Efeito dos níveis de cálcio da ração suplementada com fitase sobre a deposição de minerais na tíbia de frangos de corte de 22 a 42 dias

Abstract

With the aim of evaluating the effects of the levels of calcium in the ration supplemented with phytase for broiler chickens from 22 to 42 days old, on the deposition of minerals in the tibias, one experiment was conducted with 600 chickens of 22 days old (Hubbard-MPK), distributed in a completely randomized design, in 5 x 2 factorial arrangement (levels of Ca of the diet x sexes), with three repetitions of 20 birds per plot. The basal ration was balanced to meet the nutritional requirements of the birds according to NRC (1994), except for Ca, whose levels were 0.40; 0.59; 0.78; 0.97 and 1.16%, supplemented with phytase . At 42 days of age, two chickens from each treatment were slaughtered for removal of the left tibia for the subsequent analyses. The contents of ashes in the tibia from female were 35% higher than those of the males. The deposition of ashes, Ca, P, Zn, Mn and Mg were not affected (P>0.05) by the levels of calcium in the ration supplemented with phytase. In conclusion the increasing levels of calcium with phytase supplementation in the diets did not affect the deposition of minerals in the tibias of chickens from 22 to 42 days old.