Methods of predicting pale, soft, exudative pork and their application in breeding programmes-A review.

The condition of pale, soft, exudative (PSE) pork has long been considered to be mainly a post mortem phenomenon. There is now substantial evidence that such pigs are suffering from a kind of myopathy, which predisposes them to an abnormal post mortem metabolism. Genetic studies on PSE muscle indicate a moderate heritability for various post mortem muscle quality traits. Reliable methods for determining the abnormal condition in the live animal would make it possible to select more effectively and economically against stress and PSE-susceptibility. Three possible methods are: (1) Analysis of blood serum for CPK, aldolase, GOT or other enzyme activities with and without preceding exercise; and for blood groups. (2) Muscle biopsy analysis for glucose-6-phosphate, lactate or energy-rich phosphates. (3) Non-destructive testing of young pigs for sensitivity to the Malignant Hyperthermia Syndrome by allowing them to inhale the anaesthetic halothane (fluothane) for a 5 min period. The development of muscular rigidity and stiffness indicates a susceptibility to stress and a potential for PSE meat. The relationships of the various methods to ultimate muscle and carcass quality, as well as the problems inherent to each method, are discussed. It is concluded that the third test seems to be the most promising for application in the breeding of pigs for optimal stress resistance and muscle quality.