Fontes orgânicas e inorgânicas de zinco e cobre como melhoradores de desempenho em leitões desmamados

Abstract

Two experiments were conducted to evaluate organic and inorganic sources of zinc and copper and their effects on performance of piglets weaned at 21 days of age. In each experiment, it was used 90 piglets in a randomized block experimental design with five diets and six replications and three animals per plot. The diets used in experiments 1 and 2 contained 120 ppm zinc and 10 ppm copper as sulfate. The diets of experiment 1 were supplemented with 0, 300, 600 or 900 ppm of zinc in organic form or 2,400 ppm as zinc oxide (ZnO) and in the experiment 2, the diets were supplemented with 0, 50, 100 and 150 ppm copper in organic form or 240 ppm copper as sulphate (CuSO4H2O). In the experiment 1, levels of zinc from the organic source linearly affected on feed intake and weight gain from 0 to 15 days and from 0 to 21 days post weaning. Weight gain in the 0 to 35 day phase and from 0 to 42 days post-weaning and feed intake of the piglets fed diet with 900 ppm zinc from organic source were not different from the values observed on those fed diet 2,400 ppm of zinc from the inorganic form. Supplementation of diet with zinc in the organic form (900 ppm) or inorganic form (2,400 ppm) increased feed intake and weight gain of piglets in the first three weeks after weaning. Supplementation of diet with 2,400 ppm of zinc in the inorganic form reduced the occurrence of diarrhea in the first three weeks post-weaning. In experiment 2, levels of copper from organic source had a quadratic effect on feed intake of piglets in the periods from 0 to 31 and from 0 to 40 days postweaning. The supplementation of diet with copper in organic form (90 ppm) or inorganic form (240 ppm) increases feed intake and weight gain of piglets on the first 40 days post-weaning. © 2010 Sociedade Brasileira de Zootecnia.