MONTREAL, Jan 16 (Reuters) - The Cirque Du Soleil, known for its high wire, fantastical shows worldwide, brought its employees down to earth on Wednesday with the announcement it was laying off 400 people, or 8 percent of its workforce. One of Canada's best known exports, the Cirque said it was struggling with rising costs of its productions as well as the strong Canadian dollar, which has risen to par or higher against the U.S. dollar over the past few years.