Is it permissible to sell equine sperm, and if it is impermissible, does the buyer incur sin, and what is the evidence?

It is permissible to trade in the semen of a mare or other animals in two ways: The first is selling the semen after it has been extracted and stored. The second is renting a stallion to inseminate a female, and this is permissible according to some Companions, their Successors, and Malik, provided that the duration or the number of inseminations is specified, in order to prevent uncertainty (gharar).