A 2.5 years old, mixed breed sow presented at the slaughterhouse with a unilateral enlargement of the pinna. When cut, it showed a gelatinous consistency (edematous) and whitish colouration.

Inspectors included neoplastic or inflammatory lesions in the differential.

Histopathological examination helped rule out a diagnosis of neoplasia. It consisted of a dense fibrous tissue proliferation, well structured and vascularized along with the presence of a few mononuclear inflammatory cells around blood vessels.

It is a chronic inflammatory reaction most probably caused by trauma. Similar reactions have been described secondary to trampling or piercing the ears to identify animals with an ear tag.

Mass in the pinna, note the normal looks of the contralateral one.


Internal facet of the pinna.


When sectioned, the mass shows a witish edematous surface.

The lesion consisted mainly on mature fibrous tissue, well differentiated and well vascularized.

The lesion consisted mainly on mature fibrous tissue, well differentiated and well vascularized.

Scarce isolated pyogranulomatous inflammatory foci were identified, but no asteroid bodies nor accumulations of bacteria were observed in any case.

Scarce isolated pyogranulomatous inflammatory foci were identified, but no asteroid bodies nor accumulations of bacteria were observed in any case.