It is well documented that endotoxin-mediated disease is the #1 cause of death in horses, with mortality exceeding 50%. In the neonate, Salmonella sp. and E. coli are common causes of endotoxemias secondary to failure of passive transfer. The mortality rate may exceed that of the adult. To make a comparison, the mortality associated with Streptococcus equi, rhinopneumonitis and influenza combined is estimated at only 2-3%.