VRZALOVÁ D., ŠUSTALA M., KRÁSA A., DVOŘÁK R. (2000): Application of maize corn treated with soda lye in diet of fatted steers. EAAP - 51 th Annual Meeting, The Hague 2000: 149. ABSTRACT: An experiment was designed to determine the influence of maize corn treated with soda lye on performance and health of intensively fatted young steers. The trial was carried out on 16 three-month-old steers (8 Holstein – 1; 8 Red pied cattle – 2) of initial average live weight of 140 kg. Steers were fed with basal diet consisted of protein concentrate (1 kg/day), alfalfa hay (1,5 kg/day), maize silage (2-6 kg/day) which was for control groups (A) supplemented with barley flakes (ad lib) and for experimental groups (B) with mixture of barley flakes and soda-lye treated maize corn (1:1) ad libitum. Steers were fed twice a day for 24 weeks. Animals were divided into 4 groups – 1A, 2A, 1B, 2B. ADG in trial for 1A, 1B, 2A and 2B group was following: 1.360; 1.320; 1.520 and 1.630 g, resp. In the metabolic profile of paunch juice and blood the changes indicating a chronical paunch acidosis were observed. The changes were less evident for the groups fed with treated maize corn (1B, 2B) and it shows a positive buffer effect of soda-lye treated maize corn in diet of intensively fatted young steers.