Selenium supplementation in Pampa Rocha pigs enriches the meat, improves its oxidative status and modifies the fatty acid composition

Abstract

The Pampa Rocha (PR) pig is a native resource, adapted to the Uruguayan biotope. In the search to obtain a differential meat product through the production system, and functional for its nutritional contributions, PR pigs were supplemented with selenium (Se), organic (SO) and inorganic (SI) in an outdoor system with access to pastures. The Se content, fatty acids (FA) composition, oxidative status, and health indices (atherogenic, thrombogenic, and hypocholesterolemic/hypercholesterolemic index) of the Psoas Major (PM) muscle were studied. Twenty-four castrated male pigs were randomly divided into three groups of eight animals per treatment: control (C), SO, and SI, which was applied from days 90 to 182. The Se supplementation was 0.3 ppm for both sources. Immediately after slaughter, the PM muscle was extracted. The Se was determined by atomic spectrophotometry (PerkinElmer AA300), FA using a capillary column and a PerkinElmer Clarus500 chromatograph. Oxidative status was determined using the TBARs-MDA method, and health indices were estimated based on FA composition. The meat was enriched with Se when the animals were supplemented with SO (0.53 vs. 0.27 mg/kg of meat in C). Se modified the C14:0 content in meat (an FA important important for health due to its atherogenic effect), which was lower in animals supplemented with SI (0.88% vs. 0.98% in the C). However, this modification was insufficient to impact the calculated health indices. Selenium supplementation modified the oxidative status of the PM muscle, resulting in lower levels of MDA in the meat of SI supplemented animals compared to the C (0.29 vs. 0.47 mg MDA/kg of meat, respectively). Supplementation with Se enriched the meat with the SO source. The incorporation of SI altered the FA composition of the meat (particularly C14:0) without affecting health indices. In addition, supplementation with its inorganic form improved the oxidative stability of the PM muscle.