Ferghana horse, also called sweats blood horse in Chinese, is one of China's earliest major imports. It is native to Turkmenistan and during Han Dynasty (25AD-220AD), it was brought back to China by Zhang Qian's diplomatic mission. Since then, it became the bonded mount for Chinese ancient emperors. They loved it because it was well-figured and understanding. They even considered it as "horse from heaven".
As the horses sweat blood when they are running, they were given the Chinese name Han Xue Horse (literally means sweats blood horse). They can run fast for long hours and can even reach 4300 kilometers in only 43 days. Therefore, they are commonly used for long-distance rides and horse-jumping moves.
Source:
http://Traditions.cultural-china.com/en/211Traditions11893.html
