CRIAÇÃO DE POEDEIRAS SEMIPESADAS EM GAIOLAS OU PISO NAS FASES DE RECRIA E POSTURA ALIMENTADAS COM BASE NA PROTEINA IDEAL NA FASE DE PRODUÇÃO

Abstract

Cages should ensure health, performance and well-being of the animals. The sustainability of the poultry industry in the long term depends on the relationship between performance, egg quality, welfare and profitability in these systems. This work aimed to evaluate the performance and egg quality of laying hens, caged or floor, in the rearing and laying, fed diets based on the concept of ideal protein for the production phase. In recreates, 400 pullets (Hisex Brown) were housed in two systems (cage and floor), receiving a commercial diet and managed according to the Manual of the line, between 12 and 18 weeks of age. Between 30 and 45 weeks of age, the same birds were fed diets with reduced levels of crude protein. It was used a completely randomized design in a factorial arrangement, consisting of two rearing systems (cage and floor) and four levels of crude protein (14, 15, 16 and 18%), totaling eight treatments. We used five replicates and ten birds per pen. In rebuilds were analyzed feed intake, weight gain, age at first egg and uniformity. During the laying period, was evaluated egg production, egg weight, consumption, feed conversion, weight gain and percentage of dirty eggs. Even at this stage, quality parameters of eggs (yolk weight, yolk height, albumen weight, albumen height, specific gravity, shell thickness and shell weight), blood biochemical parameters (total serum protein, plasma albumin, plasma uric acid and plasma total cholesterol) as well as length and relative weight of the small intestine, length and relative weight of the oviduct; abdominal fat and relative weight of liver, spleen, gizzard, pancreas, crest and wattles, were evaluated. The rearing system on floor is indicated for laying hens in the rearing and production, having as parameters the performance and egg quality. Diets based on ideal protein, containing 15% crude protein, are suggested for creation in floor or in conventional cages in laying stage.