WINTER BONUS MAGAZINE 2026

Dietary balance: • Avoid diets with a potassium content exceeding 5% (average content of total diet on DM basis), especially for cows intended for UHT milk production. Nutritional management: • Address potential nutritional imbalances caused by high potassium, such as reduced calcium and magnesium availability, which are critical for milk stability. • Contact your local De Heus technical advisor to check your pasture mineral levels in your current ration. Genetics and breeding: • Investigate genetic factors that influence protein stability and consider these traits in breeding programmes. • Breeding focus: Prioritise κ -casein B allele, higher casein %, improved mineral balance traits, and functional protein traits to enhance long-term milk protein stability. In addition, technical tools can assist producers in identifying potential risks before milk instability becomes a problem. Using platforms like LaboExpert, pasture and other roughage mineral analyses can be evaluated by De Heus technical advisors to identify imbalances such as excessive potassium levels. Combined with FeedExpert ration formulation, these insights allow for adjustments to dietary mineral balance and overall ration composition. This approach enables proactive nutritional management, helping producers correct imbalances early and reduce the risk of unstable milk. Conclusion Milk flocculation and alcohol instability arise when milk protein stability is compromised by shifts in pH, mineral balance, diet, and environmental stress. Lower pH and high dietary potassium often linked to potassium-rich soils and pastures disturb calcium, magnesium, and phosphorus equilibrium, weakening casein micelles and increasing the risk of unstable non-acid milk, particularly during UHT processing. Acid-base imbalances, sudden dietary changes, and heat stress further heighten this risk. Effective control of pasture potassium levels, careful nutritional management, mineral supplementation, and provision of shade during heat stress are therefore essential to maintain milk stability in pasture- based dairy systems. Contact your local De Heus technical advisor to learn more about how we can help prevent milk instability on the farm – https:// www.deheus.co.za/meet-our-team/. www.deheus.co.za | 031 785 1575 | infosa@deheus.com Winter 2026 BONUS www.agribonus.co.za 16