Another new word has been added to the equine world–setae (prounced see-tay). Why? Horses have hair, caterpillars have setae. There are some researchers who hold the belief that these hair-like projections on the skin of Eastern tent caterpillars (ETC) might have something to do with all the health problems seen in horses in Kentucky and surrounding states in 2001 and 2002. What has become known as mare reproductive loss syndrome (MRLS) actually includes six distinct problems–early fetal loss, late fetal abortion, the birth of ill foals (with up to 50% mortality), pericarditis (fluid around the heart), unilateral endophthalmitis (infection in one eye), and encephalitis (inflammation in the brain) caused by the bacteria <I>Actinobacillus<I>