We recently received inquiries regarding the presence of hemorrhagic lesions in the skin of swine carcasses that often come with a presumptive diagnosis of Porcine Dermatitis and Nephropathy Syndrome (PDNS).

In both cases illustrated here (Figures 1 and 2), the lesion is probably caused by a state of haemorrhagic diathesis or due to manipulations occurred during or around the time of slaughter.

The differential diagnosis are:

  • Porcine Dermatitis and nephropathy syndrome (PDNS) in the case of the PDNS typical necrotizing lesions can be observed which usually have a central black area of discoloration. Often, to some degree, renal lesions can be noticed (particularly: increased kidney volume and renal petechiae).
  • Erysipelas or “Diamond skin disease” (Erysipelothrix rhusiopathiae): Lesions show a very characteristic “diamond” morphology. Chronically Erysipelas can be associated with endocarditis or arthritis, but without skin involvement.
  • Classical and African swine fever: widespread hemorrhage and sudden death. The animals usually have high fever.
  • Other skin conditions: Dermatophytosis, Pityriasis rosea, Swine pox, exudative epidermitis.

 

Extensive skin haemorrhages, which mainly affect the ventral side of the carcass.

Extensive skin haemorrhages, which mainly affect the ventral side of the carcass.

Generalized petechial hemorrhages in the skin and fat.

Generalized petechial hemorrhages in the skin and fat./caption]

[caption id="attachment_630" align="alignnone" width="550"]PDNS typical lesions in a pig, the distribution is  focused on the hindquarters and lesions have central area of black discoloration which corresponds to necrosis. PDNS typical lesions in a pig, the distribution is focused on the hindquarters and lesions have central area of black discoloration which corresponds to necrosis.