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An experiment was conduced to evaluate the inclusion of sunflower meal (SBM) in commercial layer diets formulated on total or digestible amino acids basis. One hundred forty-four 41-week-old Lohmann LSL layers were distributed in a completely randomized experimental design in a 2 x 4 factorial arrangement with three replications of six birds each. Treatments consisted of a combination of four SBM inclusion levels SBM(0%, 4%, 8%, and 12%) and feed formulation according two amino acid recommendations (total or digestible). The experimental period was divided into five periods of fourteen days. Performance parameters (egg production, feed intake, feed conversion, egg mass) were evaluated for each period. In the last two days of each period, three eggs per replication were collected to evaluate egg quality (Haugh units, specific gravity, egg weight, eggshell thickness, and eggshell percentage). Hens fed on total amino acid recommendation presented the highest values for egg weight. Diets formulated on digestible amino acids basis showed an improvement in eggshell percentage and egg specific gravity. SBM addition in commercial layer diets did not influence performance; however, increasing SBM dietary levels SBM improved eggshell quality

An experiment was carried out to evaluate the effect of replacing corn with pearl millet in commercial layer diets, formulated according to the minimal requirements for total and digestible amino acids. Two hundred and forty Lohmann LSL laying hens with 25 weeks of age were distributed in a completely randomized experimental design according to a 2 x 5 factorial arrangement with 3 replicates of 8 birds. Feed was formulated on two amino acid basis (total or digestible) according to Rostagno et al. (2000) and there were five pearl millet inclusion levels (0%, 25%, 50%, 75%, and 100%). Performance and egg quality were evaluated during five periods of 21 days.At the end of each period, feed intake, egg production, egg weight and feed conversion were evaluated. In the last three days of each period, the following egg quality parameters were evaluated: Haugh Unit, yolk pigmentation index, egg specific weight, shell percentage and shell thickness. Digestible amino acid requirements resulted in decreased feed intake (p<0.01) and increased production costs per mass of eggs (kg) or per dozen eggs (p<0.01) compared to total amino acid requirements. There was a linear reduction in feed intake, egg production, egg weight and yolk pigmentation index with increasing inclusion levels of pearl millet. Therefore, increasing levels of replacement of corn by pearl millet affected bird performance negatively. Besides, production costs were higher with increasing pearl millet levels

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Desempenho e qualidade da casca para poedeiras recebendo Desempenho e qualidade da casca para poedeiras recebendo Desempenho e qualidade da casca para poedeiras recebendo Desempenho e qualidade da casca para poedeiras recebendo vitamina D nas rações de pré vitamina D nas rações de pré vitamina D nas rações de pré vitamina D nas rações de pré----postura e postura postura e postura postura e postura postura e postura .400 e 3.600 UI/kg -na pré-postura e 2 níveis de vitamina D -1.200 e 2.400 UI/kg -na postura), totalizando seis tratamentos com quatro repetições de oito aves cada. Iniciou-se com a ração de pré-postura às 16 semanas de idade das aves, sendo que a mesma foi fornecida até as aves atingirem 18 semanas de idade, quando, então, iniciou-se com a ração de postura. Os resultados mostraram que, tanto os parâmetros de desempenho, quanto os de qualidade da casca, não foram influenciados pelos diferentes níveis de vitamina D fornecidos na fase de pré-postura e na fase de postura.Palavras-chave: poedeiras comerciais, pré-postura, produção de ovos, qualidade da casca, vitamina D.ABSTRACT. Vitamin D levels on performance and eggshell quality of prelaying and laying hens. An experiment was conducted to evaluate vitamin D levels on performance and eggshell quality of prelaying and laying hens. One hundred and ninety two 16 week-old-hens were used. Hens were allotted in a completely randomized design in a factorial arrangement 3x2 (3 vitamin D levels -1,200; 2,400 and 3,600 IU/kg in the prelaying phase and 2 levels, 1,200 and 2,400 IU/kg, in the laying phase) in a total of six treatments and four replications of eight birds each. A prelaying diet was offered to 16 to 18 week-birds, followed by the laying diet. The results showed that overall performance and egg shell quality were not affected by vitamin D levels in the diet of prelaying and laying periods.Key words: commercial laying hens, prelaying, egg production, egg shell quality, vitamin D. Introdução Introdução Introdução IntroduçãoAs aves, no início de postura, experimentam o grande desafio de alcançar ao mesmo tempo a maturidade física e o pico de produção de ovos, sendo que o mesmo deverá ser mantido por várias semanas. Esses dois eventos fisiológicos ocorrem no momento em que o consumo de ração é relativamente baixo. Assim sendo, um aporte nutricional adequado é necessário para assegurar a longevidade da produção e de qualidade dos ovos, uma vez que a qualidade da casca é essencial para comercialização do ovo.O fornecimento de rações com maiores níveis de nutrientes, pelo menos uma semana antes do início da postura, é uma prática indicada para evitar que as aves no início da fase de produção não entrem em balanço negativo, principalmente no que se refere ao cálcio, o qual pode ocorrer no momento em que se inicia a formação da casca do ovo. Na fase de pré-postura, rações deficientes em cálcio acabam determinando a diminuição da qualidade da casca dos ovos na fase de produção. Para que o cálcio seja eficientemente utilizado pelas aves, é necessária a presença ...