Amino Acid Complexed Minerals Zn, Mn, and Cu Improve Bone and Intestinal Characteristics in Laying Pullets

The present study investigates the effect of partially supplemented trace minerals zinc (Zn), manganese (Mn), and copper (Cu) using 2 different sources: inorganic mineral (IM) or amino acid-complexed minerals (AACM), in pullet diets during 6 to 14 weeks. A total of 1120 Lohmann Brown Lite pullets were distributed into 40 experimental cages with 2 dietary treatments. Two dietary treatments were established: a IM supplemented with 70 mg kg⁻¹ Zn (as oxide), 70 mg kg⁻¹ Mn (as oxide), and 8 mg kg⁻¹ Cu (as sulfate), and a test diet (IM + AACM) providing the same total elemental concentrations of Zn, Mn, and Cu, but with 40, 40, and 2.75 mg kg⁻¹ from IM sources (oxides/sulfate) and 30, 30, and 5.25 mg kg⁻¹ from AACM, respectively. Data were compared by Student's t-test (P < 0.05). Zootechnical performance was not affected by mineral source (P > 0.05). However, AACM increased relative intestinal weight (P = 0.01) and small intestine length (P = 0.05) and decreased cecum length (P < 0.01). Tibia calcium and phosphorus contents were 8.5% and 6.9%, respectively, higher (P < 0.05) in the AACM group. Birds fed AACM diets showed enhanced tibia bone density (P < 0.01). Serum analysis showed elevated (P < 0.05) red blood cells, hemoglobin, hematocrit, white blood cells, alkaline phosphatase, albumin, creatinine, and thyroxine levels in birds supplemented with AACM. Supplementation with AACM trace minerals enhance bone, intestine, and blood measurements in laying pullets without impacting growth or organ weights.