Having a good vaccination program for your horse or horses should not be overlooked. Vaccinations protect them from a variety of dangerous illnesses and are worth the money you may have to spend on them.
If you have a herd of horses, the beginning of a good vaccination program will start with maintaining good herd immunity by giving the horses a proper diet and avoiding unnecessary stresses. You should also isolate new horses for about two to four weeks before introducing them to the rest of the herd. Try to avoid spreading anything to your herd from the new horse after contact with it.
There are three different types of vaccines: killed vaccines, modified live vaccines, and subunit vaccines. Killed vaccines introduce the dead disease to the horse's body, modified live vaccines are live but not very harmful to your horse (it is just another way of introducing the disease to the body), and subunit vaccines usually don't contain the whole disease organism and are given through the nose.
Depending on where you live, your vet may recommend different vaccinations, but these are generally the ones to keep in mind:
Encephalitis (Eastern, Western, and Venezuelan)
Equine viral arteritis
For a good vaccination program, keep in mind the diseases in your area, the number of horses in your herd, what the horses are used for, how much they travel and where they travel to, and the frequency of contact with other horses. Vaccinating your horse or horses can save both you and the horse a lot of pain, trouble, and money.