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Bulls, Czech Red-Pied × Ayrshire × Red Holstein crossbreds (initial live weight 90 kg), fed the basal diet supplemented with production mixture containing either soybean meal (SBM; control group; 11 animals) or heat-treated rapeseed cake (HRC; experimental group; 12 animals) were fattened to the age of 16 months. The difference between live weight of SBM bulls (546 kg) and HRC bulls (569 kg) at the end of fattening was not significant ( P > 0.05). Loin (musculus longissimus lumborum et thoracis) and tallow samples were taken from each animal after slaughter and 15 fatty acids were determined by gas chromatography after lipid extraction with diethyl ether. No impairment of health status was observed in HRC-bulls as compared with the control group. Lipid contents in the loin of HRC-bulls (4.17%) and con- trol bulls (3.69%) did not differ (P > 0.05). The percentage of total saturated fatty acids (SFA; 46.2%) was lower (P < 0.05) and the percentage of oleic acid (C18:1; 46.9%) was higher (P < 0.05) in loin lipids of HRC-bulls in comparison with SBM-group (49.0% and 48.2%, respectively). SFA/MUFA (monounsaturated fatty acid) ratio and C16/C18 ratio in loin lipids was lower (P < 0.05 and P < 0.01, respectively) in HRC-group than in the control group. Total polyunsatu- rated fatty acid (PUFA) percentage in the loin of HRC-bulls was higher (P < 0.05) than in bulls receiving SBM (3.3 and 2.8%, respectively). The SFA/PUFA ratio was also more favourable (lower, P < 0.01) in the loin of experimental group as compared with SBM-bulls. SFA deposition in the loin of HRC-bulls was lower (P < 0.001) and that of MUFAs was higher (P < 0.001) than in tallow. It was concluded that from the viewpoint of human nutrition, the following markers of the nutritive value of beef meat are more favourable than in poultry meat (based on the present and previous experi- ments): arachidonic acid content (<5 mg/100 g of fresh tissue and 53-73 mg/100 g, respectively) and PUFA n-6/PUFA n-3 ratio (4.3 and 10-12, respectively).