A rise in nocardioform placentitis cases in Central Kentucky’s 2011 foal crop caused concern among equine caretakers, veterinarians and the University of Kentucky Veterinary Diagnostic Laboratory (UKVDL). A placental infection that can cause late-term abortion or small, underdeveloped foals, the disease could take a toll on the Thoroughbred breeding industry.

The UKVDL reported via The Horse that in 2012, the number of confirmed cases dropped to a more-typical number, but that the 2016 crop had a small rise in cases in February before numbers dropped quickly later that year.

Though 2017 has just begun, the UKVDL has seen an increase in confirmed nocardioform placentitis cases, beginning with 10 abortions in December 2016 (compared to zero abortions in December 2015). Additionally, there were eight confirmed cases in the first two weeks of January 2017, with additional cases pending.

First identified in Central Kentucky in the mid-1980s, the development of nocardioform placentitis is not well understood. It can cause stillbirths, prematurity, late-gestation abortions, live but non-viable foals, and foals that are small and weak, but live. The lesions of nocardioform placentitis are distinctive and are gram-positive branching bacilli; they are found only on the placenta and do not reach the fetus.

It is not clearly understood how nocardioform placentitis is transmitted as the infection does not follow the transmission path of either ascending bacterial placentitis or septicemic bacterial placentitis. The cases tend to come in waves with some years having more cases than other. Scientists are investigating if environmental factors contribute to the disease. So far, nocardioform placentitis seems to occur after hot, dry weather.

Read more at The Horse.