Thymus Of Animals
Thymus of Ox
The thymus of Ox is a lymphoid organ and is well developed only in the last stages of fetal life and a few months after birth. After birth it undergoes atrophy. In the calf it is pale in colour, distinctly lobulated and consists of thoracic and cervical parts. The thoracic part occupies the greater part of the cranial mediastinal space upto the pericardium. Its left face is in contact with the chest wall and the left lung. Its right face is molded on the great vessels in front of the heart. The cervical part forms the bulk of the gland and consists of right and left lobes, which extend the ventro-lateral aspects of the trachea from the thoracic inlet to the thyroid gland. It weighs about 435 to 600 gm. at five or six weeks of age.
Thymus of Sheep and Goat
Thymus of Sheep and Goat is same as Ox.
Thymus of Horse
In the newborn foal it is greyish pink and consists of right and left lobes. The greater part of the gland is situated in the cranial mediastinum but the two lobes are continued into the neck by a chain of lobules, which lie on the trachea along the course of the carotid artery extending sometimes as far as the thyroid gland. The cervical part however is very variable in horse.
Thymus of Pig
In young ones, it is very large extending to the larynx or even to the mandibular space in thymus of Pig.
Thymus of Dog
Thymus of Dog is small and situated almost entirely in the thoracic cavity. The left lobe is larger than the right.
Thymus of Rabbit
Thymus of Rabbit is same as Of Ox.
Thymus of Fowl
The thymus of fowl is well developed in young chicks; the lobules are extending along the neck on either side.