Abstract

Egg stasis, the inability to complete ovulation and expel eggs, is a poorly characterized syndrome in fish. We used a modified ovariohysterectomy to remove large egg masses from three Irish Lords, with 1 to 3 years accumulation of eggs.

Anesthesia was induced with 100 mg/L tricaine methanesulfonate and maintained at 50 mg/L in sea water. Fish were positioned in dorsal recumbency; the ventral midline was disinfected with iodophor solution, covered with a sterile transparent drape and the skin and body wall incised from the pectoral fin arch to anterior to the vent. Exteriorization of bulky egg masses was blocked by the colon ventral to the connection between lateral lobes. Rochester-Carmalt forceps were clamped across one oviduct at a time. The ovarian blood vessels were ligated, and the oviduct was transfixed and ligated with 3–0 PDS. Forceps were drawn under the colon, the procedure was repeated on the other side, and the egg masses were excised and removed. The abdomen was flushed and filled with saline. The body wall and skin were closed separately with 3–0 PDS using a simple continuous pattern. Coelomic air was removed by coelomocentesis and the fish were recovered.

The Irish Lord with only 1 year of eggs began eating within a week, was returned to its display tank 4 months later, and continues to do well. The fish with multi-year eggs never resumed eating and died after 1 and 4 weeks. We recommend performing surgery once egg stasis is recognized, before multi-year accumulation develops.