(CNN) -- A horse racing trainer who became engulfed in a doping scandal and was banned from the sport for eight years has appealed his sentence, the British Horseracing Authority (BHA) has confirmed.
Mahmood Al Zarooni, who worked at the world famous Godolphin stables in the English town of Newmarket, was banned from horse racing after admitting injecting his thoroughbreds with steroids.
The 37-year-old admitted a "catastrophic error" in administering prohibited anabolic steroids -- ethylestranol and stanozolol -- to 15 leading thoroughbreds.
All 15 horses, including the former 1,000 Guineas favorite Certify, were banned from racing for six months by the BHA.
The case rocked the sport and led to Godolphin principal Sheikh Mohammed bin Rashid Al Maktoum -- the ruler of Dubai -- shutting down the stables, saying he was "appalled and angered" by the doping revelations.
A statement on the BHA's official website read: "Mahmood Al Zarooni has lodged an appeal against the severity of his eight-year suspension from training.
"Al Zarooni, 37, was found guilty of administering anabolic steroids to 15 horses in his care at a BHA hearing on April 25.
"The former Godolphin handler, who was based at Moulton Paddocks in Newmarket, was officially charged with rule breaches related to prohibited substances, duty to keep medication records, and conduct prejudicial to racing.
"He will now contest the length of the eight-year ban, with the date for the appeal hearing to be confirmed in due course."
Al Zarooni waived his right to legal representation and accepted all the charges at a hearing in London at the end of April.
It led to Sheikh Mohammed locking down the paddocks and issuing a statement.
In it he said: "I can assure the racing public that no horse will run from that yard this season until I have been absolutely assured by my team that the entire yard is completely clean."
The 63-year-old Sheikh attended Newmarket racecourse on Saturday to see Godolphin colt Dawn Approach win the English 2000 Guineas.
According to AFP, Godolphin said Al Zarooni's appeal was nothing to do with them and was simply a matter between him and the BHA.
"He is no longer a Godolphin employee and the appeal is a matter between himself and the BHA. Godolphin has no involvement with this appeal," AFP quoted a Godolphin spokesperson as saying.
Soon after Al Zarooni's punishment was confirmed a second trainer in Newmarket revealed he was facing an inquiry on similar offenses.
The BHA confirmed Gerard Butler was being investigated after some of his horses tested positive for banned substances at his yard in February.
Butler told a British newspaper he was facing a ban after injecting his horses with a product used to treat joints but said he was so sure of its validity he entered it into his official medical records which were then sent to the BHA.
He called the incident "an unpardonable misjudgment" but said it hadn't crossed his mind there could be a problem with the medication.