Porcine Stress Syndrome

• Malignant hyperthermia
• Pigs, dogs, humans
• Possibly a cellular defect resulting in high intacellular calcium ion concentration
  • -> Activates myofibrillar ATPase -> rapid intracellular glycolysis -> increase in body heat -> denature protein -> cell death -> leakage of cellular content -> oedema
• Grossly:
  • Muscles are pale, soft and exudative
• Histologically:
  • Segmental hypercontraction
  • Monophasic, multifocal segmental necrosis
• Inherited
• Triggered by halothane anaesthesia, stress of handling, transportation or slaughter