It remains unbelievable to think that ruminants (such as sheep and cattle) can use grass to produce meat and milk – something that people, pigs, or poultry cannot do! However, the nutritive value of pastures in a given area can vary greatly from season to season and will not necessarily serve the daily needs of an animal. The aim of this article is to explain the importance of mineral supplementation on veld.
The missing one
Natural pastures and/or feed consists of water, energy, proteins, minerals, and vitamins. An animal needs all these nutrients to function normally. The synergistic effect of the nutrients is also of great importance, and if any one is lacking, the animal will not be able to function optimally. That is why we say that the most important nutrient is normally the one that is lacking.
Minerals are necessary for all bodily functions, including forming structural components of bones, organs, tissue, and cells, acting as electrolytes to maintain osmotic pressure, ensuring an acid-alkaline balance, and playing a role in membrane stability. Minerals also serve as a catalyst for enzymes and hormones that regulate metabolic activities. Animals need daily mineral supplementation because mineral absorption in the digestive system is highly variable. Minerals are divided into macro- and trace elements depending on the amount required by the animal.
Macro needs
Animals need macrominerals in large quantities for body structure, the regulation of fluid balance, muscle contraction, and the optimal functioning of the nervous system. Macro-elements are normally expressed as a percentage of dry material (% DM) in the supplement or ration.
Table 1 Macromineral functions and signs of a deficiency
| Mineral | Function | Shortage |
| Calcium (Ca) | Blood clotting Activation and stabilisation of enzymes Bone and tooth formation Nerve impulses, muscle contraction, and cardiac regulation | Listlessness Weak and broken bones Slow growth Decreased milk production Hypocalcaemia |
| Phosphorus (Ph) | Energy metabolism Part of DNA and RNA Cell differentiation Component of cell walls and contents Plays a role in the acid‒alkaline buffer systems of blood and bodily fluids | Poor appetite and listlessness Poor growth and weight loss Decreased milk production Poor reproductive performance Delayed immune response Bone disorders Pica |
| Potassium (K) | Maintenance of electrolyte balance Maintenance of osmotic pressure Regulation of acid‒alkaline balance Enzyme activation Nerve impulses | Decreased feed and water intake Weight loss Decreased milk production Loss of hair colour and glossiness General weakening of animals |
| Magnesium (Mg) | Enzyme activation Gives stability to structures Necessary for the nervous system, muscle function, and bone mineral formation | Decrease in feed intake Weight loss and irritability Lack of coordination with muscle contraction and tremors Foaming around the mouth and convulsions with sudden death |
| Sulphur (S) | Rumen microbe protein synthesis Important for formation and maintenance of cartilage, bone, tendons, and blood vessel structures | Decrease in feed intake Poor growth and milk production Poor feed conversion ratio |
| Sodium (Na) | Maintains osmotic pressure and regulates the acid‒alkaline balance Involved in water metabolism and the intake of nutrients | Salt cravings Poor appetite Decreased production |
| Chlorine (Cl) | Involved in protein digestion Maintains osmotic pressure and regulates the acid‒alkaline balance Involved in water metabolism and the intake of nutrients | Decreased intake Weight loss Dehydration or constipation Pica |
Small start, big win
Animals need trace elements in small quantities on a daily basis. Normally the first signs of a trace element deficiency can be seen in the health and fertility of a herd. The most important trace elements are zinc, manganese, iron, copper, iodine, cobalt, and selenium. Trace elements can be the small difference that has a huge impact on the optimal production and total profitability of a herd.
Table 2 Trace mineral functions and signs of a deficiency
| Mineral | Function | Shortage |
| Zinc (Zn) | Integrity of epithelial tissue Immune response Cell division and recovery Protein synthesis Vitamin A utilisation | Abnormal skin and hooves Bone and joint problems Delayed immune response Fertility problems |
| Manganese (Mn) | Reproduction Bone and cartilage synthesis Immune response | Poor reproductive performance Bone and joint problems Abnormal skin, hair, and hooves |
| Iron (Fe) | Oxygen transport Energy metabolism Immune response | Rare in adult livestock Poor appetite Heavy breathing Listlessness Delayed immune response |
| Copper (Cu) | Immune response Connective tissue synthesis and maintenance Reproduction Iron metabolism | Bone and joint diseases Weak hooves Early embryonic loss Retained placenta Poor hair colour |
| Iodine (I) | Energy metabolism Growth and development Immune response | Poor reproductive performance Poor foetus development Early embryonic loss Delayed immune response |
| Cobalt (Co) | Synthesis of Vitamin B12 Fibre digestion (fermentation) | Low levels of Vitamin B12 Poor body condition Poor conception |
| Selenium (Se) | Helps against oxidative stress Thyroid hormone metabolism Immune response | Reproduction problems Poor immunity |
Plan ahead to ensure profitability
Supplementary mineral nutrition is often one of the most underestimated aspects in ruminant nutrition because subclinical mineral shortages are very difficult to identify.
Mineral shortages will lead to production losses regardless of the amount of energy and protein that are provided to animals. Planning ahead for mineral supplementation on veld will ensure optimum production, which will lead to increased profitability. In this way you can ensure that any shortages on the veld will not have a negative impact on your animals.
Wil graag my Vleisbees-kudde se makro – en veral mikro-tekorte bepaal.
Bereid om die kudde vir eksperimentele analise beskikbaar te stel.