Equine Health Update Issue 2 Volume 19 - Page 28

EQUINE | Equine Disease Update in December 2016 with a local veterinarian indicating he was seeing an increase in cases. UKVDL pathologists and epidemiologists noticed an increase in cases submitted to the lab in January 2017 and alerted local practitioners and farm managers through listserv and social media. Typically, nocardioform cases are first noted as early as October and run through May of any given year. The ma- jority of cases are diagnosed from December through April, usually peaking in mid-March (Figure 2). Through the third week of February 2017, UKVDL has confirmed 44 cases of nocardioform placentitis. Of these 44 cases, 31 have resulted in abortion, 12 in viable foals, and in one case a live but non-viable foal. The means of transmission is not yet identified. Nocar- dioform lesions are not similar to those of other types of bacterial placentitis or septicemic bacterial placentitis. Environmental factors are being investigated thorough- ly and early analysis indicates an increase in nocardio- form placentitis cases after a summer of hot, dry weath- er. Nocardioform placentitis cases are almost always lower in years associated with a high incidence of lep- tospiral abortions, which is correlated with weather that is wetter than normal. Analysis of farms affected with nocardioform placentitis indicates larger farms with more pregnant mares and higher stocking densities are at greater risk. Preliminary data indicate that mares that spend more time in the barn are at risk of developing the disease; increased grazing times appear protective. There is a statistical indication that pre-breeding treat- ments with NSAIDs or progesterone could be protective, but this needs further study. Mares that are given post- breeding human chorionic gonadotropin (hCG) are at significantly lower risk, but this also requires further study. Based on cases of nocardioform placentitis received by UKVDL from January 1, 2010, through February 21, 2017, there is little evidence that the disease recurs in particular mares. One exception is a mare that had a pla- centa submitted in 2011 that was positive for nocardio- form and a fetus submitted in 2016 that also was diag- nosed with the disease. The likelihood of recurrence of the disease in previously affected mares would appear extremely low. Contact: Jackie Smith, PhD, MSc, Dipl AVES jsmit8@uky. edu (859) 257-7559 University of Kentucky Veterinary Diagnostic Laboratory Lexington, KY Equine Cardiac Disease Equine cardiac disease is an uncommon but potentially serious condition. Clinical signs range from poor per- formance to sudden death. Causes of cardiac disease in horses include congenital malformation, chronic valvu- lar degeneration, cardiomyopathy, inflammatory or in- fectious disease, ruptured chordae tendineae, and car- diotoxins. This article describes common cardiotoxins that have been implicated in affecting horses in Central Kentucky. Ionophores (e.g. monensin and lasalocid) are common feed additives and supplements intended for cattle, pigs, or chickens. Exposure occurs when horses have ac- cess to concentrated mineral premixes containing iono- 28 • Equine Health Update •