preciptin tests
The Precipitin test distinguishes between human and animal blood.
No. Only humans have human blood.
human are also animals.
It depends on what kind of animal it is. If it is an amphibian, the red blood cells will have a nucleus. Human red blood cells do not have nuclei.
human
they drink animal blood alternative to human blood
No. In fact, you would get very sick. Human blood and animal blood are different. And it's bad the other way, too: if you injected human blood into an animal's bloodstream, the animal would get very sick.
human
All vampire bats feed on both human and animal blood, but they rarely feed on humans.
chromosome 9
yes, but the blood isn't as filling as human blood.
Mainly only human blood, I can't see a vampire draining the blood of an animal.