Walter Amaral Barboza

Desempenho de frangos de corte, digestibilidade de nutrientes e valores energéticos de rações formuladas com vários milhos, suplementadas com enzimas

Two assays were carried out to evaluate the broilers performance, nutrients digestibility and the energy values of diets formulated with corn from different varieties (Experiment 1) and regions (Experiment 2), supplemented with an enzymatic complex. In each assay, were used 480 male broilers Hubbard, 14 days old, grown from 14 to 27 days to evaluate performance. The broiler chickens fed an experimental diets in 6x2 factorial design (varieties x region), in four replicates of 10 broilers in each experimental unit. Each corn were mixed in a basal diet in a fixed amount of 63.24%, constituting the experimental diets. The crude protein and energy values changed according to corn composition. Chromic oxide (0.5%) was used as indicator. During the 23rd to 27th days, the excretas were collected and, in the 28th day, all broilers of each replicate were slaughtered and the digesta present in the last 30 cm of the terminal ileum, anterior to ileo-cecal junction, was collected. The samples of the excreta and ileal digesta were analyzed for dry matter, nitrogen, gross energy and starch, and the digestibility coefficients and energy values, were calculated using the indigestibility factor of chromic oxide. It was concluded that origen (varieties or regions) effected broiler performance; the nutrient digestibility and energy values of diets formulated with the corn type showed difference as a function of the chemical composition. The ileal digestibility of crude protein, starch and energy was improved in the diets supplemented with enzymes.

Níveis de lisina para frangos de corte de 1 a 21 e 15 a 40 dias de idade

Two experiments were carried out to determine the nutritional requirement of total lysine for Hubbard and Ross broiler chickens of both sexes, from 1 to 21 and from 22 to 40 days of age. The evaluated traits were weight gain, feed intake, feed:gain, carcass yield, breast with bone yield, breast meat yield and fat pad. In each phase, a completely randomized block experimental design in a 2 x 2 x 6 factorial arrangement was used, with two sexes, two trade mark and six dietary lysine levels, with four replicates using a total of 1920 birds. The basal diets with 1.0% of lysine, 22.61% CP and 3050 kcal ME/kg in the first experiment and 0.825% lysine, 19.6% CP and 3200 kcal ME/kg in the second experiment, were supplemented with six lysine levels (0, 0.06, 0.12, 0.18, 0.24 and 0.30%). Considering the traits as weight gain, feed: gain, the dietary requirement estimates for the phase from 1 to 21 days were 1.191% and 1.198% total lysine for males and females Ross and 1.174% and 1.188% of total lysine for males and females Hubbard, respectively. For the period from 15 to 40 days, considering the weight gain, feed:gain ratio, carcass yield, breast with bone yield, breast meat yield and fat pad, the dietary total lysine level of 1.125% was considered adequate for both sexes from the two trade marks.Two experiments were carried out to determine the nutritional requirement of total lysine for Hubbard and Ross broiler chickens of both sexes, from 1 to 21 and from 22 to 40 days of age. The evaluated traits were weight gain, feed intake, feed:gain, carcass yield, breast with bone yield, breast meat yield and fat pad. In each phase, a completely randomized block experimental design in a 2 x 2 x 6 factorial arrangement was used, with two sexes, two trade mark and six dietary lysine levels, with four replicates using a total of 1920 birds. The basal diets with 1.0% of lysine, 22.61% CP and 3050 kcal ME/kg in the first experiment and 0.825% lysine, 19.6% CP and 3200 kcal ME/kg in the second experiment, were supplemented with six lysine levels (0, 0.06, 0.12, 0.18, 0.24 and 0.30%). Considering the traits as weight gain, feed: gain, the dietary requirement estimates for the phase from 1 to 21 days were 1.191% and 1.198% total lysine for males and females Ross and 1.174% and 1.188% of total lysine for males and females Hubbard, respectively. For the period from 15 to 40 days, considering the weight gain, feed:gain ratio, carcass yield, breast with bone yield, breast meat yield and fat pad, the dietary total lysine level of 1.125% was considered adequate for both sexes from the two trade marks.

Níveis de lisina para frangos de corte de 22 a 40 e 42 a 48 dias de idade

Foram realizados dois experimentos para determinar a exigencia nutricional de lisina total para frangos de corte Hubbard e Ross de ambos os sexos, no periodo de 22 a 40 e de 42 a 48 dias de idade. Foram avaliados ganho de peso, consumo de racao, conversao alimentary e rendimento de peito com osso e carne de peito. Para cada fase, o delineamento experimental utilizado foi o de blocos casualizados, em esquema fatorial 2 x 2 x 6, constituidos de dois sexos, duas marcas e seis niveis dieteticos de lisina, com quatro repeticoes e um total de 1920 aves. Dietas basais com 0,80% de lisina, 19,8% PB e 3100 kcal EM/kg, no primeiro experimento, e 0,75% de lisina, 18,5% PB e 3200 kcal EM/kg, no segundo experimento, foram suplementadas com seis niveis de lisina (0; 0,06; 0,12; 0,18; 0,24; e 0,30%). Considerando-se ganho de peso, conversao alimentar, rendimentos de peito com osso e carne de peito dos frangos, as estimativas das exigencias dieteticas de lisina total na fase de 22 a 40 dias foram 0,80% para femeas Ross, 0,993% para femeas Hubbard, 0,998% para machos Hubbard e 1,03% para machos Ross, respectivamente. Para a fase de 42 a 48 dias, recomenda-se o nivel de 0,90% de lisina total na racao para ambos os sexos das duas marcas comerciais.

Exigência nutricional de lisina digestível para frangos de corte

O objetivo deste trabalho foi determinar, mediante ensaio de digestibilidade, as exigencias nutricionais de lisina digestivel verdadeira para frangos de corte nas quatro fases de crescimento. Quatro experimentos de desempenho, realizados previamente, permitiram estimar a exigencia de lisina total para frangos de corte nas fases de 1 a 21, 15 a 40, 22 a 40 e 42 a 48 dias de idade. Foram utilizados 30 galos, adultos, Leghorn, cecectomizados com peso medio de 2316±190 g, sendo alojados, individualmente, em gaiolas com bandejas coletoras de excretas, utilizando-se o metodo de alimentacao forcada. O delineamento experimental foi inteiramente casualizado, com cinco tratamentos (quatro com dietas e um em jejum) e seis repeticoes. Foram utilizadas as dietas basais das quatro fases de crescimento, contendo 1,0; 0,825; 0,80; e 0,75% de lisina total. Com base nos coeficientes de digestibilidade determinados de 93,3; 93,58; 89,76; e 92,25% e considerando a L-lisina HCL suplementada como 100% digestivel, as exigencias de lisina digestivel verdadeira foram 1,130; 1,075; 0,95; e 0,84% para as fases de 1 a 21, 15 a 40, 22 a 40 e 42 a 48 dias de idade, respectivamente. Ao aplicar o modelo de regressao linear, foram obtidas as equacoes (% lisina/Mcal) = 0,4335 - 0,003284X r2 0,98 e (% lisina/Mcal) = 0,41081 - 0,003213X, r2 0,96 para lisina total e digestivel, respectivamente, sendo x a idade media das aves, em dias.

Exigências de metionina + cistina para frangos de corte machos de 1 a 21 e de 22 a 42 dias de idade, em clima tropical

Two experiments were conducted to determine the nutritional requirements of total methionine + cystine for Ross male broilers from 1 to 21 and 22 to 42 days old on tropical climate. The following parameters were evaluated: feed intake, weight gain, feed:gain ratio and absolute weights and yields of carcass, noble cuts (chest, thighs and drumsticks) and abdominal fat. The experiment was analyzed as a complete randomized design with six levels of methionine + cystine and four replicates of 12 animals, in a total of 288 birds for each experiment. The diets were formulated to meet the bird nutricional requirements, except for methionine + cystine levels. The diets were supplemented with DL-methionine at levels of 0, 0.08, 0.16, 0.24, 0.32, and 0.40%, resulting in experimental diets with 0.69, 0.77, 0.85, 0.93, 1.01 and 1.09% of methionine + cystine, for the period from 1 to 21 daysold and 0.61, 0.69, 0.77, 0.85, 0.93, and 1.01% of methionine + cystine, for the period from 22 to 42 days old. Quadratic effects of methionine + cystine levels on weight gain and feed:gain ratio, from 1 to 21 days old, and on feed intake, weight gain, feed:gain ratio, absolute weights of carcass and chest and yields of carcass, thighs and drumsticks, from 22 to 42 days old , were observed. According to the performance data, the nutritional requirements of methionine + cystine for male Ross broilers were estimated in 0.96 and 0.89% from 1 to 21 and 22 to 42 days old, respectively.

Exigências de metionina + cistina para frangos de corte fêmeas de 1 a 21 e de 22 a 42 dias de idade criados em região de clima tropical

Two trials were conducted to determine the requirement of methionine + cistyne for Ross female broilers from 1 to 21 and 22 to 42 days old on tropical climate region. The following parameters were evaluated: feed intake, weight gain, feed: gain ratio, absolute weights and yields of noble cuts (breast, thighs and drumsticks) and abdominal fat. The experiment was analyzed as a complete randomized design with six levels of methionine + cystineand four replicates of 12 birds per replicate, in a total of 288 birds for each experiment. The diets were formulated to meet the bird nutricional requirements, except for methionine + cystine levels. The diets were supplemented with DL-methionine at levels of 0, 0.08, 0.16, 0.24, 0.32, and 0.40% to contain 0.69, 0.77, 0.85, 0.93, 1.01, and 1.09% of methionine + cystine, for the period from 1 to 21 days and 0.61; 0.69; 0.77; 0.85; 0.93 and 1,01% of methionine + cystine, for the period from 22 to 42 days old. Quadractic effect of levels of methionine + cistyne on weight gain and feed: gain ratio, from 1 to 21 days old, and linear effect on weight gain, feed: gain ratio, absolute weights of abdominal fat, carcass, breast, thighs, and drumsticks and yields of carcass and abdominal fat, from 22 to 42 days old, were observed. According to the performance data, the nutritional requirements of methionine + cystine for female Ross broilers were estimated in 0.96%, for the periods from 1 to 21 and 22 to 42 days old.