In order to survive, R. equi requires iron from the foal’s body to replicate and survive. Researchers at Texas A&M University’s College of Veterinary Medicine recently examined the use of a semi-metal (gallium) that mimics iron as a means to disrupt R. equi‘s replication process. They concluded that gallium does interfere with R. equi‘s uptake of iron, which, in turn, inhibits the growth and development of the micro-organism, thereby decreasing the number of bacteria in the body. The information was presented at the 2006 AAEP Convention.

Ronald Martens, DVM, a professor at the university, said, “Iron is crucial for DNA synthesis of the bacteria. One of the body’s innate immune mechanisms is that iron-transporting proteins in plasma bind iron and store it within macrophages (specialized white blood cells that fight infection). This is to prevent its uptake by bacteria, and most bacteria cannot survive in the absence of iron. However, R. equi has the ability to obtain and use protein-bound iron. So, it circumvents this innate immune mechanism.

“Gallium seems to have great potential for the prevention and control of disease in foals caused by R. equi,” Martens said. “Short-term oral gallium therapy in newborn foals could provide protection against early infection with R. equi. This would provide additional time for maturation of requisite innate and adaptive immune functions and could substantially reduce the incidence of disease on R. equi-endemic farms. In addition, gallium used alone or in conjunction with standard antibiotic protocols may be valuable for the treatment of established R. equi infections.”

Get research and health news from the American Association of Equine Practitioners 2006 Convention in The Horse’s AAEP 2006 Wrap-Up sponsored by OCD Equine. Files are available as free PDF downloads