Laying hens should pay attention to the content of calcium in laying feed in summer

The main factors affecting eggshell quality were calcium, phosphorus, manganese and vitamin D. First of all, attention should be paid to the calcium content in egg laying materials, which affects egg shell thickness, strength and weight, as well as ash and egg shell calcium content. Egg shell thickness, strength and weight increased in a curvilinear manner with increasing dietary calcium levels, and reached a maximum when dietary calcium levels reached 40%. Eggshell thickness, strength and weight were sensitive indexes for evaluating dietary calcium requirement of laying hens. The optimal dietary calcium level for laying hens at 20 to 40 weeks of age was 3.3% to 4.0%(daily calcium intake was 4.18 g).