Addition of an enzymatic complex to a sorghum mixture with different granulometries and its effect on nitrogen digestibility and metabolizable energy of birds

Abstract

In order to evaluate the effect of the addition of an enzymatic complex in a sorghum mixture on the true digestibility of nitrogen (TND) and metabolizable energy (TME) of roosters, an experiment with 56 roosters of Bovans Brown breed were used. Three levels of granulometry (G) were established (1, 3 and 5 mm). Six treatments were developed: T1) sorghum mixture without enzymatic complex + G 1 mm; T2) sorghum mixture with enzymatic complex + G 1 mm; T3) sorghum mixture without enzymatic complex + G 3 mm; T4) sorghum mixture with enzymatic complex + G 3 mm; T5) sorghum mixture without enzymatic complex + G 5 mm and T6) sorghum mixture with enzymatic complex + G 5 mm. A completely randomized design, with a factorial arrangement of 3 x 2 and 8 roosters (repetition) per treatment, was used. There were no statistical differences for factors of granulomtry and presence or not of the enzymatic complex in the TME (16.04 MJ/kg DM). For TND, there was interaction with the between the enzimatic complex and the granulometry (P < 0.001). T4 had the highest digestibility (95.82 ± 1.66 %) and T2 had the lowest (83.43 ± 2.71 %). It can be concluded that adding the enzymatic complex do not affect the evaluated variables. However, it is recommended to use the sorghum mixture with granulometry of 3 mm, because it maintains the TME and increases the TDN.

Key words: exogenous enzymes, diets, rosters, particle size, tannins