How much calcium to give laying hens

Adult laying hens (over 18 weeks of age) require 4 to 5 grams of calcium per day, but also need to provide enough other elements for eggshell formation. These include phosphorus, zinc, magnesium, manganese, vitamin D3. A “soft egg” is not necessarily a result of calcium deficiency. 

Vitamin D3 deficiency often leads to defects in egg shells and causes lameness, chickens walk little and mostly sit. A severe deficiency of this vitamin can even lead to death. Thus, without eliminating this problem, additional calcium will not correct the situation. Fat-soluble vitamin D3 for chickens is available as a separate supplement or can be added to codoil feed at the rate of 65 ml per 5 kg of live weight. 

If regular laying hen feed contains 4% calcium, then a laying hen eating 120 g of feed per day receives 4.8 g of calcium. She may need up to 5 grams of calcium or more per day during the laying season. In this case, you need to provide the oyster crumbs in a separate bowl - in the evening the hen can treat herself to as much as she needs to form a shell foregg the next day.< /span>

Good quality commercial layer feed is the simplest feeding option as it contains a vitamin and mineral mixture plus limestoneFLOUR (calcium carbonate) in required quantity to maintain eggshell production.

However, when preparing homemade diets, the balance of the main ingredients is difficult to maintain. Thus, in chicken feed, the balance of calcium and phosphorus is especially important. If you feed extra calcium without extra phosphorus, the ratio becomes unbalanced and shell quality deteriorates. Poultry owners begin to mix even more calcium into the feed, exacerbating the problem. 

What to remember is not to give extra calcium to hens before 18 weeks of age to avoid toxicity, and not to mix oyster shell or limestone grits into basic bird feed, especially commercial layer feeds. 

Do not feed dolomitic limestone. Dolomite contains 10% magnesium, which competes with calcium for absorption sites and leads to calcium deficiency, rickets and deterioration of eggshell strength. The recommended level of calcium for birds under 18 weeks of age is 1% or less, and layer feed contains four times this amount. 

Excess calcium is harmful, as is too little. High-yielding modern laying hen hybrids are more dependent on a proper calcium supply program than conventional breeds.