Hrvoje Brzica: Comparatve gross morphology of larynx
of the dog (Canis familiaris) and bottlenose dolphin (Tursiops
truncatus). Original
scientific student paper.
Faculty of
Abstract
With
this study 1 compared anatomy of the larynx of dog (Cams familiaris) and
bottlenose dolphin (Tursiops truncatus). Two specimens conserved in 4%
water diluted formalin of dog larynx and three specimens of bottlenose dolphin
larynx were used which were bisected in great detail. 1 determined that larynx
of bottlenose dolphin is positioned more rostraly than that of a dog, and it
has specially developed arytenoepiglottideal tube which is positioned close to
the caudoventral part of the vomer. Arches of cricoid cartilage are not
ventraly fused, laminae of the thyroid cartilage are
strenghned with tendinous fibres and are much wider in order to serve as
attachment to much stronger laryngeal muscels than those of a dog. Arytenoid
cartilages are small and attached to cuneiform or corniculate cartilages which
are elongated and positioned dorsaly to epiglottic cartilage forming arytenoepiglottideal
tube. Epiglottic cartilage is latero-lateraly flattened and keel-shaped.
Laryngeal muscles of bottlenose dolphin are relativly stonger than those of the
dog, and between muscles dorsally and laterally on the larynx lay venous
plexuses. Cranial and caudal laryngeal nerves of bottlenose dolphin do not
anostomize and 1 did not find superficial branch of cranial laryngeal nerve to
m. cricothyroideus. M. thyroarytenoideus in bottlenose dolphin is platelike and
does not posses mm. vocalis et ventricularis as its special part. 1 also have
not found coresponding ligaments which form the basis for vocal and vestibular
fold which also do not exist in bottlenose dolphin's larynx. Ventraly in the
cavity of larynx median and lateral folds are
present which expand from epiglottic cartilage,
squezees between arytenoids cartilages and continue all the way to trachea.
Between the folds there are small openings which form entrances in small
laryngeal sacs which are situated on the place of the lateral laryngeal sac of
domestic animals.