Effect of a low protein : energy nutritional strategy on intramuscular and subcutaneous fatty acid content, and stearoyl-CoA desaturase protein expression in Large White and Duroc pigs

Extract

The production of pigs with low subcutaneous but high intramuscular fat (IMF) is one of the main challenges of the pig industry, and it requires the understanding of the mechanisms controlling fat formation in these two depots. IMF can be increased by reducing the ratio of protein to energy in pig diets (Wood et al.,, 2004). This is accompanied by activation of expression of the enzyme stearoyl-CoA-desaturase (SCD), which catalyses the biosynthesis of monounsaturated fatty acids (MUFA) (Doran et al., 2006). It is well known that IMF content varies between breeds. However it remains unclear as to whether pigs with predominantly high IMF (e.g. Duroc) will respond to a low protein diet in the same way as those with predominantly low IMF (e.g. Large White). The objective of the present study was to investigate whether the effects of low protein: energy diets on IMF, MUFA and total fatty acid content are breed-specific.