  It takes a mallard duck 28-30 days for the eggs to hatch. All of the eggs will hatch within 24 hours and they will then head for water.Never to return to the nest. 3 people found this useful. It takes a mallard duck 28-30 days for the eggs to hatch. All of the eggs will hatch within 24 hours and they will then head for water. Never to return to the nest. 3 people found this useful.
The two main causes of strokes are termed ischemic and hemorrhagic and involve blood vessels in the brain. Ischemic strokes comprise about 80% to 85% of all strokes. With an ischemic stroke, a blood vessel in the brain becomes clogged with a clot just like the clogged arteries in the heart. With a hemorrhagic stroke, a blood vessel in the brain actually bursts or leaks. Hemorrhagic strokes tend to be more serious.
Causes. A stroke occurs when the blood supply to your brain is interrupted or reduced. This deprives your brain of oxygen and nutrients, which can cause your brain cells to die. A stroke may be caused by a blocked artery (ischemic stroke) or the leaking or bursting of a blood vessel (hemorrhagic stroke). Thrombotic stroke. 2  A thrombotic stroke occurs when a blood clot (thrombus) forms in one of the arteries that supply blood to your brain. 3  A clot may be caused by fatty deposits (plaque) that build up in arteries and cause reduced blood flow (atherosclerosis) or other artery conditions. 4  Embolic stroke.