ABSTRACT. An experiment was carried out to investigate the effect of multi-enzyme in high and low levels of metabolizable energy (13.81 and 11.51 MJ kg-1 diet) on performance and energy utilization of broilers fed wheat-soybean meal diets from 0 to 21 days of age. Result showed that birds fed diets containing 11.51 MJ kg-1 consumed significantly (p < 0.05) more feed than diets containing 13.81 MJ kg-1, whereas daily gain and feed conversion ratio improved (p < 0.05) when enzyme was added to 11.51 MJ kg-1 diet. There was significant improvement in metabolizable energy, net energy for production, organic and dry matter digestibility in 0-21 when diets supplemented with enzyme (p < 0.05). Addition of enzyme to 11.51 MJ kg-1 containing diet significantly (p < 0.05) reduced heat production of birds in 0-10 d, whereas heat production was not changed in 21 days. Supplementation of 11.51 MJ kg-1 diet with enzyme improved the efficiency of ME use for carcass energy and protein retention of broilers (p < 0.05). Generally, the results of current study demonstrated that addition of enzyme to wheat-soybean diets improved NEp of broiler chickens while MEI was not changed and it seems NEp is a more sensitive energy utilization response criterion to use in evaluating broilers response to enzyme supplementation.

RESUMO. Este estudo avaliou o efeito de três valores da matriz para nutriente multi-enzimático e comparou os resultados com os obtidos com dietas baseadas em cevada e milho sem enzima. Em todo o período, a adição de todas as enzimas à dieta à base de cevada aumentou significativamente (p < 0,05) a ingestão de ração, sendo a maior ingestão observada nas aves alimentadas com a enzima A (p < 0,05). No geral, de 0 a 42 dias, o ganho médio diário foi significativamente aumentado (p < 0,05) pelo uso de enzimas e as aves alimentadas com a enzima A apresentaram o maior peso corporal (p < 0,05). De modo geral, de 0 a 42 dias de idade, o índice de conversão alimentar foi significativamente maior (p < 0,05) com a adição de enzima à dieta a base de cevada, mas sem diferenças significativas entre as dietas contendo enzimas A e C e à dieta a base de milho. O peso da carcaça e o peso relativo da gordura abdominal foram significativamente aumentados pela enzima, enquanto o intestino delgado e o ceco diminuíram com a adição de enzima (p < 0,05). A adição de enzima reduziu significativamente a viscosidade do jejuno no dia 23 (p < 0,05), ao passo que o pH da digesta jejunal não foi alterado (p > 0,05). A umidade da cama e a razão água: ração aos 15, 25 e 33 dias de idade foram significativamente reduzidos pela adição de todas as enzimas (p < 0,05). Em conclusão, considerando os valores da matriz de nutrientes para todas as enzimas utilizadas melhoraram o desempenho de frangos de corte, indicando que podem ser utilizadas na formulação de dietas à base de cevada para frangos de corte comerciais.

ABSTRACT. In this study, we have evaluated the effect of three multi-enzymes nutrient matrix values and compared the results with that fed barley and the corn diets without enzyme. In entire period, addition of all enzymes to the barley-based diet significantly (p < 0.05) increased feed intake (FI) and the highest intake was for birds that fed enzyme A (p < 0.05). Overall, from 0 to 42 days, average daily gain (ADG) was significantly (p < 0.05) increased by enzyme and birds fed enzyme A had the highest body weight (p < 0.05). Generally, from 0 to 42 d of age, feed conversion ratio (FCR) was significantly (p < 0.05) improved when enzyme added to barley-based diet, but there were no significant differences among diets containing enzymes A and C and the corn-based diet. The carcass weight, and the relative weight of the abdominal fat were significantly increased by enzyme, while small intestine and cecum decreased with enzyme addition (p < 0.05). Enzyme significantly decreased jejunal viscosity at Day 23 (p < 0.05), whereas pH of jejunal digesta was not changed (p > 0.05). Litter moisture and water to feed ratio at 15, 25, and 33 days of age significantly decreased by addition of all enzymes (p < 0.05). In conclusion, considering nutrient matrix values for all used enzymes improved performance of broilers and can be used in formulating diets commercial broiler diets based on barley.