Tiny bacteria and viruses can cause serious health problems for horses. These microscopic malefactors also present challenges for researchers who study them in hopes of discovering better prevention and treatment methods. The researchers, however, don’t give in. They spend their careers carefully studying microbes that impact our horses. And when it’s time to move on and enjoy a well-deserved retirement, it’s gratifying to look back and see what’s been accomplished.

John Timoney, MVB, MRCVS, DSc, PhD, Keeneland Chair of Equine Infectious Diseases at the University of Kentucky’s (UK) Gluck Equine Research Center, reviewed what scientists have learned about streptococcal infections—important in the horse industry for a variety of reasons—along with some questions that remain unanswered, during a mini-symposium held in honor of his retirement. He delivered his lecture Oct. 7 at The Club at UK's Spindletop Hall, in Lexington.

Timoney described his research in detail for attendees. Following are a few important findings for horse owners to understand.

Streptococcus Basics

There are two key Streptococcus species in horses: S. equi and S. zooepidemicus. S. equi is a clonal descendant of an ancestral strain of S. zooepidemicus—essentially, it was formed based on an ancient S. zooepidemicus strain. Despite their similar names and origins, decades of observation and research have shown that these organisms behave very differently, Timoney said