Níveis de cálcio e relação cálcio/fósforo em rações para poedeiras leves de 24 a 40 semanas de idade

• Autor(a) principal: Vellasco, Cássia Rampini
• Data de Publicação: 2010
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5688
• topic: Cálcio; Fósforo; Minerais; Poedeiras leves; Calcium; Phosphorus; Minerals; Laying hens; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL::EXIGENCIAS NUTRICIONAIS DOS ANIMAIS

This experiment was conducted in the Poultry Department of Animal Science, Federal University of Viçosa, aiming to determine the nutritional requirement for calcium and better calcium / phosphorus ratio in the diet of laying hens from 24 to 40 weeks of age. 324 birds were used Hy-Line W-36, distributed in a completely randomized design in a 3x3 factorial scheme, consisting of three levels of calcium (3.9, 4.2, and 4.5%) and three calcium: phosphorus ratio (9 , 3, and 10.53 12,12:1) totaling 9 treatments, six replicates and six birds each. With the exception of calcium and phosphorus in the diet, which were obtained by supplementation of limestone (50% thinner and 50% thicker) and dicalcium phosphate, the other nutrients met the recommendations by Rostagno et al. (2005). We evaluated the performance (production, egg weight and mass, weight gain, feed intake, feed conversion per dozen eggs and per egg mass), egg quality (yolk, albumen, shell, shell thickness, specific gravity , ash, calcium and phosphorus in the egg shell and lost), bone characteristics (weight, ash, calcium and phosphorus in the tibia), balance of calcium and phosphorus (mineral matter, calcium and phosphorus excretion, calcium intake, consumption of phosphorus, calcium and phosphorus retained by birds) and mortality. There was no interaction (P> 0.05) between calcium levels and ratios of calcium / phosphorus ratio for the variables studied, but levels of calcium promoted effect (P <0.05) on weight and shell percentage, calcium bark, lost eggs, consumption of calcium and phosphorus, calcium and phosphorus excretion, calcium and phosphorus retained. The calcium / phosphorus significantly (P <0.05) feed intake, weight gain, feed conversion per dozen eggs and egg mass, intake of calcium and phosphorus, phosphorus excretion and phosphorus retained. For the other variables was not significant effect neither for nor calcium levels to calcium / phosphorus ratio. Diets containing 4.5% calcium and the calcium: phosphorus 12,12:1, corresponding to a calcium intake of 3.71 g / hen / day and phosphorus of 306 mg / bird / day, guarantee satisfactory performance in diets for laying hens from 24 to 40 weeks.