Tetanus in Horses Vet Guide 2025 – Dr Duncan Houston 🐴🦠

By Dr Duncan Houston, BVSc – definitive veterinary insight on tetanus (“lockjaw”) in horses: from pathophysiology to prevention and recovery.

Introduction

Tetanus, caused by Clostridium tetani, leads to severe muscle stiffness, lockjaw, and often fatal spasms in horses. It earns the nickname “lockjaw” due to jaw rigidity. While uncommon, mortality reaches up to 75–80% in non‑vaccinated horses—even with treatment :contentReference[oaicite:3]{index=3}. This guide explains how tetanus develops, its warning signs, diagnostics, treatment protocol, prevention strategies, and prognosis for recovery.

🧬 How Tetanus Develops

Tetanus spores are widespread in soil, manure, and decaying matter. Contamination through wounds—especially deep punctures, sole abscesses, or surgical sites—creates an oxygen-poor environment that allows spores to germinate and release tetanospasmin. This neurotoxin travels via nerves to block inhibitory neurotransmitters, leading to uncontrolled muscle contractions :contentReference[oaicite:4]{index=4}.

🔍 Incubation & Risk Factors

• Incubation period: 3–28 days (often ~9–10 days) :contentReference[oaicite:5]{index=5}.
• High-risk wounds: foot punctures, lacerations, umbilical/injection sites, castration or parturition wounds :contentReference[oaicite:6]{index=6}.
• Foals: especially vulnerable via umbilical infection if mare lacks immunity :contentReference[oaicite:7]{index=7}.

⚠️ Clinical Signs to Watch

Recognizing early symptoms is essential:

• 🦴 Lockjaw—difficulty opening mouth, chewing/swallowing challenges :contentReference[oaicite:8]{index=8}.
• 🐴 Sawhorse stance—legs stiff, tail erect, neck extended :contentReference[oaicite:9]{index=9}.
• 👁️ Protrusion of third eyelid, erect ears, anxious facial expression :contentReference[oaicite:10]{index=10}.
• 😓 Muscle rigidity, spasms triggered by noise or touch, sweating, fever, increased respiration and heart rate :contentReference[oaicite:11]{index=11}.
• ⚰️ In severe cases, recumbency, breathing paralysis, and death occur within 7 days of onset :contentReference[oaicite:12]{index=12}.

🩺 Diagnosis

No definitive lab test exists—diagnosis is based on clinical signs and wound history :contentReference[oaicite:13]{index=13}. Veterinarians must rule out other neurologic conditions (e.g., rabies, lead poisoning). Wound culture is rarely conclusive.

🔬 Treatment Protocol

Tetanus treatment is intensive and requires early intervention:

• Antitoxin/Immunoglobulin: Neutralizes circulating toxin—administer immediately :contentReference[oaicite:14]{index=14}.
• Antibiotics: Broad-spectrum agents such as penicillin or metronidazole to eliminate the bacteria and prevent further toxin production :contentReference[oaicite:15]{index=15}.
• Muscle control: Sedatives or muscle relaxants (e.g., diazepam, acepromazine) to reduce spasms :contentReference[oaicite:16]{index=16}.
• Wound care: Clean and debride all wounds thoroughly to remove spore sources.
• Supportive Environment: Quiet, dark stall, deep bedding, and minimal handling reduce stimulus-triggered spasms :contentReference[oaicite:17]{index=17}.
• Nutritional and respiratory support: Provide soft feeds at chest height; in severe cases, assistance breathing or sling support may be necessary :contentReference[oaicite:18]{index=18}.

⏳ Prognosis & Recovery

Morbidity is high—but outcomes improve if the horse remains standing during treatment (fair prognosis) versus recumbent (poor) :contentReference[oaicite:19]{index=19}. Full recovery typically takes 2–6 weeks; surviving horses require months of rehabilitation :contentReference[oaicite:20]{index=20}. Mortality remains high (up to 80%) in severe or untreated cases :contentReference[oaicite:21]{index=21}.

🛡️ Prevention Strategies

• Vaccination (Tetanus toxoid): Core vaccine for all horses. Foals start at ~3 months, with annual boosters; broodmares receive boosters near foaling :contentReference[oaicite:22]{index=22}.
• Wound booster: Any significant wound >6 months post-vaccination should trigger a booster :contentReference[oaicite:23]{index=23}.
• Hygiene: Keep paddocks and surgical areas clean; promptly disinfect wounds.
• Foal care: Pregnant mares should be vaccinated so colostrum supplies neonatal immunity. Foals in high-risk environments may need antitoxin early :contentReference[oaicite:24]{index=24}.

📋 Prevention Checklist

📌 Role of Horse Owners

• Stay calendar-aware—mark vaccination and wound booster dates.
• Ensure prompt wound care and veterinary evaluation.
• Monitor for early signs—immediate veterinary action can save lives.
• Support stable environment and nutrition during treatment.

📲 Ask A Vet Support & Conclusion

Tetanus in horses is severe but largely preventable with vaccination and proper wound management. Early recognition and intensive support significantly improve survival. Always treat suspected cases as emergencies.

Need personalized shot reminders, wound-care protocols, or emergency planning tools? Ask A Vet equips you with tailored schedules, symptom monitoring, and tele-vet access via our app. Download the Ask A Vet App today and keep your horse protected against tetanus. 🐎🛡️