Lord Carnarvon, the Queen’s racing manager, has died of a heart attack at the age of 77.

A prominent owner-breeder himself, Lord Carnarvon became the Queen’s racing manager in 1969 and oversaw the royal string during a period which included the top class classic-winning fillies Highclere and Dunfermline.

Lord Carnarvon saw his own colours carried to success by Tamerlane in the 1950s and more recently by those fast fillies Lyric Fantasy, winner of the 1992 Nunthorpe Stakes at York, and Niche.

During the early 1990s Niche won the Lowther Stakes at York and the Nell Gwyn Stakes and Falmouth Stakes, both run at Newmarket. Carnarvon, who also bred the Breeders’ Cup Sprint winner Sheikh Albadou, had horses in training with Richard Hannon, Sir Michael Stoute, Roger Charlton and Paul Webber.

Hannon, who was responsible for Lyric Fantasy and Niche, said at Doncaster races: “We had some great times together and I was totally shocked when I heard the news. He was in such good shape and kept himself in such good condition. We got on very well and he loved coming to the stable to see his horses.”

Hannon added: “There have been two occasions when I have felt like giving up training, when Niche died and when I heard this news.”