Resumen
The objective of this study was to investigate the effects of supplementation of hydrolyzable tannins (HT) from sweet chestnut wood extract (Castanea sativa Mill.) to the diet of Limousin bulls on growth rate, carcass and meat quality traits, and fecal Clostridia strain levels in a 7-month feeding trial. Thirty-two bulls were randomly assigned to four treatment groups (CON (without addition of HT); TAN 1 (1 g HT kg-1 DM); TAN 2 (1.5 g HT kg-1 DM); and TAN 3 (1.5 g HT kg-1 DM with a nominally lower dose of concentrate). Compared with the CON group, supplementation with HT significantly (p < 0.050) increased bull growth rate during 4?7 months, whereas carcass and meat quality traits were unaffected during the last three months of fattening. Supplementation of HT significantly reduced meat drip loss (p = 0.000) compared with the CON group. No effects were observed on the total number of fecal Clostridia strains; however, the concentration of Clostridium perfringens was significantly lower (p = 0.004) in TAN 1 than that in the CON group. The results obtained in fattening bulls indicate that the addition of HT is justified in practice to improve growth performance and feed efficiency without adverse effects on the carcass and meat quality.