Effects of calcium levels and particle sizes of limestone on egg production and quality in pullets

[摘要] This experiment was conducted to evaluate the effects of calcium levels and particle sizes of limestone on egg production. Six hundred Lohman LSL laying hens were randomly assigned to 10 treatments: two particle sizes of limestone (DGM = 0.135 mm and 0.899 mm) combined with five dietary calcium levels (0.60, 0.75, 0.90, 1.05, and 1.20% Ca), supplemented with phytase (500 FTU/kg). This experiment was analyzed as a 2 x 5 factorial arrangement with five replicates, with 12 hens per experiment unit and four periods of 21 days each. During the laying period (18 to 30 weeks of age), the hens were fed the same diet containing 3.6% Ca. Both particle sizes tested and 0.60% calcium level showed good results of performance in the laying period with no effect on internal or external egg quality.

[学科分类] 兽医学

[关键词] hen;limestone;particle size;poultry nutrition    Introdução O desenvolvimento genético nos últimos anos tem alterado aspectos fisiológicos importantes nas aves de postura;havendo a necessidade de novas pesquisas para equacioná-los;pois;tendo em vista a maior demanda na eficiência produtiva;existe hoje a necessidade de se produzir frangas de reposição que possam refletir;na sua fase de produção;todo o seu potencial genético para máxima eficiência produtiva