Pectoral muscles (cat)

There are four pectoral muscles in a cat: pectoantibranchialis, pectoralis major, pectoralis minor, and xiphihumeralis.

Pectoantebrachialis

Pectoantebrachialis muscle is just one-half inch wide, and is the most superficial in the pectoral muscles. Origin, manubrium of the sternum, Insertion, in a flat tendon on the fascia of the proximal end of the ulna, Action, draws the arm towards the chest.

Pectoralis major

The pectoralis major, also called, pectoralis superficialis, is a broad triangular portion of the pectoralis muscle which is immediately below the pectoantebrachialis. It is actually smaller that the pectoralis minor muscle. Origin, sternum and median ventral raphe, Insertion, Humerus, Action, draws the arm towards the chest.

Pectoralis minor

The pectoralis minor muscle is larger than the Pectoralis major (1). However, most of its anterior border is covered by the pectoralis major. Origin, ribs 3-5, Insertion, coracoid process of scapula, Action, tipping of the scapula, elevation of ribs 3-5

Xiphihumeralis

The most posterior, flat, thin, and long strip of pectoral muscle is the Xiphihumeralis. It is a band of parallel fibers that is not found in humans, but in felines. Its Origin is the Xyphoid Process of the sternum, The insertion is the Humerous.