Lucknow: What killed the black bucks in Kanpur zoo is still to be known. In order to ascertain the cause of the death of five black bucks in Kanpur zoo in the first week of September, the viscera of the dead animals and samples of food and water that was given to them, was sent for examination to the Centre for Wildlife, Indian Veterinary Research Institute (IVRI) Bareilly. UP Forest Department has set up a three-member committee to probe into the incident. A senior official from the department said,