Ciência e Agrotecnologia
Print version ISSN 1413-7054
ZONTA, Márcia Cristina de Mello et al. Metabolizable energy of proteics feedstuffs, determined by the total collection excreta and prediction equations. Ciênc. agrotec. [online]. 2004, vol.28, n.6, pp. 1400-1407. ISSN 1413-7054. http://dx.doi.org/10.1590/S1413-70542004000600024.
A metabolism assay were carried out with broilers in growth phase (traditional method of total collection of excreta) to determinate the nitrogen-corrected apparent metabolizable energy (AMEn) of some feedstuffs, as well as the determination of the energy values by prediction equations published in the national and international pappers. It was determined AMEn of eight fedstuffs, five soybean meal samples and three processed full fat samples (extruded, toasted and micronized). The estimated values were compared with observed, using the Spearman correlation and confidence intervals obtained by the metabolic assay. The energy values of soybean meals samples (1, 2, 3, 4 and 5), full fat soybean extruded, toasted and micronized were 2601, 2650, 2727, 2500, 2426, 3674, 3609, 4296 kcal/kg DM, respectively. Among the studied equations, the AMEn = -822,33 + 69,54CP - 45,26ADF + 90,81EE and AMEn = 2723,05 - 50,52ADF + 60,40EE equation correlated (P<0,05) with AMEn mean value observed in vivo, estimating the largest number of energy values inside of calculated confidence intervals. The equation AMEn = 37,5CP + 46,39EE + 14,9NFE estimated all the samples of soybean meal, as well the equation AMEn = 1822,76 - 99,32CF + 60,50EE + 286,73ash - 52,26starch was good for full fat soybean samples, both equations was correlated (P<0,05). The results obtained in this assay, allow us to conclude that the equation AMEn = -822,33 + 69,54CP - 45,26ADF + 90,81EE and AMEn = 2723,05 - 50,52ADF + 60,40EE shoud be used to predict AMEn values of the studied feedstuffs. The equation AMEn = 37,5CP + 46,39EE + 14,9NFE is more indicated for predict the energy values of soybean meals.
Keywords : Broiler; chemical composition; energy prediction; meal soybean; processed soybean.