142 Mineral requirements of fed cattle

The purpose of this presentation is to summarize state of the art data related to our understanding of feedlot cattle mineral requirements. To date, mineral requirements of cattle have been estimated based on historical research, some conducted as early as the 1930s and 40s. In comparison to earlier editions of the beef cattle nutritional requirements, relatively few alterations in mineral feeding recommendations were noted in NASEM (2016). However, consultants working in the industry commonly report feeding minerals far in excess of the NASEM (2016) recommendations. In addition, an abundance of mineral supplementation strategies has contributed to misunderstandings associated with cattle mineral requirements. Trace minerals, in particular, are available in a variety of chemical forms that affect site of solubility, potential bioavailability and may allow supplementation via various routes (dietary, injection, bolus, oral drench). Published and unpublished data comparing national vs. industry recommendations of trace minerals on beef cattle performance and data pertaining to source comparisons in fed cattle will be presented.