Duodenal histology and carcass quality of feedlot cattle supplemented with calcium butyrate and Bacillus subtilis

ABSTRACT. The experiment was carried out at the Comigo Technology Center, in Rio Verde, State of Goiás, Brazil, with the objective of evaluating the effects of supplementation with calcium butyrate, as a growth promoting agent for the duodenal mucosa and Bacillus subtilis as a probiotic performance enhancer in feedlot cattle. Calcium butyrate (5 and 10 g per animal per day) and Bacillus (10 g per animal per day) were added to a basal diet. There were used 85 Nelore bulls, with average weight of 315 ± 7 kg. The experiment lasted 118 days, including the adaptation period, until slaughter at 30 months of age. Diets were distributed in a completely randomized design with four treatments, where: T1 = control (basal diet); T2 = basal diet + 5 g calcium butyrate; T3 = basal diet + 10 g calcium butyrate and T4 = basal diet + 10 g calcium butyrate + 10 g probiotic with four replications and five to six animals per replication. It was used a forage: concentrate ratio of 30:70, the roughage used was the corn silage. Height and width measurements of intestinal villi were taken, and carcass and meat quality were evaluated. The supplementation of calcium butyrate and Bacillus subtilis positively influenced (p < 0.05) the carcass marbling level and calcium butyrate increased the villus height in the small intestine.