Study Answers Key Questions About Nocardioform Placentitis, But Etiology Remains Elusive Sponsored by: A new study published in the peer-reviewed journal Theriogenology reveals more about nocardioform placentitis, a placental infection that has plagued breeders and stud farm managers for decades. Placentitis is believed to account for 19 percent of equine infectious abortions nationwide, but much remains unknown about the disease. A research team led by Dr. Carleigh Fedorka at the Gluck Equine Research Center in Lexington, Ky., studied 264 mares — 145 who were suspected to have the disease and 119 with apparently healthy pregnancies — and compared characteristics of their pregnancies and resulting foals. The study found that nocardioform placentitis tends to be associated with older mares, and it isn't contagious between mares in the same turnout group. One episode of nocardioform placentitis does not necessarily presuppose another in the same horse the following year, and mares did not seem to experience abnormal cycles or reduced fertility after a case of nocardioform placentitis. Mares who were given antibiotics and hormones throughout their pregnancies to stave off the disease were no less likely to develop a case of nocardioform placentitis than those who were not.