Vaccination for young horses

All horses should be vaccinated against at least tetanus (NZPH Library)

Q: Can you please tell me a general vaccination plan for a young horse? My mare is due shortly with her first foal – she herself has been regularly vaccinated against tetanus. Will I need to get a strangles vaccine done too?

Gemma, Manawatu

Vet Dave Van Zwanenberg replies:

Vaccination of the mare with tetanus toxoid four weeks before she is due to foal is advisable to ensure good levels of tetanus antibodies in the colostrum. Some clients also prefer to inject the foal as soon as it is born with a tetanus anti-toxin. Tetanus anti-toxin is not a vaccination, but a serum that binds to the actual tetanus toxin and prevents its action. This protection is short-lived and lasts for only a few weeks. Vaccination at this age would be useless as foals are unable to mount an immune response to vaccines until around three months of age.

At three to four months of age the foal should be vaccinated with tetanus toxoid vaccine. A booster vaccination is then given a month after this and a second booster a year later. Repeat booster vaccinations should then be given every two to five years. Although the data sheet has a label claim of five years, my personal preference when attending a wounded horse which has not had a booster in the last couple of years is a repeat vaccination.

All horses should be vaccinated against tetanus – there are no exceptions.The disease is best prevented through vaccination and the vaccine is highly effective. Once tetanus has been contracted it is very unrewarding to treat and ultimately fatal, though many animals can be nursed for relatively long periods of time before succumbing.

There is the option for vaccination against strangles, herpes and salmonella. Vaccination against these diseases is dependent on your own situation. For mares and foals in high risk situations – such as at stud where a large number of animals are mixed together or where there is a previous history of the disease – vaccination is definitely beneficial.

Mares in foal are often vaccinated at five, seven and nine months of pregnancy against herpes to reduce the risk of abortion, and this often forms part of the stallion contract for a live foal guarantee.

For the majority of horses, vaccination against these diseases is usually not necessary as they are at a very low risk of encountering these pathogens. If you are unsure, then discuss your personal situation with your local equine vet.