The Impact of Trace Mineral Source, Water Quality, and Short-Term Choline Supplementation on Performance and Carcass Characteristics of Finishing Steers

Abstract

ABSTRACT A total of 288 yearling steers (315.2 ± 3.7 kg) were used to determine the effects of trace mineral source, water quality, and short-term choline supplementation on feedlot performance and carcass characteristics. Trace mineral treatments consisted of 1) a control, namely, 15 mg Cu/kg DM, 20 mg Mn/kg DM, and 45 mg Zn/kg DM supplemental trace minerals in inorganic form; and 2) organic (proteinate form) iso-concentrations to the inorganic trace minerals composed of 50% organic and 50% inorganic trace minerals. Water treatments consisted of 1) a blend of reverse-osmosis (RO) water and well water (1,072.4 mg sulfate/L) and 2) well water (2,377.5 mg sulfate/L). At 29 d before slaughter, 4 pens of steers per trace mineral × water treatment combination were supplemented with choline at a rate of 20 g of rumen-protected choline/steer daily, and the remaining 4 pens served as the controls (no supplemental rumenprotected choline). There were no effects of trace mineral source, water quality, or interactions with feeding period for BW, ADG, DMI, or G:F. Initial and final BW, ADG, DMI, and G:F were similar across trace mineral and water treatments. Choline supplementation for only the last 29 d on feed did not affect performance. Morbidity, mortality, and percentage of retreated cattle were similar across trace mineral and water treatments. There was a trace mineral × water quality interaction (P