Blakey, pictured above after being rescued from Spindles Farm. Blakey was rehabilitated by World Horse Welfare - his "after" shot is below.
Gray, 46, was stopped by police at a routine checkpoint in Kidderminster, Worcestershire, early today (NZ time).
He will appear in Aylesbury Crown Court, in Buckinghamshire, tomorrow.
Gray and other members of his family have been convicted over the ill-treatment of horses at Spindles Farm, in Amersham, Buckinghamshire, in January 2008.
It became the biggest equine rescue operation in British history, as authorities removed more than 114 horses from the property, three of whom had to be euthanized.
The bodies of 32 horses were found on the property.
The Grays challenged their convictions and sentences, but all were upheld barring two charges.
Gray, who was originally sentenced to 24 weeks in jail for the offending, was sentenced to 26 weeks in his absence, after he fled the court complex during a lunch break.
Gray has served only four days of his sentence, as he was released pending the outcome of his appeal.
Gray has been ordered to pay the SPCA £400,000.