There can be nothing worse when you have placed a bet on a horse race that having just seen your horse finish in first position the claxon then sounds at the racecourse which indicates the stewards are going to hold an Enquiry into the race!
The reason why the stewards will want to review that race is that something will have happened during the running of that race that caught their attention, and as such there could be a risk that the horse that you just backed which won the race could be disqualified from that race if it has fallen foul of one of the many rules of racing, such as it had interfered with the running of another horse or the jockey did something not permitted by the rules.
If a horse does get disqualified from a race it has just won or is disqualified from one of the winning positions in that race such as coming second or third then everyone who has bet on that horse will lose their bets.
However, many betting sites and bookmakers now offer a special compensation type of rule which is known as a first past the post rule and as such if a horse you have placed a bet on for any reason what so ever is disqualified and you have placed a bet that would have been a winning one on that horse then you will still be paid out even though your horse has been disqualified from its position in the race.
As a horse race bettor you are strongly advised to always stick to placing your bets and wagers at those betting sites offering this first past the post rule as it will save you from losing out if your horse is ever disqualified!