Reproductive medicine in koi (Cyprinus carpio)

Each year more veterinarians are seeing ornamental fish patients and our knowledge of how to manage the pet fish patient is increasing at a rapid pace. A large percentage of these patients are nishikigoi (Cyprinus carpio) which are taxonomically an ornamental carp. In this country and in many parts of the world we refer to these fish as koi. Reproductive medicine problems are well documented in koi and a thorough knowledge of this subject will aid the fish practitioner in diagnosis and treatment.