I have a 18 month old bull that has been losing weight and looking poorly for the last month. I gave him a dose of Ivomec in Oct. He has always been the one on the bottom of the food chain (rooted out of the feed trough until all others had thier fill). Two weeks ago, I moved him off by himself. While doing the feeding tonight, he was having a bowel movement and the consistency was not normal. The droppings came out in clumps more like horse droppings. Any ideas of what maybe going on? Should I be concerned? Thank you.