Tetanus In Horses


The microbe Clostridium tetani is responsible for causing the characteristic muscle rigidity often seen in tetanus, more commonly known as lockjaw. The organism is found in most soils and enters an animal’s body through dirty, neglected wounds andespecially via punctures. The exotoxin which C. tetani produces binds to the nerves at the site of the injury and then travels to
the spinal cord and brain. 

 

Signs:

A stiff gait, rigidity of the extremities ("sawhorse" stance), inability
to eat and overreaction to sounds are signs of tetanus. They
appear about two weeks to a month following infection, but
can be seen earlier depending upon the amount of toxin

The toxin prevents muscles from relaxing, so once a muscle
has been stimulated to contract, such as to close the jaw, it
cannot return to its original relaxed state, thus creating the
rigidity seen with the disease. Death results from either an
inability to breath or due to seizures.

Prevention:

Horses and humans are the species most susceptible to the toxin’s
effects. The best way to treat tetanus in horses is to prevent it. Tetanus
toxoid (vaccine) is given initially as two doses three to six
weeks apart followed by an annual booster. It provides strong,
long-lasting protection against the toxin itself, not C. tetani.
Tetanus antitoxin (serum) also works against the toxin, but is
only effective for two to three weeks. Antitoxin is best used
when the vaccination history of an injured animal is unknown, in
unvaccinated mares at foaling and for newborn foals born to
unvaccinated mares. The first tetanus toxoid injections should be
given at three to four months of age. Horses that are vaccinated
yearly should be given toxoid if they are injured or undergo
surgery more than six months since the last booster.

Treatments:

Treatment of tetanus is limited to providing muscle relaxation,
killing any bacteria still in the body using antibiotics
(penicillin), neutralizing the toxin with serum antitoxin, and
administering nutritional supplementation. Full recovery takes
weeks to months, but even with treatment up to 80% of cases in
horses are fatal.

 

 

 

 

The information contained within these articles is intended for educational purposes only, and not for diagnosing or medicinally prescribing in any way. Readers are cautioned to seek expert advice from a qualified health professional before pursuing any form of treatment on their animals. Opinions expressed herein are those of the authors and do not necessarily reflect those of the publisher or WHA.