At the Chengdu meeting of the annual Chinese Medical Exhibition, in the section for products used in traditional Chinese medicine, my host and I walked past a stand with a stack of cartons containing what looked like long tree roots. The emblem on the package was a buck deer. I asked him "Is that what I think it is?" He just smiled and said yes. Then he laughed when I said "Well, now I know why female deer run so fast".
Dried animal parts are a very big (and expensive) part of traditional Asian medicine, usually used to treating ailments in the equivalent areas of human patients. Deer gear is their version of Viagra. Mongolians must think along the same lines with horse hoses.