Effect of dietary acetic acid levels on protein and energy utilization in chicks.

Chicks were given diets containing varying amounts of dietary acetic acid (0, 12.7, 25.4, 38.1, 50.8, and 63.5 g/kg diet) under ad libitum feeding in Experiment 1 and under equalized feeding (average feed intake of Experiment 1) conditions in Experiment 2. In Experiment 1, values for body weight gain (g/10 days), feed intake (g/10 days), fat retention (g/10 days), and energy retention (kJ/10 days) were linearly lower as dietary acetic acid was increased. In Experiment 2, values for body weight gain, protein retention, and fat retention (grams/10 days), and for energy retention (kiloJoules/10 days) were changed curvilinearly. These values tended to increase until diets contained 25.4 g acetic acid/kg diet and then decreased significantly when diets contained 50.8 g acetic acid/kg diet. All chicks given the 63.5-g acetic acid/kg diet died during Experiment 2. Dietary acetic acid had a detrimental rather than a beneficial effect on chick performance, particularly at the high level.