Diets high in saturated fatty acids (SFAs) and n-6 polyunsaturated fatty acids (PUFAs) at the expense of n-3 PUFAs have been shown to increase the risk of cardiovascular disease, obesity and cancer. Animal fat is considered to be the major source of unhealthy saturated fats. However, beef fat has a high nutritional value due to the presence of minerals, PUFAs, vitamins and selected protein fractions. The aim of this study was to determine the effect of fattening intensity on the fatty acid profile and mineral content of meat from Holstein-Friesian bulls. Holstein-Friesian bulls aged 11 to 19 months were fattened under semi-intensive (SI, 10 animals) and intensive (I, 10 animals) systems. The bulls were fed maize silage, rapeseed meal and premix ad libitum. The diets for group I animals were supplemented with 2.5 kg ground triticale provided in an automatic feeding station. Meat samples were collected from m. longissimus dorsi (MLD). The samples were mineralized and assayed for mineral content. Fat was extracted from each sample, and the fatty acid profile of beef was determined by gas chromatography. Dietary supplementation with ground triticale increased the average daily gains of bulls and carcass dressing percentage, and contributed to higher carcass conformation and fat cover scores. Beef was found to be a rich source of valuable mineral compounds. The meat of group I animals was characterized by higher potassium levels and lower sodium levels, which points to its higher nutritional value. Semi-intensive (SI) fattening increased PUFA concentrations and decreased the n-6/n-3 PUFA ratio in beef.  

22.4.2016