#beast_of_burden__jument  an animal such as a donkey or ox or elephant used for transporting loads or doing other heavy work
  supertype:  work_animal  an animal trained for and used for heavy labor
  subtype:  pack_animal__sumpter  an animal such as a mule or burro or horse used to carry loads
     subtype:  packhorse  a workhorse used as a pack animal

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