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Let’s talk about the importance of calcium How to optimise muscle function and leg & egg shell strength The rising demand in commercial layer and parent stock performance increases pressure on the birds to metabolise and mobilise more and more calcium from the intestine to the bones and uterus for eggshell production. The skeletons and dietary requirements of hens are unique relative to the level of calcium intake and the capacity of bone that is constantly being built and resorbed. in calcium requirement during eggshell formation. All the rest has to be metabolised from the bodily reserves which is a unique but delicate system. Creating and maintaining a strong skeleton by assuring the provision and availability of essential nutrients is vital to ensure a productive laying hen. Vitamin D3 is key to the maintenance of calcium homeostasis by stimulating its absorption and uptake. Deficiencies of this mineral can result in sub-optimal skeletons and eggshells.
Creating a strong skeleton
Timing is crucial for optimal laying egg performance The eggshell is formed from calcium carbonate and the layer will metabolize and transport the total weight of her skeleton several times to produce eggshells during the course of the laying cycle. The hen requires approximately 2.5 g calcium in around 20 h to produce a fully developed egg of 60 g. About 60-70% of the required calcium can be provided via the feed which is not enough to cover the peak
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The development of the structural bones occurs during the rearing phase at which the layer has nearly achieved a mature skeletal frame size. From 15 weeks to 25 weeks hens develop their ovaries and the reproductive tract which also drives the formation of medullary bone and stops the formation of structural bone. It is therefore of importance that the formation of bones is optimal before the onset of sexual maturity.
Maintaining a strong skeleton Medullary bone is a unique woven bone which functions as a calcium reserve for the eggshell formation when feed is insufficient. Medullary bone is ideally the first source mobilised when more calcium is required. As modern hybrid laying hens have been bred for high egg production and medullary
