blood island in dogs

Blood islands are structures in the developing embryo which lead to many different parts of the circulatory system. They primarily derive from plexuses formed from angioblasts. Within them, vacuoles appear through liquefaction of the central part of the syncytium into plasma. The lumen of the blood vessels thus formed is probably intracellular. The flattened cells at the periphery form the endothelium. The nucleated red blood corpuscles develop either from small masses of the original angioblast left attached to the inner wall of the lumen or directly from the flat endothelial cells. In either case the syncytial mass thus formed projects from and is attached to the wall of the vessel. Such a mass is known as a blood island and hemoglobin gradually accumulates within it. Later the cells on the surface round up, giving the mass a mulberry-like appearance. Then the red blood cells break loose and are carried away in the plasma. Such free blood cells continue to divide. Blood islands have been seen in the area vasculosa in the omphalomesenteric vein and arteries, and in the dorsal aorta[WP, unvetted]. Every claim on this page comes from the Leumas anatomy graph and carries its source.

What the blood island is

Blood islands are structures in the developing embryo which lead to many different parts of the circulatory system. They primarily derive from plexuses formed from angioblasts. Within them, vacuoles appear through liquefaction of the central part of the syncytium into plasma. The lumen of the blood vessels thus formed is probably intracellular. The flattened cells at the periphery form the endothelium. The nucleated red blood corpuscles develop either from small masses of the original angioblast left attached to the inner wall of the lumen or directly from the flat endothelial cells. In either case the syncytial mass thus formed projects from and is attached to the wall of the vessel. Such a mass is known as a blood island and hemoglobin gradually accumulates within it. Later the cells on the surface round up, giving the mass a mulberry-like appearance. Then the red blood cells break loose and are carried away in the plasma. Such free blood cells continue to divide. Blood islands have been seen in the area vasculosa in the omphalomesenteric vein and arteries, and in the dorsal aorta[WP, unvetted]. The atlas records it as a region at the region scale in the dog.

Where the blood island is

This dataset records no region or system for it. No positional evidence of any kind. Drawn outside the body so it can still be found and counted, never inside it.

What the blood island connects to

The atlas records 5 typed relationships for it, across 5 kinds of connection. part of embryo.

Supply and innervation

This dataset asserts no arterial supply, venous drainage or innervation for the blood island. Only a minority of structures carry those edges here, so an empty answer means nothing has been recorded — not that there is nothing to record.

Also called

Also recorded as ventral lateral plate mesoderm, blood islands, VBI, caudal hematopoietic tissue, posterior ICM and posterior blood island, and 1 more. Searching any of those names reaches this page.

Source

Uberon multi-species anatomy ontology (Mungall et al.), CC BY 4.0. Term UBERON:0003061, version 2026-06-19, retrieved 2026-08-24. Licence: CC-BY-4.0.

Questions

Where is the blood island?

This dataset records no region or system for it. No positional evidence of any kind. Drawn outside the body so it can still be found and counted, never inside it.

What does the blood island connect to?

Part of: embryo.

Is the blood island the same in other species?

This page describes the dog. The human record of the same structure sits beside it on /compare, over one shared model rather than two atlases built separately.