The ostrich is the world's largest living bird, and it's massive size renders them unable to fly. Adult males stand 2.4 m tall and can weigh well over 100 kg; the hen is slightly smaller. They have a long neck, long bare legs and two toes. Their strong legs allow them to run up to 70 km per hour when necessary, with strides of up to 8 m. Neck and thigh muscles are well developed and unfeathered.br/br/The first commercial ostrich farm was established in South Africa in about 1860 and today the feathers and skins are harvested, with the ostrich industry being a fast growing agricultural business.