Transverse colon

The transverse colon is a segment of the large intestine in domestic animals that connects the ascending colon to the descending colon. It traverses the abdominal cavity from right to left, usually passing cranial to the root of the mesentery, and is a relatively short but crucial portion of the intestinal tract involved in water absorption and fecal formation.

Anatomical Features and Species Variations

• General Structure: The transverse colon is often supported by its own mesentery, the transverse mesocolon, and is composed of smooth muscle with mucosal folds to enhance absorption.

• In Ruminants (e.g., cattle, sheep, goats): It lies between the centripetal and centrifugal coils of the colon, running transversely in the cranial abdomen. Due to the complexity of the ruminant colon, it is relatively short and less distinct.

• In Equines (horses): The transverse colon is found between the right dorsal colon (a portion of the ascending colon) and the small colon (descending colon). It runs from the right dorsal abdominal region to the left, passing cranial to the cranial mesenteric artery.

• In Carnivores (dogs and cats): The transverse colon is relatively straight and short, passing from right to left and lying just cranial to the cranial mesenteric artery.

• In Swine: Similar in position to that of carnivores, though slightly more convoluted due to the general spiral configuration of the porcine colon.

Function

The transverse colon primarily functions to:

• Absorb remaining water and electrolytes from digesta,

• Compact fecal matter,

• Transport content towards the descending colon for eventual excretion.