What are the dead horses in Harry potter called In fifth movie?

The dead horses in Harry Potter and the Order of the Phoenix are not specifically named. They are part of the scene where Harry, Ron, and Hermione are fleeing from the Dementors in the Department of Mysteries, and the Dementors are using the horses to block their escape.

The scene is meant to be unsettling and symbolic, representing the immense power and cruelty of the Dementors. It's also a reminder that Harry and his friends are facing serious threats and that the stakes are getting higher.