By Claude Canellas AUDENGE, France (Reuters) – French hospitals have long been using leeches to prevent blood clots after surgery and their use looks set to expand as scientists say the animal could in future be used to treat problems including rheumatism and osteoarthritis. For the last 23 years, Brigitte Latrille has been cultivating leeches in her laboratory near Bordeaux, and says she is doing a roaring trade. “In France, we’re getting orders from all the hospitals with plastic surgery centers, whether it’s Marseilles, Strasbourg or others such as the CHU hospital in Bordeaux,” she said.