Histopathologic alterations associated with Anisakis larvae in Pacific herring from Oregon.

A histopathologic study of Anisakis sp. larvae in Pacific herring (Clupea harengus pallasi) is presented. Tissue alterations included mechanical compression of the pancreas and liver, granulomatous inflammation and necrosis of the liver, and trauma to the muscularis externa of the pyloric caeca. Host exudate in most lesions contained macrophages (histiocytes) and lymphocytes.