Lee Pearson will be hoping to add to his gold medal tally

GB won seven individual gold medals at the last world championships in 2003 and are the current European, World and Paralympic team champions.

Included are Athens team gold medallists Debbie Criddle, Lee Pearson, Nicola Tustain and Anne Dunham.

The event at Hartpury College takes place from 20-22 July.

Selectors have named 10 riders who will compete as individuals for GB. In addition, four of the riders will compete in the team event. The team must include at least one grade 1a or 1b rider.

They have also named five riders, who will be aiming for good performances to help them qualify for next year's Beijing Paralympics but will not be eligible to win medals in Gloucestershire.

Great Britain will face stiff opposition from Germany and the Netherlands, who won silver and bronze in Athens.

However, both Nicola Tustain and Lee Pearson will not be partnered by their top horses at the event.

Tustain's mount Prinz Heinrich, with whom she has won team and individual golds, suffered an injury in March and she is riding her veteran dressage horse Hotstuff, who also helped Sophie Christiansen win individual bronze in Athens.

Pearson's multi-gold winning Blue Circle Boy is also ruled out and he will trial alternative horses for the next two weeks.

"It is unfortunate to have lost two very experienced horses, but other combinations have shown great improvement and new partnerships have proved themselves worthy of taking on the best in the world," said performance manager David Hunter.

"There's no room for complacency but I'm confident that the strength and depth of the British squad will give us a good chance of successfully defending our title."

The 15 selected riders will take part in the Hickstead Premier League from 28 June-1 July with the riders who will be competing in the team event at the World Championships to be named afterwards.

World Championship squad:
Grade 1a: Sophie Christiansen (Berkshire), Anne Dunham (Wiltshire)
Grade 1b: Ricky Balshaw (Shropshire), Lee Pearson (Staffordshire)
Grade II: Felicity Coulthard (Lancashire), Nicola Tustain (Denbighshire)
Grade III: Debbie Criddle (Somerset), Simon Laurens (Channel Isles)
Grade IV: Michelle Crunkhorn (Nottinghamshire), Denise Shawns (West Lothian)