 Shire stallions may be black , bay or grey . They may not be roan or have large amounts of white markings . Mares and geldings may be black , bay , grey or roan . In the UK stallions may not be chestnut , but the colour is allowed by the US registry . Stallions must stand at least 17 hands ( 68 inches , 173 cm ) high when mature , and they average around 17 @.@ 2 hands ( 70 inches , 178 cm ) . Geldings stand at least 16 @.@ 2 hands ( 66 inches , 168 cm ) high and mares at least 16 hands ( 64 inches , 163 cm ) . Their average weight ranges from 900 to 1 @,@ 100 kg ( 2 @,@ 000 to 2 @,@ 400 lb ) The head of a Shire is long and lean , with large eyes , set on a neck that is slightly arched and long in proportion to the body . The shoulder is deep and wide , the chest wide , the back muscular and short and the hindquarters long and wide . Not too much feathering is to occur on the legs , and the hair is fine , straight , and silky . Smaller Shires , under 17 hands ( 68 inches , 173 cm ) , are generally preferred for working horses , while taller horses , especially those over 18 @.@ 2 hands ( 74 inches , 188 cm ) , are used for show and promotional purposes . The breed is known for its easy @-@ going temperament . Shires have been identified to be at risk for chronic progressive lymphedema , a chronic progressive disease that includes symptoms of progressive swelling , hyperkeratosis , and fibrosis of distal limbs . The disease is similar to chronic lymphedema in humans . 
