SPRING SUMMER BONUS MAGAZINE 2026

Feature Milk produced (L) Organic minerals Chemical form Mineral salts (oxides, sulphates, carbonates, chlorides) Minerals bound to organic molecules (amino acids, proteins, peptides) Examples Zinc sulphate, copper sulphate, magnesium oxide Zinc methionine, copper proteinate, selenium yeast Bioavailability Variable; often lower depending on the source Generally higher and more consistent Rumen stability More affected by rumen interactions and antagonists Better protected from rumen antagonisms Absorption pathway Standard mineral absorption in the gut May use amino acid/peptide transport mechanisms Cost Lower cost Higher cost Effect of antagonists More susceptible (e.g., Mo–S–Cu interaction) Less affected by mineral antagonisms Typical use Basal diet mineral supply Strategic supplementation (transition, stress, high production) Advantage Economical and widely available Improved absorption and biological efficiency Limitation Lower and inconsistent utilisation Higher cost and variable product quality Table 1: Compares features of different mineral sources (inorganic vs organic) Conclusion Mineral nutrition in dairy cattle goes beyond meeting basic requirements. Interactions among minerals strongly influence their bioavailability and physiological effectiveness. Failure to account for these interactions can lead to hidden deficiencies, reduced productivity, and compromised animal health. A strategic approach that integrates mineral balance, source selection, and herd-specific conditions is essential for optimal dairy performance. Regular forage and water testing. Blood and liver mineral profiling. Consider bioavailability, not just total dietary concentration. Contact your local De Heus technical advisor to learn more about dynamics of mineral nutrition in dairy cows — https:// www.deheus.co.za/meet-our-team/. www.deheus.co.za | 031 785 1575 | infosa@deheus.com Spring/Summer 2026 BONUS www.agribonus.co.za 62