Effect of micronutrient source on mineral status and performance of steers fed low- or high-sulfur diets

• Published in: Journal of animal science Vol. 94; p. 744
• Main Authors: Hartman, S J, Genther-Schroeder, O N, Hansen, S L
• Format: Journal Article
• Language: English
• Published: Champaign Oxford University Press 01.10.2016
• Subjects: Copper; Corn; Data analysis; Data processing; Diet; Impact analysis; Liver; Manganese; Micronutrients; Minerals; Nutrient deficiency; Studies; Sulfur; Trace elements; Trace minerals; Zinc
• ISSN: 0021-8812; 1525-3163
• DOI: 10.2527/jam2016-1532

The objective was to determine effects of hydroxy (HYD) or inorganic (ING) trace minerals within low- or high-S diets on mineral status and performance of beef steers. Forty-eight Angus-crossbred steers were blocked by BW (316 ± 2.8 kg) and assigned to a 2 x 2 factorial with low (0.25%; LS) and high S (0.53%; HS; additional S as CaSO4). Trace minerals (TM) were supplemented as 10 mg Cu, 30 mg Zn, and 20 mg Mn per kilogram DM from ING (sulfates) or HYD (IntelliBond; Micronutrients USA LLC, Indianapolis, IN). Growing period (GP; 84 d) diets were corn silage based and finishing period (FP; 78 d) diets were corn based with 12% hay. Steers (6/pen) were fed via GrowSafe bunks, and the experimental unit was steer (n = 12/treatment). Plasma and liver mineral concentrations were determined at trial initiation and at the end of GP and FP. Data were analyzed as a 2 x 2 factorial using SAS; initial plasma and liver mineral concentrations were covariates in analysis. High S decreased (P < 0.01) end of GP and FP liver Cu concentrations and tended (P = 0.1) to decrease plasma Cu at these times. At the end of GP, HS decreased (P = 0.04) plasma Zn concentrations and tended to decrease (P = 0.1) liver Zn concentrations. Final liver Cu concentrations were greater in ING steers than in HYD steers (P < 0.01). Liver Mn concentrations displayed S x TM effects (P = 0.05) at the end of GP and FP, where LS-HYD had greater Mn concentrations than HS-HYD, HS-ING, and LS-ING at the end of GP; however, HS-HYD final Mn concentrations tended to be greater than LS-HYD and LS-ING tended to be greater than HS-ING and LS-HYD. Growing period ADG and G:F displayed TM x S effects (P ≤ 0.06) where LS-HYD had better efficiency and gain than LS-ING and HS-ING. Overall, HS-HYD was less efficient than HS-ING (P ≥ 0.02) and LS-HYD (P = 0.06). Overall DMI, ADG, final BW, HCW, and marbling scores were not different (P = 0.12) due to treatment; however, steers consuming ING had larger REA (P = 0.02) than those fed HYD, and HS decreased (P = 0.03) back fat and yield grade compared with LS. In this study HS decreased markers of Cu and Zn status, and differential effects of ING vs. HYD minerals were noted, although all steers maintained adequate status.