External intercostal muscle 6

Musculus intercostalis externus VI

Draws each rib forward and outward on the one in front, enlarging the chest in inspiration.

System
Muscle
Region
Thorax
Sides
Paired: left and right
External intercostal muscle 6 (Musculus intercostalis externus VI) of the horse, left side: a three-quarter view of the muscle.

Where it runs from and to

A muscle is told apart from its neighbours by what it takes hold of at each end, which is also what decides what it does when it shortens.

Origin
The caudal border of a rib.
Insertion
The cranial border of the rib behind it, the fibres running caudoventrally.
Action
Draws each rib forward and outward on the one in front, enlarging the chest in inspiration.
Nerve
The intercostal nerves (ventral branches of the thoracic nerves).

Written for Vetomica in its own words from the standard reference anatomy of the horse; the books it was checked against are listed below.

Terminology

English
External intercostal muscle 6
Latin (NAV)
Musculus intercostalis externus VI
Status
A valid term in the Nomina Anatomica Veterinaria
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