• Porcine Stress Syndrome (PSS) or Malignant Hyperthermia (MH)

The Porcine Stress Syndrome (PSS) or Malignant Hyperthermia (MH) is an inherited neuromuscular disorder in pigs. Under stress conditions, pigs affected with this syndrome present fast post-mortem changes in muscles, with meat of poor quality associated with Pale, Soft and Exudative pork (PSE), or even sudden death before slaughtering. PSS is triggered when animals are subjected to stress, such as transport, sexual intercourse, vigorous exercise, or even changes in environmental conditions. The genetic origin of PSS is a mutation in the gene for calcium release channel (Ryr1). Recessive allele (n) is responsible for physiological reactions. So, recessive homozygote (n/n) leads to porcine stress syndrome (PSS). In heterozygosis (N/n) it is linked to poor meat quality.