Most horse owners know about core vaccinations—meaning those that every horse should get against rabies, Eastern and Western equine encephalomyelitis, tetanus, and West Nile virus. But risk-based vaccinations depend on your horse’s level of susceptibility and exposure to the disease in question.

Risk-based vaccinations most often include those against influenza and rhinopneumonitis, but there are vaccines against equine viral arteritis, leptospirosis, Potomac horse fever, botulism and strangles, too. Among other things, the need for any of these vaccinations varies with your type of horse, where and how he’s stabled and whether he travels.

So, before you invest in risk-based vaccinations or put your horse through the vaccine protocol, ask your veterinarian to help you weigh the benefits versus the risks and costs.