A. Dead animals will smell until they are completely decomposed or until they are dried out, whichever comes first. It goes without saying that the larger the animal, the more biomass there is to rot, the stronger the smell will be, and the longer the smell will last.
When cells are damaged by disease or injury, large amounts of these leak out, causing blood tests to show that enzymes are elevated above normal. (You can roughly compare this situation to a car that's leaking oil. Leaks in many parts of the engine can have the same result: oil all over your driveway.)
Test: CPK, Creatine Phosphokinase (CK) Creatine Kinase. This is a blood chemistry test to measure the amount of enzyme in the blood. The CPK enzyme is found in high concentration in heart and skeletal muscle; low concentration is brain tissue. CPK is an enzyme that catalyzes the creatine-creatinine metabolic pathway in muscle cells and brain tissue.