What horse species is dying out?

One horse species that is dying out is the Shire horse, with its characteristically powerful legs and hooves fringed with silky white hair, has become a symbol of Britain's heritage. The horses are dying from old age and there aren't enough colts, and filly's being born. Only 150 were born last year. One hope is breeders have been selling this type of horses all over the world to the highest bidder. This species of horses may live on.