Balanço eletrolítico e níveis de proteína bruta sobre parâmetros sangüíneos e ósseos de frangos de corte aos 21 dias de idade

Abstract

An experiment was conducted to determine the best electrolyte balance (EB) for broiler chicks from one to 21 days of age, based on blood and bone parameters. One day old chicks, male, Ross were reared on floor covered with shaving woods and fed with two corn-soybean meal based diet with 20 and 23% of crude protein (CP) combined with 0; 50; 100; 150; 200; 250; 300 and 350 mEq/kg of EB. The experiment was analised as a completely randomized design in a factorial arrangement of treatments (two CP levels and eight EB) with six replicates of 22 chicks each. It were evaluated blood levels of calcium, phosphorus and total proteins. Ash, calcium, phosphorus, potassium, sodium and magnesium in the bone were also measured at 21 days of age. The best values of EB estimated were 168 (20% CP) and 245 (23% CP) mEq/kg for blood calcium. The EB value obtained for the lowest level of blood total protein was 189 (23% CP) mEq/kg. The optimum EB obtained in the blood were the minimum points of the regression curve. The best value for calcium in the bone was 132 mEq/kg (23% CP). The dietary EB should be from 150 to 200 mEq/kg, concerning the biological responses of broiler chicks (from 1 to 21 days of age).