Composição química e energética de alimentos de origem vegetal determinada em aves de diferentes idades Chemical and energetic composition of feedstuffs of plant origin for poultry at different ages

Foram realizados quatro ensaios para determinar a energia metabolizável aparente (EMA) e a energia metabolizável aparente corrigida pelo balanço de nitrogênio (EMAn) de dez alimentos de origem vegetal para aves em diversas idades. Os alimentos estudados foram: farelo de soja 45%, farelo de soja 48%, soja integral extrusada, soja integral desativada, soja integral micronizada, farinha de soja desativada, concentrado proteico de soja, farelo de glúten de milho 21%, gérmen de milho e quirera de arroz. Utilizou-se o método de coleta total de excretas, em delineamento experimental inteiramente casualizado, com 11 tratamentos e 6 repetições nos quatro ensaios. No primeiro, segundo e terceiro ensaios, foram utilizados frangos de corte com 10 a 17; 26 a 33; e 40 a 47 dias de idade, respectivamente, e no quarto ensaio galos com 25 semanas de idade. Os valores de EMAn (kcal/kg), na matéria natural, determinados no primeiro, segundo, terceiro e quarto ensaios foram, respectivamente: 2.069, 2.148, 2.272 e 2.231 para o farelo de soja 45%; 2.214, 2.225, 2319 e 2.247 para o farelo de soja 48%; 3.322, 3.331, 3.405 e 3.493 para a soja integral extrusada; 3.016, 3.067, 3.139 e 3.388 para a soja integral desativada; 3.557, 3.638, 3.828 e 3.869 para a soja integral micronizada; 2.292, 2.348, 2.518 e 2.502 para a farinha de soja desativada; 2.356, 2.399, 2.509 e 2.486 para o concentrado proteico de soja; 1.826, 1.882, 2.110 e 1.942 para o farelo de glúten de milho 21%; 2.605, 2.764, 2.925 e 2.832 para o gérmen de milho; e 2.967, 3.029, 3.096 e 3.026 para a quirera de arroz.<br>Four assays were carried out to determine the apparent metabolizable energy (AME) and nitrogen corrected apparent metabolizable energy (AMEn) of ten feedstuffs of vegetable origin for poultry at different ages. The chemical composition of the ten feedstuffs was also determined: 45% soybean meal, 48% soybean meal, extruded full-fat soybean, deactivated full-fat soybean, micronized full-fat soybean, deactivated soybean meal, soybean protein concentrate, corn gluten meal 21%, corn germ and broken rice. The method of total excreta collection was used and a randomized complete experimental design was used with 11 treatments and six replications, in the four assays. In the 1st, 2nd and 3rd assays broiler chicks were used aged 10 to 17, 26 to 33 and 40 to 47 days, respectively, and in the 4th assay roosters were used with 25 weeks of age. The AMEn values (as-fed basis) determined in the 1st, 2nd, 3rd and 4th assay were, respectively: 2069, 2148, 2272 and 2231 for 45% soybean meal; 2214, 2225, 2319 and 2247 for 48% soybean meal; 3322, 3331, 3405 and 3493 for extruded full-fat soybean; 3016, 3067, 3139 and 3388 for deactivated full-fat soybean; 3557, 3638, 3828 and 3869 for micronized full-fat soybean; 2292, 2348, 2518 and 2502 for deactivated soybean meal; 2356, 2399, 2509 and 2486 for soybean protein concentrate; 1826, 1882, 2110 and 1942 for corn gluten meal 21%; 2605, 2764, 2925 and 2832 for corn germ; and 2967, 3029, 3096 and 3026 for broken rice.