Reducing the incidence of low quality (PSE) pork with vitamin-mineral nutritional modulation

The pork industry is a part of the high volume meat industry. Pork comprises 40% of all meat produced in the world (Hovenier et al., 1993). Problems with pork, in comparison to veal or poultry, are the large variation in quality and the undesirable health image, mainly because of pork being too fat (Sebranek, 1982). Pork producers attempted to change this image in the 1950's by instituting breeding programs designed to lower the fat content of pork carcasses. In reality, producers were seeking to produce a trim, muscular "meat type" hog. The change improved the fat and lean content of the pig, but this selection caused an unexpected change in the quality of muscle (Kauffman and National Pork Producers Council, 1992).

The main improvement in carcass composition was produced by introducing the halothane gene (porcine stress syndrome, PSS) into the gene pool. While certainly improving carcass muscling, the introduction of the halothane gene made the pigs more susceptible to quality problems related to PSE pork, particularly a reduction in waterholding capacity of muscle. Additionally, meat from halothane positive (homozygous recessive) animals has undesirable palatability. especially tenderness and juiciness, compared to meat from halothane negative (homozygous dominant) pigs (Boles et al., 1991).