The Brookfield Zoo has lost its second animal in one week.The Chicago Zoological Society reports 'Dusti' the giraffe died in an accident. Before the zoo opened Saturday morning, one of Dusti's zookeepers found the animal caught in a rope and unresponsive. Officials say it looks like he reached over from his exhibit space to an adjacent hallway where the rope was located. Dusti arrived at Brookfield in 1998 from Busch Gardens in Florida. Last weekend, one of Brookfield zoo's dolphins died of a respiratory illness.