The number of migrants allowed to work in the British racing industry is being cut, following intervention from the Home Office.

The changes, which mostly affect Sheikh Mohammed’s Godolphin operation in Newmarket, were applied after immigration minister Mark Harper MP queried recruitment for jobs that UK or EEA nationals could have filled.

Home Office figures show Godolphin recruited 2,425 non-European Economic Area migrants between 2010 and 2012 under special legislation allowing people in elite sport to work in the UK for up to 12 months.

Godolphin ranked 13th of UK companies using this “tier five” visa scheme, which also includes Formula 1 teams.

In May, Mr Harper asked the British Horseracing Authority (BHA) to review criteria for applicable jobs. Roles removed with effect from July included racing secretaries, gallops men and security staff.

Godolphin recruited 635 migrants in 2012, 540 in 2011 and 355 in 2010.

The BHA said figures include double and triple counting of some workers who return annually.

A BHA spokesman told H&H: “Increased employment figures are also directly relative to Godolphin’s employment of a second trainer and therefore the large increase of horses-in-training, which necessitates more staff.”

Separate concerns have been expressed that other specialist roles at Godolphin, not served by this scheme, may have been filled by foreigners qualified and registered in their home countries but not in Britain.

The Royal College of Veterinary Surgeons recently checked names of vets known to have spent time in Newmarket without holding the MRCVS qualification.

Following the seizure of unlicensed drugs from Sheikh Mohammed’s premises, last month his wife Princess Haya issued directives to staff.

These included a requirement that all staff are “fully licensed under the jurisdiction in which they are operating. Particular reference needs to be made to veterinarians and farriers.”

Princess Haya’s spokesman said: “I would not draw any inferences about the past from the directive.”