Changes

[[Image:Thyroid_crop.jpg|250px|thumb|right|'''The Thyroid gland appears to play an important role in [[Snake Shedding|shedding]] and growth''' - (Copyright © RVC)]]

[[Image:Thyroid_crop.jpg|250px|thumb|right|'''The Thyroid gland appears to play an important role in [[Snake Shedding|shedding]] and growth''' - (Copyright © RVC)]]

==Thyroid==

==Thyroid==

The single thyroid gland is roughly spherical and enclosed in a connective tissue capsule. It lies just cranial to the [[Snake Cardiovascular System|heart]] and ventral to the [[Snake Respiratory System|trachea]]. The thyroid, which is under pituitary control, appears to play an important role in [[Snake Shedding|shedding]] and growth. Accidental [[Lizard and Snake Surgery|surgical]] removal of the thyroid may increase [[Snake Shedding|shedding]], which is the reverse to [[Lizards|lizards]]. In some [[:Category:Snake Species|species]] it has been reported that thyroid extract administration inhibits moulting.

The single thyroid gland is roughly spherical and enclosed in a connective tissue capsule. It lies just cranial to the [[Snake Cardiovascular System|heart]] and ventral to the [[Snake Respiratory System|trachea]]. The thyroid, which is under pituitary control, appears to play an important role in [[Snake Shedding|shedding]] and growth. Accidental [[Lizard and Snake Surgery|surgical]] removal of the thyroid may increase [[Snake Shedding|shedding]], which is the opposite reaction to the one in [[Lizards|lizards]]. In some [[:Category:Snake Species|species]] it has been reported that thyroid extract administration inhibits moulting.

 

==Thymus==

==Thymus==

Reptiles usually have two pairs of thymus glands located cranial to the [[Snake Cardiovascular System|heart]]. They are closely associated with the common carotid artery, jugular vein and vagus nerve.  In [[Snake|snakes]] there are significant [[:Category:Snake Species|species]] differences with some [[Boidae|boids]], [[Colubridae|colubrids]] and crotalids having only a single bilateral lobe.  The thymus decreases in weight with age.

Reptiles usually have two pairs of thymus glands located cranial to the [[Snake Cardiovascular System|heart]]. They are closely associated with the common carotid artery, jugular vein and vagus nerve.  In [[Snake|snakes]] there are significant [[:Category:Snake Species|species]] differences with some [[Boidae|boids]], [[Colubridae|colubrids]] and crotalids having only a single bilateral lobe.  The thymus decreases in weight with age.