Related to Neat's-foot: Neatsfoot oil
an oil obtained by boiling the feet of neat cattle. It is used to render leather soft and pliable.

See also: Neat

References in periodicals archive ?
The new boots would then have been filled with neat's-foot oil and hung up in the roof of the shed to season.
Neat's-foot oil, shaving cream, water, mallets and good-old American spit also work, but you could let it happen naturally.
Right now the leather is a bit stiff but I'm sure with regular use and sparing applications of neat's-foot oil it will become more comfortable.