Níveis de proteína bruta e de energia metabolizável para frangas de postura semipesadas de 1 a 18 semanas de idade

The aim of this experiment was to evaluate the performance of commercial layers between 1 and 18 weeks of age submitted to different crude protein (CP) and metabolizable energy (ME) levels. The trial was carried out at the poultry sector of the Department of Animal Science, of the Centro de Ciencias Agrarias, Universidade Federal of Paraiba, Areia-PB, Brazil. Four hundred and thirty-two Lohmann Brown chicks were used at 3 days of age according to a completely randomized design in a 3 x 3 factorial scheme, with three CP levels and three ME levels. In the first phase (1-6 wk), the birds were fed with diets containing three levels of CP: 21, 22 or 23% CP and three levels of ME: 2,900, 3,000 and 3,100 kcal/kg diet. In the second phase (7-12 wk) and in the third phases (13-18 wk), CP levels of feeding were 18, 19 or 20%, and 16, 17 or 18%, respectively, and three ME levels being 2,700, 2,800 or 2,900 kcal ME/kg diet in these two phases. It was not found interaction between CP and ME levels. Based on the results obtained one recommends for the phases from 1 to 6, 7 to 12 and 13 to 18 weeks of age the levels of 21 % of CP and 2900 kcal of ME/kg diets, 20% of CP and 2700 kcal of ME/kg diets and 16% of CP and 2700 kcal of ME/kg diets respectively

Níveis de metionina + cistina para frangos de corte nos períodos de 22 a 42 e de 43 a 49 dias de idade Levels of methionine + cystine for broilers from 22 to 42 and 43 to 49 days old

Foram conduzidos dois experimentos com o objetivo de determinar as exigências de metionina + cistina (Met + Cis) para frangos de corte machos da linhagem Ross, dos 22 a 42 e dos 43 a 49 dias de idade. Utilizaram-se, em cada experimento, 900 frangos com peso médio inicial de 0,800 kg, aos 22 dias, e de 2,540 kg, aos 43 dias de idade, distribuídos em delineamento inteiramente casualizado, com seis tratamentos, seis repetições e 25 aves por unidade experimental. Os tratamentos consistiram de seis diferentes níveis de metionina sintética (0,00; 0,04; 0,081; 0,121; 0,162 e 0,202%), correspondendo aos níveis de 0,664; 0,704; 0,744; 0,784; 0,824 e 0,864% e 0,603; 0,643; 0,683; 0,723; 0,763 e 0,803% de Met + Cis total nas dietas para as fases de 22 a 42 e de 43 a 49 dias, respectivamente. Foram avaliados consumo de ração, ganho de peso, conversão alimentar, rendimento de carcaça e dos principais cortes, sendo as exigências de met + cis estimadas por meio de modelos de regressão. Considerando-se os dados obtidos, as exigências nutricionais de met + cist total foram estimadas em 0,823%, para máximo desempenho e rendimento de peito, no período 22 a 42 dias de idade, e de 0,727%, para máximo desempenho e mínima deposição de gordura abdominal, no período de 43 a 49 dias de idade.<br>Two experiments were conducted with the objective of evaluating the methionine + cystine (Met + Cis) requirements, for Ross broilers, males, from 22 to 42 and 43 to 49 days old. Nine hundred broilers averaging initial body weight of 0.800 kg at 22 days old and 2.540 kg at 43 days old were used in each experiment and allotted to a completely randomized experimental design, with six treatments, six replicates and 25 birds for experimental unit. The treatments consisted of six different sinthetic methionine levels (0.00, 0.04, 0.081, 0.121, 0.162 and 0.202%), corresponding to the levels of 0.664, 0.704, 0.744, 0.784, 0.824 and 0.864% and 0.603, 0.643, 0.683, 0.723, 0.763 and 0.803% dietary total methionine + cystine, for the phases from 22 to 42 and from 43 to 49 days old, respectively. Feed intake, body weight gain, feed:gain ratio, carcass yield and the prime cuts yield were evaluated. The methionine + cystine requirements were estimated by regression models. Considering the performance data, the nutritional requirements of total methionine + cystine were 0.823% for high performance and breast yield values, in the period from 22 to 42 days old, and 0.727% for the high performance and low requirements of abdominal fat, in the period from 43 to 49 days old

Desempenho e qualidade dos ovos de poedeiras semipesadas alimentadas com dietas contendo óleos de soja e canola Performance and eggs quality in laying hens fed diets with soybean and canola oils

Objetivou-se analisar a influência da adição de níveis crescentes de óleo de soja e canola sobre os índices de desempenho e qualidade interna e externa dos ovos de poedeiras comerciais semipesadas da linhagem Bovans Goldline durante cinco períodos de 28 dias. Foram utilizadas 280 aves com 18 semanas de idade, em um delineamento inteiramente casualizado, com sete tratamentos em um esquema fatorial 2 × 3 + 1 (dois tipos de óleo e três níveis de óleo mais um testemunha adicional) com cinco repetições e oito aves por unidade experimental. Os níveis de óleo de soja e de canola não alteraram o consumo de ração, os pesos dos ovos, de albúmen, de gema e de casca, as porcentagens de albúmen, de gema e de casca e a gravidade específica dos ovos. Houve influência significativa da interação tipo × nível de óleo sobre a produção de ovos e a conversão por massa e por dúzia de ovos. Com o aumento do nível de óleo de soja, os resultados obtidos para estas variáveis melhoraram, entretanto, a conversão por massa de ovo piorou com o aumento dos níveis de óleo de canola. A adição de óleo de soja promoveu desempenho melhor que o obtido com óleo de canola.<br>The objective of this study was to evaluate the influence of soybean and canola oil added in crescent levels on production performance indexes and internal and external egg quality of brown commercial layers of the strain Bovans Goldline during five periods of 28 days. Two hundred and eighty hens with 18 weeks old were distributed in a completely randomized design, with seven diets in a 2 × 3 + 1 factorial arrangement (oil type and oil level, and an additional control), with 5 replicates of 8 hens per experimental unit. The soybean and canola oil levels did not affect the feed consumption; egg, albumen, yolk and shell weights; albumen, yolk and shell percentages, neither the specific gravity. There was an interaction between type and oils levels on egg production and mass conversion and per egg dozen. Better results for those characteristics were obtained as soybean oil increased. However, the egg mass conversion was negatively influenced by increase of canola oil. The addition of soybean oil promoted better performance as compared to canola oil