The article presents results of experiments conducted at the Institute of Animal Science, v. v. i., focused on stabilizing total mixed rations (TMR) using CitroFor (a combination of citric and formic acid at a 95:5 ratio). Three TMR types were tested (for dry cows, lactating dairy cows, and fresh cows) together with a beef cattle TMR, at temperatures of 20 oC, 30 oC, and under barn conditions. A key finding is that individual TMR types differ markedly in their susceptibility to aerobic deterioration – the dry cow TMR proved the most stable, while the lactating cow TMR was the most problematic. A critical practical insight concerns the importance of correct dosing: the 2 l/t dose proved insufficient and, in the case of fresh cow TMR, even counterproductive, whereas the 4 l/t dose was optimal under consistently high temperatures. Under barn conditions with fluctuating temperatures, the lower dose of 2 l/t may be sufficient. An economic analysis demonstrates that during the summer period (June-September) the investment in a stabilizer (40-60 CZK/t) clearly outweighs the costs of losses caused by aerobic deterioration. The article was produced within the framework of the TAČR TQ11000023 project with support from the institutional project MZE-RO0723.