She paces in her cage, tripping over her two newborn cubs that she recently birthed as a result of artificial insemination. Each day thousands of people file by the beautiful, three-hundred-fifty-pound, Siberian Tiger. A piece of raw meat lays, untouched, near the small iron grate through which her keepers had recently thrust it. Elaborate scenery, including “play-things,” decorated the quarter-acre enclosure. Everything was state