This experiment was carried out to study the effects of feeding trace minerals as organic complex on the performance and bone characteristics for pullets in the period from 7-12 weeks old. The treatments consisted of the supplementation of trace minerals in the inorganic form (control) and organic form with inclusion of 0.4% in the diet, that corresponds to the supplement levels of 60, 80, 70, 10, 1, and 0.3 ppm of zinc, iron, manganese, copper, iodine and selenium, respectively, and the decreasing dietary levels of organic source (0.35, 0.3, 0.25, and 0.2%). A total of 648 Lohmann - LSL pullets from the 7th week old were allotted to a completely randomized design with six treatments and six replicates of 18 birds. No significant treatment effect on performance characteristics and uniformity up to the 12th week was observed. There was a linear reduction of ash porcentage in the tibia of pullets in the 12th week as the dietary organic supplement decreased. However there were no significant differences among the inorganic source (control) and the other treatments (organic source). The zinc content in the tibia as well as the weight, length and thickness of tibia and femur and metatarsus length were not affected by the treatments, in the 12th week. The trace mineral organic source showed relative comparative advantage and resulted in 0.2% reduction of the dietary supplement level of organic source with no effect on the performance and bone characteristics of pullets from 7 to12 weeks old.
bone characteristics; mineral supplement; performance; pullets
