* Horse's age: Foals typically receive their first tetanus vaccination at 4-6 months old, followed by booster shots every 4-6 weeks until they are at least 6 months old. After that, they receive booster shots annually.
* Horse's vaccination history: If a horse has a complete vaccination history, they may only need booster shots every 1-2 years.
* Horse's risk factors: Horses that are exposed to wounds, rusty objects, or manure are at higher risk of tetanus and may need booster shots more frequently.
* Local recommendations: Always consult with your veterinarian to determine the best vaccination schedule for your horse, as they will consider your specific circumstances and local recommendations.
Generally, a horse should receive a tetanus booster shot every 1-2 years. However, it's crucial to follow your veterinarian's advice for your horse's specific needs.
Remember, tetanus is a serious and potentially fatal disease, so vaccination is vital to protect your horse.