We purchased about 7 yearling heifers from sale barn ( big mistake) put them on small pasture for about 3 weeks and no problem .moved to a big pasture and they all got sick. yellow mucous in eyes,runing noses and blistered,scaling,loss of appitite. We have had no loss.checked temps on all cattle quanitined with 1 or 2 with 103.Gave la 200 for three days ,temp came down on the 2 head. I have a 2 year old brangus that was off by itself with no appitite and eyes and nose clear so we put her in a seperate pen and she has same symtoms as the sale barn heifers.have been treating with LA 200 for three days, temp is normal but she doesn't eat much. stool on this cow was black tar like and is now brown. Does this sound like IBR?