When dogs are deficient in calcium, the following foods can help them quickly replenish calcium:

Milk Products: such as milk, yogurt, etc., but be aware that some dogs may be lactose intolerant.

Bones: Feed some clean bones appropriately, which can not only supplement calcium but also satisfy their desire to chew.

Meat: rich in protein and calcium.

Egg yolk: is a high-quality source of calcium.

High calcium dog food: Choose dog food specially designed for dogs with calcium deficiency.

Calcium supplements: May be used with veterinary advice.