Christians believe the wine they drink during Mass is literally the blood of Jesus. There is no difference.
A Gentile who slaughters an animal or pours a libation for an idol is liable for a capital sin.
There are differences. Not all denominations teach this. But most in different grades.
The most strong believe is with the Catholics. There you have a priest, that does some kind of ritual, that changes the wine into literally blood.
Lutherians believe this to a certain extent too. Luther called it bloodwine. This means at least partitially real blood. On the other side are the followers of Zwingli and Calvin. Zwingli said the consumed wine is only Symbol for the assembly, Calvin tought there is no blood at all althrough a spiritual connection with the wine.
Imo honestly there is no blood at all in this ritual. Everybody can see it is only wine. Superstition.