Hi Kate
Do you mean a greyhound? These are frequently wholly owned by individuals. These that don't make it are disposed of (in various ways) as they are so easy to replace. They are seen as commodities rather than living beings or pets and treated accordingly.
If you don't get any helpful replies please don't be surprised - there are so many retired grehounds going into rescue, and others that don't make the grade are sent wholesale to Spain where they are kept in appalling conditions, run off their legs then shot or hung !
If you are really interested in a racing greyhound this is not the place to come as the people here care about their dogs as pets and companions rather than commodities.
Not intending to preach, just explain
Christine