Abstract
Reproductive success of common stingray species under human care has surpassed the need for managed breeding programs. Therefore, animals are housed in single-gender groups. Female populations are easier to manage due to lower conspecific aggression. However, these populations are at higher risk for reproductive disease like endometritis, oophoritis, cystic hyperplasia of the reproductive tract, secondary infections (coelomitis, pyometra), and eventual death.1,2,3,4 Surgical ovariectomy may be one option for prevention of reproductive complications. Ovariectomy has been accomplished in female southern stingrays (Hypanus americanus) but is only successful in a specific size range (ovaries small enough and coelomic cavity large enough).3,5 The purpose of this study was to assess the feasibility of a laparoscopic technique for ovariectomy in cadaver stingrays that could be performed rapidly and safely on stingrays of various sizes. Using 4 Atlantic stingray cadavers, Hypanus sabinus, ranging in size from 22 to 30 cm disc width, we tested several approaches and established a technique using triangulation of 3.5 mm ports. These were made in ventral recumbency on the dorsum just left of midline to target the active left ovary. Stay sutures were placed at the most caudal aspect of the coelomic cavity and a stab incision was made through the skin. A 3.5 mm threaded cannula was inserted and secured with a purse string suture. The coelomic cavity was insufflated with CO2, and a 3.2 mm, 30° scope was used to visualize placement of the other two ports in a similar fashion. The ovary and epigonal organ were visualized, the ovary was elevated, and the LigaSure was used to detach it from the epigonal organ. With the development of this technique, future studies will investigate applicability to live animals. This may enable improved management of stingray populations maintained under human care.
Acknowledgements
The authors wish to thank Dr. Jill Hendon of the University of Southern Mississippi’s Gulf Coast Research Laboratory and Dr. Robert George of Ripley’s Aquariums.
* Presenting author
+ Student presenter
Literature Cited
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