Round Belly

One of my Koi is getting very, very round in her belly. I think she is unable to pass her eggs. She is isolating herself from the rest of the group and appears to be having trouble swimming as she is so large. She is eating normally - is there something I can do? Many thanks, Michel

Your Koi might be egg-impacted. Normally, if Koi if Koi don't expel their eggs, they re-absorb them. If something goes wrong and they don't, the eggs will then turn into a tumor. The only way to remove the tumor is to have a veterinarian perform surgery.