Young horses are more susceptible to the dangers of tetanus than their older counterparts and are at a greater risk of death due to the disease, according to recent study carried out by Belgian researchers at the University of Liege.

Their research also revealed that, contrary to a common belief, the administration of tetanus anti-serum (TAT) is not 100% effective in preventing tetanus, said Gaby van Galen, DVM, MSc, primary author of the study, which was published recently in a Dutch veterinary health review.

Tetanus is caused by an anaerobic bacteria found in the soil and in feces. It infects horses through wounds. Clinical signs include spasms, stiffness, anxiety, perspiration, extended neck and head, prolapse of the third eyelid, retracted lips, and an elevated tail. Horses that have difficulty breathing or can no longer stand are significantly more likely to die from the disease, the study reported.

Comparing case studies of 30 horses and a donkey admitted to the university’s clinic between 1991 and 2006, van Galen’s team found that 84% of the animals were 5 or less than 5 years old and that 77% of these died or were euthanized within eight days of diagnosis, compared to 20% of those older than 5. The total survival rate of all equids in the study was 32%. Whereas the average age of survivors was 6.7 years old, that of the non-survivors was less than half that age, at 3.2 years. None of the equids had been properly vaccinated, according to the study, although some of them had received TAT preventively (before castration, for example).

“All horses are at risk for tetanus,” van Galen said. “But sadly, more and more people truly believe that there is no good reason for vaccinating against tetanus besides putting money in veterinarian’s pocket. Horse owners need to understand that it only takes a very small wound, often invisible to us, to develop tetanus. Also, they should never subject