April 2005

Should You Rely On Titers?

No. While overvaccinating can be problematic, not vaccinating can be fatal.

Your horse’s disease risk also increases somewhat based on how many horses he comes in contact with and the horse activity in the barn.

The wisdom of routinely giving our horses annual vaccinations is being questioned. In small animals, serious problems have been linked to overvaccination, including vaccine-induced fibrosarcoma in cats and autoimmune diseases.

As a result, more animal owners are requesting veterinarians check antibody titers before vaccinating. However, relying solely on titers as an indication of your horse’s degree of protection from disease has its own problems.

First, while titers measure the level of circulating antibody to a specific organism or toxin, antibodies are far from the entire picture. Before they even come into play, the horse uses a variety of nonspecific immune-system reactions that recognize invading or foreign substances and attack. …