Regarding the compensation given to the owner of a stud animal when the transaction is not a lease.
Chapter on Selling the Musarrah (Animal with milk retained in udder)
Al-Mughni
Book of Sales
Primary text
If the owner of the stud animal accepts a gift or hospitality in return for its service, without it being stipulated as a lease payment, it is permissible. This is supported by the narration from Anas that the Prophet (peace be upon him) said, 'If it is an honor/hospitality, there is no harm in it.' This is permissible because it is based on an allowable means, thus accepting a gift for it is permitted, similar to compensation for cupping (hijama).
Supporting text
A narration from Ahmad via Ibn al-Qasim states that the owner should not accept anything. This is because what is prohibited regarding receiving payment is also prohibited regarding accepting a gift, analogous to the bride-price of a prostitute or the fee of a soothsayer. However, the ruling given concerning the cupper suggests a concession; the position that allows acceptance of the gift is considered more lenient for the people and aligns better with legal analogy, with Ahmad's statement interpreted as caution (*wara'*), not absolute prohibition (*tahrim*).