Examining in vitro and in vivo characteristics of Intellibond and sulfate forms of copper, zinc, and manganese

Abstract

Trace minerals have long been identified as essential components in the diets of domestic livestock species. The mechanisms underlying Cu, Zn, and Mn absorption are complex, but research has demonstrated interesting opportunities to optimize the involvement of trace minerals in ruminant nutrition. To further our understanding of absorption and retention of modern forms of trace minerals 4 experiments were conducted to examine in vitro and in vivo characteristics of Intellibond (IB) and sulfate forms of copper (Cu), zinc (Zn), and manganese (Mn). In experiment 1, in vitro incubations were used to examine the effects of pH and mineral concentration and source (IB vs sulfate) on Cu, Zn, and Mn solubility. Solubility was measured at elemental concentrations ranging from 0.1 to 10.0 mg of product/ml (0.1, 1.0, and 10.0 mg/ml) at: 1) pH 5.5 (in McDougal's artificial saliva mixture 0.1 M NaHCO3-Na2HPO4KCl- MgSO4*7H2O-urea buffer) and 2) pH 2.0 (in McDougal's artificial saliva mixture 0.1 M NaHCO3-Na2HPO4KCl- MgSO4*7H2O-urea buffer). On average, the overall solubility of Cu, Zn, and Mn, from both trace mineral sources were similar at a pH 5.0 and 2.0. In Experiment 2 eight cross-bred steers were utilized to estimate the duodenal appearance of Cu, Zn, and Mn in steers post ruminal administration of IB and sulfate forms of Cu, Zn, and Mn in steers fed a corn silage and steam flaked corn-based diet. Treatments consisted of 1) 60 mg of Zn/kg DM from ZnSO4; 20 mg of Cu/kg DM from CuSO4; 40 mg of Mn/kg DM from MnSO4, and 2) 60 mg of Zn/kg DM from tetra-basic ZnCl; 20 mg of Cu/kg DM from tri-basic CuCl; 40 mg of Mn/kg DM from tri-basic MnCl. Individual trace mineral treatments were thoroughly mixed with 0.23 kg of ground corn and administered as a single dose via the rumen fistula. Rumen and duodenal samples were obtained at -4, -2, 0 h, pre dosing and at 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, and 42 h post dosing. Duodenal appearance of Cu, Mn, and Zn post ruminal administration of different trace mineral sources were similar across treatments. In experiment 3, eight cross-bred steers were utilized in a 19 d experiment to investigate the effects of trace mineral source on apparent absorption and retention of Cu, Zn, and Mn in steers fed a corn silage and steam flaked corn-based diet. Steers were blocked by BW and randomly assigned to one of the 2 treatments. Treatments consisted of: 1) 30 mg of Zn/kg DM from ZnSO4; 10 mg of Cu/kg DM from CuSO4; 20 mg of Mn/kg DM from MnSO4; and 2) 30 mg of Zn/kg DM from tetra-basic ZnCl; 10 mg of Cu/kg DM from tri-basic CuCl; 20 mg of Mn/kg DM from tri-basic MnCl. Total fecal and urine output was measured daily for all steers during the 5 d collection period. Dry matter disappearance, apparent absorption, and apparent retention of Cu, Zn, and Mn were similar across treatments. In experiment 4, four-hundred cross-bred steers (initial BW 335 ± 9.6 kg) were utilized to investigate the effects of supplemental Zn, Cu, and Mn concentration and source on performance and carcass characteristics of feedlot steers fed a high concentrate steam flaked corn-based finishing diet for 159 d and zilpaterol hydrochloride for the last 21 d prior to slaughter. Treatments consisted of: sulfate) 90 mg of Zn/kg DM from ZnSO4; 17.5 mg of Cu/kg DM from CuSO4; 48 mg of Mn/kg DM from MnSO4; IB-1) 30 mg of Zn/kg DM from Zn Hydroxychloride; 10 mg of Cu/kg DM from basic Cu chloride ; 20 mg of Mn/kg DM from Mn Hydroxychloride; IB-2) 45 mg of Zn/kg DM from Hydroxychloride; 12.5 mg of Cu/kg DM basic Cu chloride; 29.5 mg of Mn/kg DM from Mn Hydroxychloride; IB-3) 60 mg of Zn/kg DM from Zn Hydroxychloride; 15 mg of Cu/kg DM from basic Cu chloride; 39 mg of Mn/kg DM from Mn Hydroxychloride ; and IB-4) 90 mg of Zn/kg DM from Zn Hydroxychloride; 17.5 mg of Cu/kg DM from basic Cu chloride; 48 mg of Mn/kg DM from Mn Hydroxychloride. No differences were observed for final body weight (P > 0.42). Overall ADG, DMI, and feed efficiency were similar across treatments. Hot carcass weight, dressing percentage, yield grade, LMA, adjusted fat thickness, KPH, and marbling score were similar across treatments. Concentrations of Zn, Cu, and Mn in liver and blood samples collected on d 112 and at harvest were similar across treatments. Overall data collected from these 4 experiments indicate that under the conditions of these experiments, supplemental Zn, Cu, and Mn concentration and source had no impact on any of the response variables measured.