The use of alternative ingredients has been increasing in a continuing attempt to reduce production costs, along with the use of additives, such as carbohydrases, for their possible positive effects on nutrient metabolization by layers. Thus, this study aimed to evaluate the effects of different xylanases in diets with reduced metabolizable energy (ME) and the inclusion of alternative ingredients on the metabolizability of nutrients in diets for commercial laying hens, by conducting two metabolism tests. In the first trial,100 layers hens were distributed in a fully randomized 2 × 2 + 1 factorial design (two metabolizable energy reductions × two xylanases, plus one control diet). In the second assay,140 layer hens were distributed in a fully randomized 2 × 3 + 2 factor design (two xylanases× three ingredients, plus two control diets, positive and negative). It was concluded that supplementation with pantanal xylanase improved the metabolizability of nutrients in corn-based diets and soybean meal for light commercial layers, allowing for a reduction of up to 200 kcal/kg of ME in the diets. Xylanases are more effective on wheat bran enabling a decrease of 150 kcal/kg of ME in commercial laying diets without affecting nutrient metabolizability. The action of pantanal xylanase in diets containing fibrous ingredients was similar to that of commercial xylanase.

Objetivou-se verificar o efeito do tratamento dos dejetos de poedeiras comerciais sobre o teor de matéria seca, o pH e a quantidade de amônia volatilizada. O delineamento experimental foi em blocos casualizados em esquema fatorial 4 x 5 (4 tipos de dejetos x 5 períodos) e quatro repetições. Avaliou-se: dejetos frescos (DF), DF + óxido de cálcio (500 g.m2), DF + sulfato de cálcio (40% do peso da cama) e DF + terra diatomácea (200 g.m2), nos períodos 0 (antes da aplicação) e aos 4, 8, 12 e 16 dias após a aplicação. Observou-se que os dejetos tratados com óxido e sulfato de Cálcio apresentaram maiores teores de matéria seca em comparação ao controle. Verificou-se comportamento quadrático para o teor de matéria seca em função do período. O pH dos dejetos frescos e dejetos tratados com terra diatomácea não alterou durante os períodos analisados, no entanto, os dejetos tratados com óxido e sulfato de cálcio apresentaram comportamento quadrático ao longo dos 16 dias de avaliação para essa variável. Para a amônia volatilizada, os dejetos submetidos a aplicação de sulfato de cálcio e terra diatomácea não diferiram do controle até 12 dias após a aplicação. Contudo, a adição de óxido de cálcio nos dejetos promoveu efeito quadrático para essa variável durante todo período experimental. A adição de sulfato de cálcio aos dejetos de poedeiras reduz a umidade e o pH e inibe a volatilização da amônia por até 12 dias. Após este período recomenda-se uma nova aplicação.

The aim of this study was to evaluate the effect of dietary metabolizable energy levels on the performance and carcass yield of free-range broiler chickens from 1 to 84 days of age. A total of 900 male day-old naked neck lineage chicks were distributed in a completely randomized design between six levels of metabolizable energy (2,700; 2,800; 2,900; 3,000; 3,100 and 3,200 kcal.kg-1 diet) with six replications of 25 birds each. The increase in levels of dietary metabolizable energy resulted in a linear reduction of the feed intake, crude protein and digestible lysine intakes, as well as in the protein body deposition and protein efficiency and linear improvements in the feed conversion ratio of chickens in all experimental phases. The carcass yield, wing and abdominal fat weight and percentage of abdominal fat reduced linearly by increasing the level of dietary metabolizable energy. The diet including 2700 kcal.kg-1 of metabolizable energy in the diet of free-range broiler chickens in phases 1 to 28, 28 and 56 and 57 to 84 days of age does not interfere in the broilers performance and results in a better carcass yield in the final period of production.

This study aimed to evaluate the introduction of cassava flour, moringa leaf meal and bocaiuva pulp in laying hens’ diets on egg quality. Nine hundred eggs from Dekalb® White laying hens between 34 and 54 weeks of age rearing in semi-intensive system were used in the experiment. The laying hens were submitted to the following diets: 1 - diet control: maize and soybean meal base diet; 2 - diet with inclusion of 18% of cassava root meal+4% moringa leaf meal+4% of bocaiuva pulp; 3 - diet with the inclusion of 24% of cassava root meal+6% of moringa leaf meal+6% of bocaiuva pulp; 4 - diet with the inclusion of 30% of cassava root meal+8% of moringa leaf meal+8% bocaiuva pulp. The inclusion of higher levels of alternative ingredients intensified yolk color; it improved the percentage of albumen, yolk index, specific gravity and reduced yolk percentage. The association of 30% de cassava root meal+8% de moringa leaf meal+8% de bocaiuva pulp does not decrease the egg quality; it gives the yolk an orange yellow tone and it can be used in diets of laying hens with 34 and 54 weeks of age in semi-intensive systems.