Limestone (Calcium carbonate) is a nutritional feed supplement. Limestone is primarily used in stock feed as a calcium source. Limestone varies in composition and as such, available Calcium also varies. Calcium is the most abundant chemical in the body. About 98% of the bodies calcium is in the skeleton and teeth and represents about 2% of the animals body weight.
Animals require Calcium for teeth and bone formation, transmission of nerve impulses, muscle excitability, cardiac regulation, blood clotting and activation of enzymes.
Limestone can be included in foods and diets for beef and Dairy cattle, Poultry, Horses and Sheep.
Calcium is required by all groups of livestock, amounts are dependent to age and environment, young growing animals. A Calcium deficiency in young stock can prevent normal bone growth and retard general growth. General inclusion rates per tonne of feed vary from 5-15 kg dependent on calcium content and input from other ingredients. Calcium is supported in activity by Vitamin D as a transport agent. Calcium and Phosphorous are often grouped together in a common ratio of 2:1, however, ratios of 1:1 and 7:1 result in nearly equal performance provided the animals Phosphorous intake meets requirement.
It is vital that calcium levels are correct for the target species, calcium availability decreases when an animals intake exceeds its requirements, absorption declines regardless of calcium availability.
Limestone as a Calcium source has no withholding period, but should be stored in a dry place away from direct sunlight.