Trace organic minerals as a replacement of inorganic sources for layers: effects on productivity and mineral excretion.

The aim of the recent study was to evaluate the effectiveness of a complete replacement of the inorganic form of minerals (Cu, Zn, Mg and Fe) supplemented to layers feed with an organic form (Bioplex, Alltech Inc.) at lower inclusion level. The trial was performed on Hy-Line laying hens placed in individual cages. Birds were on trial from week 30 to 70. Birds were assigned to four dietary treatments; each treatment consisting of 48 hens in 6 repetitions of 8 animals. Groups were given feeds supplemented with inorganic or organic form of minerals in the following concentration: Control (15ppm Cu, 60ppm Zn, Mn and Fe (all inorganic sources)): 8, 17 and 33 % of inorganic concentration as organics. Performance, bone strength and mineral excretion were measured and statistically analyzed by ANOVA. Performance (lay and FCR) was similar in all the groups. Control layers consumed significantly (P<0.05) more feed than the group receiving 17% organics. A significant improvement was noted in bone strength (P<0.01) and a reduction of faecal concentration of minerals (P<0.05) in the organic groups compared to the control. The organic form maintained performance at a dosage 12 times lower compared to the commercial inorganic level.