Deficiency in which mineral may cause bone abnormalities in young, rapidly growing animals?

• A. Phosphorus
• B. Calcium
• C. Magnesium
• D. Vitamin D

Answer: (B)

Calcium is the mineral most directly needed to harden bone. In young animals that are growing rapidly, bones are forming and mineralizing at a high rate, so the demand for calcium is especially high. When calcium is deficient, the bone matrix doesn’t mineralize properly, leading to soft, deformed bones and signs similar to rickets. Vitamin D can influence this outcome by affecting calcium absorption, but the deficiency itself is about calcium availability. Phosphorus and magnesium are also important for bone, but their deficiencies don’t cause this condition as directly or predictably as calcium does. And vitamin D isn’t a mineral, so it isn’t the mineral deficiency described.