The bronchial tree and lobular division of the horse lung.

The research investigates the bronchial structure and lobular division of horse lungs, suggesting that in addition to the existing cranial and caudal lobes, the horse lung can be divided into four lobes: cranial, middle, caudal, and accessory.

Investigation of Horse Lungs

• The study involved examination of the lungs of five horses to determine the structural difference in domestic animals’ respiratory systems.
• Typically, veterinary anatomy divides a horse’s lung into a cranial and caudal lobe on each side of the cardiac notch. But this research claims the possibility of further divisions based on bronchial branching.

Bronchial Branching and Lobes

• The report suggests, from a bronchial view, that horse lungs can be divided into four lobes bilaterally – namely, cranial, middle, caudal, and an accessory lobe.
• According to the authors’ findings, the horse lung has four bronchiolar systems on either side, namely dorsal, lateral, ventral, and medial.
• The first bronchiole of the dorsal bronchiolar system forms the cranial lobe, the first bronchiole of the lateral bronchiolar system forms the middle lobe, and the first bronchiole of the ventral bronchiolar system forms the accessory lobe.
• The remaining bronchioles of the dorsal, lateral, and ventral bronchiolar systems, along with all bronchioles of the medial bronchiolar system, constitute the caudal lobe.

Comparison with Other Domestic Animals

• The findings from the horse lungs were compared to the structural features of the lungs in other domestic animals.
• This comparison helps in determining the unique features of a horse’s lung, although the report does not specify the differences identified or the animals these observations were compared with.