amount of resistance to our current dewormers seen in the past few years. Historically, deworming has been performed (somewhat at random!) by horse owners, and the negative effects of this haphazard program have only recently become apparent.

Although we have done routine fecal sampling on pets for many years, it is a relatively new concept in the horse world. Many people have felt it is just as easy to give a dewormer as it is to bring in a poop sample – but with resistance to certain dewormers becoming more prevalent, we can’t be certain our treatments are working!

At the KVC, we have been working diligently toward implementing successful and sustainable deworming strategies for your farms. These strategies include manure management techniques, fecal egg counts and targeted deworming based on the results of the fecal egg counts. As with any new strategy, the first year will likely be the most labour-intensive, but the long term benefits will be to improve your horse’s health, minimize the amount of chemical dewormer going into your horse, and minimize the parasite contamination at your farm. Help us to fight the war on worms!!!