In a 7 months old, male, crossbreed pig carcass multifocal areas were observed at the ventral subcutaneous adipose tissue with presence of black filamentous lesions.

Histopathological study showed the deposition of a brownish-black pigment (melanin) around the mammary gland ducts and blood vessels. This condition is known as melanosis uberis and has been described in pigs and bears. It is probably a congenital defect.

Black miliary lesions in the  subcutaneous fat of the ventral region.

Black miliary lesions in the subcutaneous fat of the ventral region.

At a closer look one can observe that the black spots show a filamentous pattern, tracing mammary ducts and/or vessels.

At a closer look one can observe that the black spots show a filamentous pattern, tracing mammary ducts and/or vessels.

Subepitelial, pigment-laden melanocytes (arrowheads). Pigment-laden macrophages near blood vessels (arrow).

Subepitelial, pigment-laden melanocytes (arrowheads). Pigment-laden macrophages near blood vessels (arrow).