http://www.chinafeedonline.com/cfo/news/show_news_detail_p.jsp?id=100220和http://www.baidu.com/s?wd=%D1%F8%CD%C3%D2%B5&lm=0&si=&rn=10&ie=gb2312&ct=0&cl=3&f=1&rsp=0看一下