ureteral orifice in dogs

The slit-like opening of either ureter into the bladder; normally, the two ureteral orifices are placed at the posterolateral angles of the urinary bladder trigone while the internal urethral orifice is placed at its anteroinferior angle (apex); wide gaping usually indicates vesicoureteral reflux. Every claim on this page comes from the Leumas anatomy graph and carries its source.

What the ureteral orifice is

The slit-like opening of either ureter into the bladder; normally, the two ureteral orifices are placed at the posterolateral angles of the urinary bladder trigone while the internal urethral orifice is placed at its anteroinferior angle (apex); wide gaping usually indicates vesicoureteral reflux. The atlas records it as a organ at the organ scale in the dog.

Where the ureteral orifice is

It sits in the trunk, within the urinary system. Not positioned individually. Drawn inside the structure this dataset says contains it — the containment is asserted, the exact spot within it is not.

What the ureteral orifice connects to

The atlas records 5 typed relationships for it, across 3 kinds of connection. part of fundus of urinary bladder and ureterovesical junction.

Supply and innervation

This dataset asserts no arterial supply, venous drainage or innervation for the ureteral orifice. 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 Mercier's bar, orifice of ureter, orificium ureteris, ostium ureteris, ureteral meatus and ureteral opening, and 3 more. Searching any of those names reaches this page.

Source

Uberon multi-species anatomy ontology (Mungall et al.), CC BY 4.0. Term UBERON:0012303, version 2026-06-19, retrieved 2026-08-24. Licence: CC-BY-4.0.

• Part of: fundus of urinary bladder and ureterovesical junction.
• A kind of: anatomical structure and urethral opening.
• contributes to morphology of: ureterovesical junction.

Questions

Where is the ureteral orifice?

It sits in the trunk, within the urinary system. Not positioned individually. Drawn inside the structure this dataset says contains it — the containment is asserted, the exact spot within it is not.

What does the ureteral orifice connect to?

Part of: fundus of urinary bladder and ureterovesical junction.

Is the ureteral orifice 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.