Iowa Code § 163.46: Sale of semen.

The owner of a breeding bull located within this state shall not sell the semen from that bull for the purpose of artificial insemination unless the owner is in possession of a certificate of veterinary inspection signed and issued by a licensed veterinarian within six months before the date the semen is collected. The certificate shall not be valid if the bull is moved to other premises between the date of examination and the date of collection. The certificate shall show that on the date of issue the breeding bull had been tested negative for brucellosis and, to the best knowledge and belief of the examining veterinarian, was free from any infectious or contagious disease.