This section is from the book "The Horse - Its Treatment In Health And Disease", by J. Wortley Axe. Also available from Amazon: The Horse. Its Treatment In Health And Disease.
A small, thin, triangular muscle arising from the transverse processes of the lumbar vertebrae.
Insertion. - Into the posterior border of the last rib.
Action. - To assist in expiration.
By some this muscle is considered to be part of the internal oblique muscle of the abdomen.
 
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