Abstract

Intravascular access in batoid species is commonly achieved using the ventral coccygeal or radial wing vessels. However, these approaches can be difficult due to the presence of cartilage, lack of specific landmarks, species variation, and small vessel size in many species. This study used postmortem contrast radiography and gross dissection to develop landmarks for a new, dependable vascular access to the mesopterygial vein in three Myliobatiform species commonly maintained in captivity: Atlantic stingray (Hypanus sabinus), cownose ray (Rhinoptera bonasus), and smooth butterfly ray (Gymnura micrura). The metapterygium cartilage sits adjacent to the coelomic cavity and supports the caudal half of the pectoral fin. The mesopterygial vein is located immediately ventrolateral to the metapterygium cartilage. Using the pectoral girdle and cranial third of the metapterygium cartilage as landmarks, vascular access can be achieved by directing a needle medially at a 45-degree angle toward the metapterygium cartilage. The species-specific shape of the metapterygium cartilage in adult cownose rays requires a less steep (∼30-degree) needle angle. The mesopterygial vein provides quick vascular access and is suitable for administration of large fluid volumes and intravascular drugs.

Acknowledgments

We appreciate the assistance of North Carolina Division of Marine Fisheries biologists Steve Poland and Jeffrey Dobbs for provision of the dissection specimens.

* Presenting author
+ Student presenter