Nowadays, numerous countries are researching feed additives utilisation in pig feed to improve the feed\u27s biological value, increase pig productivity, and increase disease resistance, enhancing pork quality. So, the aim of this study was to determine the influence of a feed additive mixture consisting of yeast cell walls and butyric acid esters on the quality of carcasses and pork from fattening pigs. The feeding test was performed with 32 fattening pigs (65-d-old crossbreeds), which were divided into 2 groups with 4 replicate pens: the control group was fed standard compound feed; the experimental group was fed standard compound feed + 2 kg/t feed additive mixture containing yeast cell walls and butyric acid esters. Pig productivity, muscularity, and fat tissue percentages were assessed during the test. At the end of the trial (179-d-old), 5 fattening pigs were randomly selected from each group and slaughtered; pork carcasses and physico-chemical features were evaluated. The slaughter data of fattening pigs revealed that the carcass weight, carcass yield, longest back muscle area, bacon, and carcass half lengths of the fattening pigs in the experimental group were higher by 1% and 2% compared to the control. However, the feed additive mixture had no significant effect on slaughter data or pork physical or chemical features since no significant difference between the experimental and control groups was discovered (P>0.05). The only indicator of chemical composition that was significantly affected was the ash, which was found to be 0.22% higher in the experimental group compared to the control (P<0.05). According to the obtained results, it can be concluded that the additive, consisting of yeast cell walls and butyric acid esters, used in fattening pigs feed, has no influence on the quality of pork, but it also does not degrade it
