Determinação dos valores energéticos e aminoacídicos da silagem de grãos úmidos de milho para frangos de corte

To determine the energy values of high moisture corn silage (SGUM), 120 Cobb Slow male broilers from 21 to 31 days old, with an initial average weight of 765.0 ± 1.7 g, were used, distributed in a completely randomized design, with five treatments (reference ration-RR and replacement levels of SGUM 10, 20, 30 and 40%), in six replicates of four birds each. The experimental period lasted for ten days, five for adaptation and five for collection. The method of analysis was the total excreta collection for the subsequent analysis of its apparent metabolizable energy (EMA) and nitrogen corrected EMA (EMAn) of SGUM. To determine the amino acid values, the technique of forced feeding was applied in 12 cecectomized Leghorn roosters, with an average weight of 1912.10 ± 133.73 g. Six animals received SGUM and the other six were fasted. At the end of the excreta collection period, the essential amino acid profile was determined, as well as, the true digestibility coefficients and the true digestible content of amino acids in the feed. SGUM presented average values of EMA and EMAn of 2283 and 2272 kcal/kg, respectively, and the energy values were negatively affected by the inclusion levels of SGUM. Cystine presented the lowest digestibility coefficient, whereas leucine and glutamine showed the highests digestible amino acids values.Para a determinação dos valores energéticos da silagem de grãos úmidos de milho (SGUM), foram utilizados 120 frangos de corte machos, linhagem Cobb Slow, de 21 a 31 dias de idade, com peso médio inicial de 765,0 ± 1,7 g, distribuídos em um delineamento inteiramente casualizado, com cinco tratamentos (ração referência-RR e níveis de substituição da SGUM de 10, 20, 30 e 40 %), seis repetições e quatro aves por unidade experimental. O período experimental teve duração de dez dias, sendo cinco de adaptação e cinco de coleta. O método de análise foi o de coleta total de excretas, para posterior análises de energia metabolizável aparente (EMA) e EMA corrigida pelo balanço de nitrogênio (EMAn) da SGUM. Para a determinação dos valores de aminoácidos, foi usada a técnica de alimentação forçada em 12 galos Leghorn cecectomizados, com peso médio de 1912,10 ± 133,73 g. Seis animais receberam a SGUM e os outros seis permaneceram em jejum. Ao final do período de coleta de excretas, foi determinado o perfil de aminoácidos essenciais, coeficientes de digestibilidade verdadeira e o conteúdo digestível verdadeiro dos aminoácidos no alimento. A SGUM apresentou valores médios de EMA e EMAn de 2283 de 2272 kcal/kg, respectivamente, sendo que os valores energéticos foram negativamente influenciados pelos níveis de inclusão da SGUM. A cistina apresentou o menor coeficiente de digestibilidade, enquanto a leucina e a glutamina apresentaram os maiores valores de aminoácidos digestíveis

Coeficientes energéticos de alimentos de origem vegetal determinados com frangos de corte em diferentes idades

In order to determine the apparent metabolizable energy (AME), the AME corrected for nitrogen balance (AMEn), the apparent coefficients of metabolization (ACM) of gross energy and the ACM corrected for nitrogen balance (ACMn), an experiment was conducted to evaluate five different plant foods (corn, soybean meal, deactivated full-fat soybean, wheat bran and soybean oil) for broilers at different ages (1-8, 11-18, 21-28, 31-38 and 41-48 days). The method of total excreta collection was used, divided into five metabolism assays. The birds were housed in metabolic cages in a completely randomized design, with five treatments and five replicates per treatment, totaling 25 experimental units. The AME and AMEn values increased with the age of the birds for most foods, except soybean meal. The smaller AMC and AMCn of gross energy were obtained for wheat bran. There was adjustment of the equation to the linear response plateau model for the ACM of corn, soybean meal and deactivated full-fat soybean. The wheat bran and soybean oil were adjusted to the linear regression model. The equations show that the digestibility of energy tends to increase with age, except for soybean meal, which had higher metabolization with younger birds. We conclude that the age of the birds influences the determination of the metabolizable energy of feed.O objetivo deste trabalho foi determinar os valores de energia metabolizável aparente (EMA), os valores de EMA corrigida para o balanço de nitrogênio (EMAn), os coeficientes de metabolizabilidade aparente (CMA) da energia bruta e os CMA corrigidos para o balanço de nitrogênio (CMAn) de cinco diferentes alimentos de origem vegetal (milho, farelo de soja, soja integral desativada, farelo de trigo e óleo de soja) com frangos de corte em diferentes idades (1 a 8, 11 a 18, 21 a 28, 31 a 38 e 41 a 48 dias). Foi utilizado o método de coleta total de excretas. Os frangos foram distribuídos em um delineamento inteiramente casualizado, com cinco tratamentos e cinco repetições cada, totalizando 25 unidades experimentais. Os valores de EMA e EMAn aumentaram com a idade das aves para a maioria dos alimentos, exceto para o farelo de soja. O menor CMA e CMAn da energia bruta foi obtido com o farelo de trigo. Houve ajuste das equações ao modelo LRP para o CMA do milho, farelo de soja e soja integral desativada. O farelo de trigo e o óleo de soja se ajustaram ao modelo de regressão linear. As equações demonstram que a metabolizabilidade da energia tende a aumentar com a idade, com exceção do farelo de soja, que teve maior metabolizabilidade com aves mais jovens. Conclui-se que a idade das aves influencia na determinação dos valores de energia metabolizável dos alimentos

Performance of broiler chickens at pre starter and starter phases using diets with different metabolizable energy values of ingredients, at different ages

ABSTRACT: The experiment was carried out to evaluate the performance of broilers in 1-7 and 8-21 days of age, using metabolizable energy values of corn, soybean meal and soybean oil previously determined for each phase in another metabolism trial. Two trails were conducted, divided into phases according to ages: pre-starter (1-7 days) and starter (8-21 days). At each trial were used 924 broiler chicken randomly distributed into 42 experimental units in a completely randomized design with six treatments and seven replications. Treatments consisted of five diets using the values of apparent metabolizable energy corrected for nitrogen balance of corn, soybean meal and soybean oil determined in different metabolism trials, and one diet with the metabolizable energy values of these same ingredients, published on the literature. At the end of each stage, the animals and feed leftover were weighted to determine feed intake, weight gain and feed conversion ratio. Diets with higher soybean oil inclusion, showed superior performance at different stages. At pre-starter only feed conversion ratio was significant (P<0.05). In the initial phase, there was a significant difference (P<0.05) for feed conversion ratio, daily and average weight gain

Bioavailability of different methionine sources for growing broilers

The objective of this trial was to evaluate the bioavailability of DL-2-hydroxy-4-(methyl) butanoic acid (DL-HMBA) and a polyherbal ingredient (PHI) in relation to DL-methionine (DLM) on broilers. Nine hundred male broiler chickens of the Cobb 500 strain were fed from 22 to 42 days of age either a basal diet without industrial methionine supplementation or the basal diet supplemented with DL-HMBA at one of three levels (0.143, 0.286 and 0.429%) or DLM at one of three levels (0.093, 0.186 and 0.279%, each of which is 65% of the respective DL-HMBA level by weight) or PHI at one of the same three levels used for DLM (0.093, 0.186 and 0.279%). The weight gain, feed conversion ratio and relative weights of breast and abdominal fat were improved over that of basal diet-fed broilers by the addition of DL-HMBA and DLM to the diet. A simultaneous exponential regression analysis revealed that the relative bioavailability values for DL-HMBA and PHI were 52% and 5% of that of DLM, respectively, for weight gain, and 57% and 4%, respectively, for feed conversion ratio. Concerning breast meat yield, a simultaneous linear regression analysis (slope ratio) showed that the relative bioavailability for DL-HMBA was 65% of that of DLM. Considering all studied parameters together, the relative bioavailability values for DL-HMBA and PHI are 58% and 4.5% of that of DLM on a product basis