Ancient Chinese Geldings

Here's an odd little bit of research:

Most of the horses in the terracotta army in a Chinese emperor's tomb had no testicles, pointing to the possibility of equine castration some 2000 years ago.

Yuan Jing, an archaeologist with the Chinese Academy of Social Sciences, studied the more than 600 terracotta horses within the tomb of Qinshihuang, the first emperor of the Qin Dynasty, who ruled from 221 BC to 207 BC.

He noted that all the 520 horses that pulled chariots had penises but no testicles.

However, some of the 116 cavalry horses were found to have testicles.