Rio Ferdinand has been found guilty of improper conduct and fined £45,000 by the Football Association for comments on Twitter.The defender denied he was being racist after responding to a tweet describing Chelsea's Ashley Cole as a "choc ice".But an independent commission ruled the Manchester United centre-half had brought the game into disrepute."The commission found that the breach included a reference to ethnic origin, colour or race," read an FA statement.Ferdinand was also warned as to his future conduct. Manchester United have decided against appealing the decision.The term relates to the black and white nature of a choc ice and can imply someone is being black on the outside and white on the inside.The tweet appeared on Ferdinand's timeline after Chelsea and England left-back Cole appeared in court as a defence witness for team-mate John Terry , who was cleared of racially abusing Ferdinand's younger brother, Anton, in a game against QPR on 23 October last year.Terry has since been charged with improper conduct by the FA for the alleged comments he made to Anton Ferdinand, a charge he has vowed to contest.Terry, 31, is alleged to have used "abusive and/or insulting words and/or behaviour" during the game.