Mineral supplementation is necessary to correct for deficiencies in forages consumed by livestock. Hawai?i producers have struggled with mineral issues that include imbalances between calcium, phosphorous, and magnesium, and copper, iron, molybdenum, and sulfur. Imbalances in minerals can be markedly different between islands, ranches, and even pastures due to Hawai?i�s highly variable forage environments that can change across very short distances. These imbalances have led to industry-wide depressed calving percentage, increased incidence of disease and other health issues, and reduced animal longevity, although the specific level of disparity varies greatly across the State. Most ranches in Hawai?i use commercial pre-mixed mineral products. However, these are inadequate at meeting the highly variable need for appropriate supplementation. Individual free-choice mineral supplementation has been around since the 1950s, although it has not been widely adopted. Practitioners tout its benefits, including increased performance and lower costs. This project investigates the feasibility of individual free-choice mineral supplementation in Hawai?i through two separate, year-long trials testing palatability and herd performance. Collected data will be used to build a decision support tool that will assist with the construction of location-specific mineral recommendations. First-year trial results document the relative palatability between a commercial pre-mix mineral ration and individual mineral components (Copper sulfate, Magnesium Sulfate, Monosodium Phosphate, Fish bone meal, and Trace Mineral salt) offered cafeteria-style to range cattle and are reported here. The trial was conducted in cooperation with five ranches utilizing cow/calf herds grazing different rangeland ecosystems. The cattle on trial did express preferences for the individual mineral components, contrary to popular wisdom, though the commercial mix was readily available. Preferences for the individual components varied by ranch and season of year. The combined cost of the individual mineral components was $18/cow/year cheaper than the commercial mix when fed at the recommended rate.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.