Left pancreatic lobe

The left lobe of the pancreas extends toward the left side of the body, usually in close relation to the greater curvature of the stomach and the spleen. It is typically thinner and more elongated compared to the right lobe. The lobe contains parenchymal tissue responsible for both exocrine (digestive enzyme production) and endocrine (hormone secretion) functions.

Topographical Relations

• Dog and Cat: The left lobe lies within the deep leaf of the greater omentum, along the greater curvature of the stomach and medial aspect of the spleen. It runs cranially and slightly medially toward the splenic hilum.

• Horse: The left lobe is elongated and lies dorsally along the lesser curvature of the stomach. It is more superficial in comparison to ruminants and closely associated with the splenic artery.

• Ox (Cattle): The left lobe is relatively smaller and extends toward the left side beneath the rumen, near the greater curvature of the abomasum. It lies adjacent to the spleen and left longitudinal groove of the rumen.

• Pig: The pancreas is more compact and ring-shaped. The left lobe still projects toward the stomach and spleen but is somewhat shorter and bulkier.

Vascular and Duct Relations

• The left lobe is supplied by branches of the splenic artery and vein.

• The main pancreatic duct (or accessory duct, depending on species) may traverse or be adjacent to the left lobe before merging into the duodenum.

• Lymphatics from the left lobe drain into pancreaticosplenic and gastric lymph nodes.

Species Differences Summary

• Dogs and cats: More prominent and functional left lobe.

• Horses: Long, slender lobe located dorsally.

• Ruminants: Left lobe is reduced and less distinct.

• Pigs: Integrated into a compact pancreatic structure with minimal lobar distinction.