what does major encourage the animal to do

Old Major wants to encourage a revolution. That's why he calls all the animals together and tells him his vision of the world in which animals rule. He also teaches them the song "Beasts of England". This song become the "rallying cry" of the revolution. However, he dies before the revolution can take place. In allegorical terms, Old Major represents Karl Marx who wrote the Communist Manifesto with Friedrich Engels. That document encouraged workers to "unite against the ruling classes", just as the animals unite against the humans in the novel.