Soft Shelled Eggs Deficiency

Correct Answer: Calcium in feed

Soft-shelled or thin-shelled eggs are primarily caused by calcium deficiency in the diet. Eggshell is composed of 96% inorganic matter, of which calcium carbonate (CaCO₃) forms 94%.

Calcium Requirements in Poultry Feed (BIS 2007)

• Broiler feed: 1% calcium minimum
• Layer phase I: 3.0% calcium minimum
• Layer phase II: 3.5% calcium minimum

Eggshell Composition

• Inorganic matter: 96% (CaCO₃ 94%, MgCO₃ 1%, CaHPO₄ 1%)
• Organic matter: 4%

Layers need much more calcium than broilers because they deposit ~2 g of calcium into each eggshell. Vitamin D₃ is also critical for calcium absorption — its deficiency can also lead to soft shells.